Lightspeed Attenuator - Best Preamp Ever?


The question is a bit rhetorical. No preamp is the best ever, and much depends on system context. I am starting this thread beacuase there is a lot of info on this preamp in a Music First Audio Passive...thread, an Slagle AVC Modules...thread and wanted to be sure that information on this amazing product did not get lost in those threads.

I suspect that many folks may give this preamp a try at $450, direct from Australia, so I thought it would be good for current owners and future owners to have a place to describe their experience with this preamp.

It is a passive preamp that uses light LEDs, rather than mechanical contacts, to alter resistance and thereby attenuation of the source signal. It has been extremely hot in the DIY community, since the maker of this preamp provided gernerously provided information on how to make one. The trick is that while there are few parts, getting it done right, the matching of the parts is time consuming and tricky, and to boot, most of use would solder our fingers together if we tried. At $450, don't bother. It is cased in a small chassis that is fully shielded alloy, it gets it's RF sink earth via the interconnects. Vibration doesn't come into it as there is nothing to get vibrated as it's passive, even the active led's are immune as they are gas element, no filaments. The feet I attach are soft silicon/sorbethane compound anyway just in case.

This is not audio jewelry with bling, but solidly made and there is little room (if any) for audionervosa or tweaking.

So is this the best preamp ever? It might be if you have a single source (though you could use a switch box), your source is 2v or higher, your IC from pre-amp to amp is less than 2m to keep capaitance low, your amp is 5kohm input or higher (most any tube amp), and your amp is relatively sensitive (1v input sensitivity or lower v would be just right). In other words, within a passive friendly system (you do have to give this some thought), this is the finest passive preamp I have ever heard, and I have has many ranging form resistor-based to TVCs and AVCs.

In my system, with my equipment, I think it is the best I have heard passive or active, but I lean towards prefering preamp neutrality and transparency, without loosing musicality, dynamics, or the handling of low bass and highs.

If you own one, what are your impressions versus anything you have heard?

Is it the best ever? I suspect for some it may be, and to say that for a $450 product makes it stupidgood.
pubul57
Perhaps a good way to look at this topic is as follows;

Let's assume this for starters. Let's compare three systems.
All 3 systems fit the ideal specs needed for a passive like the Lightspeed. We all agree on what sounds the most real and pleases us in terms of sound. Ya, just assume.

System #1
_________

A+B+C = music

System #2
__________

A+B+C+D = music

System #3
_________

A+B+C+D+E+F = music

Ok, since it's the total system that creates the finished sound I think it is accurate to state system 1,2 or 3 may end up sounding more like the recording was meant to.

The more simple system #1 may or may not be the most accurate system. The fact that it is more simple or has fewer parts along the way does not, by definition, mean it delivers a more accurate and pure sound. It may or may not.

System #3 has more parts along the path to the final music. It may have a power conditioner, separate tube buffer, separate autoformer, a subwoofer and on and on the options go. It may or may not be the most accurate system of all.

My point is one component (preamp) cannot, by itself, always give a more accurate TOTAL SYSTEM SOUND. Even under ideal conditions one cannot assume a passive can do this. Same can be said for an active preamp. The signal passes through too much and the speakers alone in a given system can be the point at which one type of preamp is preferred over another (delivers more accurate sound).

It is the sum of the parts. One combination of wire, resistors, caps, transformers (system) will always sound different then another. The combinations are endless with differing outcomes. Some more accurate then others. Fewer parts along the path does not always equal the most accurate. In all cases it will depend on what parts are combined in the total system.
Reminds me of my conversation with Ken Stevens when I picked of my CAT preamp and amp. Got into a conversation about capacitors and he said when looking for some, the manufacturer asked what flavor of sound he was looking for, he replied "I want the flavor of water". He decided to makes his own capacitors from scratch to pursue the least "damage" to the signal, he felt good recordings should sound good and bad recordings should sound bad - just one of many approaches to line stage design. The LSA seems to be guided by the same principle. What's best? Who knows. But it is nice to have so many choices.
This is not regarding the LSA since it is really about as "simple" as can be in terms of parts, etc. The irony about "simple" designs, with fewer parts, etc, is that it really requires some design chops to execute a great, simple circuit and I suspect it requires a master like Nelson Pass to design some great First Watt and XA.5 amps with such apparent simplicity in lack of complexity. For masters of their craft, you often see a less is more approach to design. But ultimately, my preference for simplicity may just be a personal peeve that has increased as I have gotten older. But yes, there are many ways to skin a cat to produce a world class system. What makes the hobby so much fun.
Wow isn't this fun. Nothing I'd rather be doing New Years Day after a night of no sleep and a couple Bloody Caesar's in me to take the edge off last night (or actually this morning).

Seriously though, I love it when this thread gets revised because it seems the debate just gets better each time. More people trying the LSA and of course more opinions added to the mix.

I am certain my preamp is not adding distortion or fuzz or any additional "stuff" unless my hearing is not as good as I think :-)
Grannyring

First off I'm not questioning your hearing. It took a while to understand your preferences and clearly they cannot be met through the use of a passive preamp in your system. However, since you like the debate I'm going to nitpick a bit here:).

Active preamps (and tube circuits in particular - we'll get to that in a few) in general will always be additive just for the fact they add gain to the system. Gain results in additional noise and distortion. The designer has control over limiting the effect of noise, but gain is gain no matter how you slice it. It's additive period.

Tubes by nature are microphonic (distortion), it's how they operate. I have a good friend here who designs tube circuits and he admits this. One of his favorite phrases is, "It's in the book, look it up." Microphonics equals distortion. Some tubes are more microphonic by nature than others. Take the 6SN7 for example (and the tube your preamp was originally designed around), one of my favorite tubes but one of the worst for microphonics. Some tubes are so microphonic you can clearly hear the ringing in your system. In some instances tubes (and transformers - but that is another subject) can also pick up RFI more easily. Now do tube (and their inherent) microphonics result in a pleasing sound to some. Absolutely, that's why there are so many threads on tube rolling, etc. The opposite is also true as well, you see enough threads from folks with gear whose noisy tubes are driving them nuts. The designer can again minimize the effects of microphonics in a number of ways, but there cannot be a debate on whether or not microphonics are additive, they are.

My point is one component (preamp) cannot, by itself, always give a more accurate TOTAL SYSTEM SOUND.
Grannyring

True enough, but I subscribe to the theory that less is more and specifically, less complexity in the signal path will result in more accuracy. Now system matching under those conditions is another matter. However, I think I've done a great job of it and like you think my hearing is pretty good.

For masters of their craft, you often see a less is more approach to design.
Pubul57

Just got done saying that from a system perspective, but I'm glad that someone mentioned it from a design perspective as well. The designer of a certain tube preamp under discussion takes a similar approach. In fact in a conversation I once had with him he eschewed balanced designs because inherently they are more complex and add more components into the signal path. You also often read about how some designers create circuits that minimize the wire utilized in a signal path to a matter of inches or the number of parts to a bare minimum.

However, there can be no debate that the LSA adds less to the signal than your VAC preamp if you are hearing more artifacts from the VAC. It is clearly not debatable.
Fiddler

I'm only commenting on this one because I also have VAC components and they clearly have a house sound. It's very distinguishable. IMO VAC gear creates wonderful music, but it does add artifacts and coloration and even the designer will admit it. It's also very pleasing sound and I will admit it. I have just come to prefer less artifacts and coloration from my system.

Did someone say Bloody Caesar, by golly my glass is half-empty, or is that half-full. Don't think I can take another debate today but it's getting crowded in here and I think I better get the bar tenders attention before my cup runneth out. Sorry I went on for so long. Guess I was just having too much fun.

Now back to the real fun. Roll tide...chi-ching.
Post removed 
Clio09, nice job indeed and I have a question for you and all. Seems then all the high end preamps, tube or SS, costing up to $100,000 that are not passive, just can't get it right? Or should I say as right as a passive?

Wonder why all of these manufacturers even bother? Wonder why they are considered by the "experts" as the very best.

Perhaps a passive conspiracy..just kidding.

Let's assume my active preamp is more noisy then the LSA. If it outperforms the passive in many other areas, then it may still be a preamp truer to the recording. Benefits outweigh the short comings kind of thing.

I so want a $450 passive to sound as good, or closer, to my active. I tried several passives with no luck yet. Perhaps I need a tube amp like the RM10 and some high efficiency speakers. While the Atmasphere Ma1 amps had a 100K ohm input impedance perhaps my Soundlab's just did not like the signal from that combo. It was 2D and quite thin. Very clean, quiet and detailed, but kind of white - washed. It reminded me of some Nuforce amps I once owned.

I will say the LSA had great promise when I first put it in my system. I did take notice of how much quieter it was for sure. I also noticed it was smooth and extended in the highs. I also found the bass to be pleasing. Over time the white-washed nature seemed to reveal itself on every CD I played. If I played the LSA and had to make a decision after 30 minutes it would hard to pass it up. After longer listening I became fatigued.

Something tells me my Soundlab speaker/Atmasphere amp combo just preferred an active unit. It would have been very interesting to hear the LSA on my previous Silverline Bolero speakers with the same amps.
If I can take this tube microphonics a step further for those who have tube preamps.
Try this little experiment.
Take the top off the tube preamp and turn on your system and set the volume control at your normal listening position. Then with your finger nail flick down the tops of each tube and have someone listen at the speaker for any sound comming through the drivers. This will show which tubes are microphonic. And in the case of really bad ones it will be heard out in the kitchen. And really really bad ones will feed back to the said tube and cause a runaway effect that can't be stoped.

Cheers George
Just to add to my previous post on microphonic tubes, if you hear a bonk in the speaker because of a slightly microphonic tube/s, this in turn when playing music will give and artificial effect of adding ambience/echo to the music, if that your bag so be it.
But I will always be in the camp of what goes in should be exactly what comes out, nothing added nothing subtracted, warts and all.
Cheers George
The irony about "simple" designs, with fewer parts, etc, is that it really requires some design chops to execute a great, simple circuit and I suspect it requires a master like Nelson Pass to design some great First Watt and XA.5 amps with such apparent simplicity in lack of complexity.
Or as my fellow Nutmegger Samuel Clemens once wrote:
"I'm sorry that this letter is so long, but I didn't have time to write a shorter one".

Translating this to the post I quoted, it's usually easier to fix a problem by adding a bandaid than it is to go back and rework the design to eliminate the problem.
Seems then all the high end preamps, tube or SS, costing up to $100,000 that are not passive, just can't get it right? Or should I say as right as a passive?
Grannyring

Well, I think there is a lot more to it than meets the eye. Let's just say designers have their preferences just like the audiophiles that buy their equipment. What's "right" for one may not be "right" for another. Also, designing something that makes you stick out like a sore thumb, regardless of the quality is always riskier, and in many cases less profitable. Especially when your peers are following a certain formula and marketing hype (eiher from reviewers, manufacturers, or other "experts") is telling the public what their expectations should be. This is not specific to home audio either.

Now I'm really going to throw one out there. These designers that market uber expensive amps. How would it come across from the consumer perspective if they matched it with an inexpensive little preamp? Bearing in mind that us consumers, regardless of whether it's audio components, cars, etc. have certain expectations for how $$$$$ translates into perceived quality or perhaps more accurately, status. IMO, these designers wouldn't be taken so seriously. In much the same way as if Ferrari came out and said you don't need top of the line Pirelli's on our cars, we're now going to supply generic Acme Brand tires and all will still be the same. Really?

Let's assume my active preamp is more noisy then the LSA. If it outperforms the passive in many other areas, then it may still be a preamp truer to the recording. Benefits outweigh the short comings kind of thing.
Grannyring

Again, there are specific definitions and preferences in play here, but this is precisely the point.

The truer to the recording thing aside, I'll give a personal equipment example. I've been playing around with a Transcendent Sound T-16 OTL. No one could ever confuse this amp with the term "graveyard quiet." First, there is a low noise upgrade option for it. That in and of itself should tell you something. Second, its pretty well documented that the layout of the wiring does cause some noise issues, and its slightly louder in one channel than another (and we're talking just at the speaker, not out into the listening room/position just in case anyone was wondering). The designer took some measures to rectify this as best as possible, but even he will admit the amp is not dead silent and doesn't apologize for it. In the end he replies with a simple question, "So how does it sound?" Indeed it sounds great, the benefits far outshine the shortcomings.

Ralph Karsten designs his amps to be used with an active linestages and while I've used mine with the LSA I will say it sounds better matched up with The Truth preamp I have that uses active buffers, and the Berning Micro ZOTL that is a true active preamp design. The LSA matches up much better with the Music Reference RM-10 and VAC Auricle Musicblocs.
Wow!! Out shopping and dinner and missing all the fun.

For the record,
1. I highly recommend the LSA and I plan to use it in my system ... it's all in my initial report.

2. I never said my stuff is the best. I can only report what I hear in MY system. I always emphasize "MY" system.

3. I never questioned anyone preferences ... whether tube, ss ... is the best and frankly I don't care. I buy and keep what I like.

I was simply asking for an explanation on the statement ... the signal from the source will accomplish what the recording engineer wants you to hear. It makes no sense to me since not aware of a PERFECT source or interconnect.

Pubul57 and Fiddler

Can you boys recommend the source and interconnect with consensus from all the recording engineers that will accomplish what the they want me to hear? I want to take the technology and implement it in all the cables, amplifier, speaker ... and then have a perfect system. We can nationalize if like Obama care, one size ...no, I mean one system fits all. Think of all the $$ and time we will save. Then finally all the "Best" and "King of MONO" threads are no longer dumb.

Pubul57, did you really sold your Lamm, CAT, Ferrari 458, Joule, Porsche 997, Atma-Sphere, VIVA ... for the LSA? Only seen it in 5555 threads so wasn't sure.

Bye Fiddler, Happy New Year.
Yep Clio09 your points on the high end builders are interesting. Your real life example with the Transcendent amp is a great example.

Ok, time to listen to Van the Man with my microphonic tubes:-) Van's voice seemed you ring more when he was younger. He now has a warmer, mumbling tone that is more microphonic tube friendly.

I will try George's tube test soon.
I will try George's tube test soon.
Grannyring

It's not my tube test, it's a well known way of checking for microphonic tubes out in the field among techs without the use of expensive equiptment. You can aslo do the same with tubes in poweramps, not just pre's.

Cheers George
Tube test complete - no ringing or any bad noises at all. Listened to Van and enjoyed it lots!

I have rolled quite a few 6sn7's in my active preamp over the past two years and have never had a microphonic tube issue as an fyi.

Knghifi, funny stuff.
Knghfli - no, I kept the Atma-sphere preamp, ideal match with their amps. The only reason I mention those other linestages is because there is something to be said for the context of what I am use to. Being enthusiastic for the LSA just would not be the same if I came to it from a $300 NAD preamp, of course I would be enthusiastic. But the point is the LSA is not just good for the money, but good to someone who has owned some very fine tube line stages; that does not mean that someone else will come to the same conclusion that I have regarding the LSA, and I'm sure that others might prefer the CAT, Joule, etc. and they great line stages indeed and I could easily live with any of them, but I still like trying different gear. I'm just trying to make the point that it is with line stages of that quality that the LSA should be compared with (and the Bent TAP AVC, K&K S&B TVC, Goldpoint, and the Placette which I have also owned), at least to audition it and see if it floats your boat.
Have enjoyed reading this thread from the very start, so here's my take on the Lightspeed Attenuator:

1) I and a follow group listners auditioned it in a very high end system and thought it was good but nothing earth shattering, I had shared this with Paul I believe with a voice mail or E-mail, that its sonic performance was not a significant or qualitative shift over the sonics of other great passives which I have used as references such as the Bent Tap TVC or the Placette buffered. I choose not to put the results of this auditioning experience on this thread for two reasons. I had a hunch it would be dismussed by some of the true believers in the Lightspeed because of this or that, impedence mismatch or something else, not fully broken in, which power supply, etc. Secondly, this is not Paul's position, well that's just your personnal taste anyways. Absolutely, personnal taste and system synergy is and will always be present. My system just does not offer the same illusion of real music with any passive including the Lightspeed compared with a reference tube based linestage.

2) It's the price dummy, it's the price! Yes, I totally agree with the permise that this piece offers tremendous valve for the money, even if it's no better then the above mentioned passives which I have used as references at different times in my system, it still costs thousands of dollars less! However, that does not mean, taking out the performance vs cost ratio, that it ranks as one of the world's great linestages because it stills lacks what great active tube linestages have to offer in my opinion. I have no worries regarding heat or tubes wearing out.

3) I have nothing but respect, trust, and kind feelings towards the man who started this thread, Paul, who writes extremely well and helps spread very interesting and useful information here on the GON. Happy new year Paul. However, if I did not know better, and I do, I would think that Paul is either George's private partner, owns lots of shares in George's company, or finally gets a piece of the action. Now none of this is true, please, I'm trying to make an attempt at humor and Paul, if you take what I just stated seriuosly, I apologize in advance. However, George should be very greatful, this thread at times comes across to me like an unpayed advertisement or a missionary message to Gon members to save us from ourself's regarding the slippery slope of performance vs cost ratio. I know it's a flaming bargain!, but how many times is it necessary to state this over and over again. It's makes perfact sense that George has an invested interest regarding his baby, I think him taking the time to help out on this thread with useful information regarding how to maximize your Lightspeed's performance is terrific, but please you have not invented the "sonic wheel", even though you offer a great product at a very reasonable price. I do totally accept that you have a position regarding what a linestage should offer sonicly in one's system, however your take, is no more right or wrong then my take or anyone's else's. It's personnal taste not an objective measure in the long run in this hobby. It just seems to me, and I understand why, George, is stating to come across as a salesman on this thread.

Well, that's my take on this marathon discussion, it's always fun to see what the next post will be, so I'll keep reading this thread, but I'm keeping my tube based linestage for now, even though it would be great to save so much money, but just don't like passives in my system any more, but the Lightspeed might be great for you in your system!
There is something to be said for those that have a conviction and stick by it. I have a lot of respect for what George did with the LSA because he has determined what he feels a preamp should accomplish, and while I agree that his way is no more right or wrong than anyone else, he has developed a product based on his conviction regardless of the fact he could have probably made more money developing active linestages had he chosen to go down that path.

Its like Ralph Karsten's approach and his conviction about using output transformers in amp circuits. He is in the minority among his peers (even though his research and papers do a great job explaining why his approach may be the better one), but he keeps plugging away at it when IMO it probably would have been easier for him to just design a circuit with output transformers and call it a day.

Lightspeed ahead...
Hi Clio09, I too have great respect for Ralph Karsten's designs and his passion for what makes the most sense to him sonicly and design wise.

However, I have no awareness historically that he ever "pushed" his design/product on an Audiogon thread like it seems to me that George is doing now on this one. Please I'm not referring to the information to help members understand his design or optimize its performance, but it seems to me that he really believes that his piece is the "BEST" there can be in linestage.

Your other remark that George, "proably could have made more money developing an active linestage", but chose not to because of his conviction to this design is not only pure conjuncture on your part, but kinda silly that he rather make less money then more from a business sense.His use of the LED design instead of transformers or resistors is quite interesting, but does not put him, in my opinion, in the patheon of designers like Ralph Karsten, Nelson Pass, or Masataka Tsuda.

So, I still believe that the way this piece is being "marketed" on this thread or how George comes across in his "conviction" that his linestage is the "BEST" regarding his design is quite different then anything Ralph Karsten has ever done on any Audiogon forum.
I think Terry is a very gifted listener and reviewer with exposure to some of the finest equipment in the world and have nothing but respect for his observations and conclusions about his views on equipment, but though we have owned similar equipment at different times, I think we lean towards a different kind of sound and we might not come to the same conclusions - though I have no doubt I would love his system. He might be right that part of my enthusiasm is in part what the LSA does for the $$$, though I would have no problem buying a more expensive line stage if I wanted to, but ultimately I think it is simply that the LSA works really well in my system and after quite of bit of A/B I felt it offered just as much musical pleasure as my tube linestage, which up to that point was my favorite after several years of listening to various preamps, a line stage with Terry also heard but wasn't exactly his cup of tea.

Still, I do the "best" concept really makes no sense, it makes no sense universally, independent of system context, not does it make sense to any particular listener. But it sure does make sense to try an LSA to see it how it works for you and then decide for yourself.

Ralph Karsten and Nelson Pass? You are right, they are at the very top of world class design talent, as is Roger Modjeski in my view, who also is in the passive line stage camp feeling no active line stage would better for use with his RM10 MKII and RM9 SE amps. Now, while Roger sells a $135 Pot-in-a-Box with a very high quality Noble pot, I think George has simply built a better mousetrap by avoiding a physical connection to change resistor values.

I think there is more debate about active versus passage than between the SS/tube divide in that even within the very same listener one might find ambivalence of conviction over which approach is best over time. I've made that journey several times, the allure of tubes is always there, but at least for me, the Music Reference amps have never sounded better than through the LSA.
Please I'm not referring to the information to help members understand his design or optimize its performance, but it seems to me that he really believes that his piece is the "BEST" there can be in linestage.
So, I still believe that the way this piece is being "marketed" on this thread or how George comes across in his "conviction" that his linestage is the "BEST" regarding his design is quite different then anything Ralph Karsten has ever done on any Audiogon forum.
Why shouldn't he believe its the best? That's one of the things I like about George (a bit cocky for a designer, kind of reminds me of me in fact). You don't think Ralph feels the same way about his OTL designs? He might be more politically correct (in some peoples views) about how he goes about it, but he often refers to his white papers here to back up his work. Some people consider that a marketing ploy, but I don't blame him one bit for displaying his research and expertise. There's also a little thing going on over AA where he posted a review of one of his amps. Some people have been critical of that, but I take no exception to it.

I don't see where George is forcing his product on anyone here. Does he come on a little strong sometimes with his convictions, sure, but I don't care. As a consumer I get to make choices. This thread has been going on for a while. If something were truly wrong I'd have to think the moderators would put an end to it.
Your other remark that George, "proably could have made more money developing an active linestage", but chose not to because of his conviction to this design is not only pure conjuncture on your part, but kinda silly that he rather make less money then more from a business sense.
Yep, it's conjuncture. However, I get the feeling from reading stuff and dealing with George directly that he being retired had a successful enough run in his career that at this point he'd rather be surfing than working any harder than he chooses to. It's a hobby and something fun for him to do. I can appreciate someone who can make these types of lifestyle decisions when others are slaves to their work.
His use of the LED design instead of transformers or resistors is quite interesting, but does not put him, in my opinion, in the patheon of designers like Ralph Karsten, Nelson Pass, or Masataka Tsuda.
I think Nelson Pass paid George one of the highest compliments when he went public on the DIYAudio thread with his own variation of George's LDR design. Enough said.

I know two of the three designers you mentioned personally and respect them enough that I use their equipment. I consider Masataka Tsuda a friend and one of the most gracious men I have ever met in my life. I'll be working with him again at the upcoming CES/THE SHOW in Las Vegas. So with that in mind I will say that design principles and preferences aside, as well as differences in personality, I think George and Masa are more similar than they are different. Both use some very unique concepts in their designs that should be heard by more people.
Very well said Teajay. Thanks to Paul/Pubul for stimulating people. He has an interesting perspective as someone who owns both the LSA and an active tubed pre-amp due to system requirements. That dialectic would bother me at the end of the day, but he seems to straddle the divide admirably.

George made some interesting statements about tubes and tube distortion. I love Jazz, and a lot of my favorite recordings were done in the 50s. If I am not mistaken, that means tubed mics, tubed microphone pre-amps, and tubed consoles, etc. Paul Weitzel has done a lot of recording for Sony, FIM, Fidelis and others. He produced some of the first SACD offerings and is a Grammy voter. Paul still uses tubed mics with their own regulated power supplies, tubed microphone pre-amps through a Neve console (which is known for having a warm midrange and uber gain). His recordings are some of the best I have heard. Distortion is not the first word that comes to mind.

While playing with the lightspeed and a direct drive scenario (source driving amps), I did appreciate the apparent clarity and speed. On the other hand, I noted compression of the sound stage, particularly depth, that all important third dimension. If that depth is a tube or gain-based artifact, I like it. It mimics the real thing which should be our frame of reference.
Well, tubes definitely do "something" I like, my amps are loaded with them and even the great First Watt and XA.5 designs by Nelson Pass were not enough to convince me to keep them and replace any of my amps, though I very much wanted to get rid of the maintenance issues with tubes, but at the end of the day, for whatever reason, I prefer tube amps - distortion or not. In fact, I'm not sure I would be so keen on the LSA if used with an SS amp as I would hear the amp more clearly, and I think an SS amp needs a tube line stage to sound the way I would like it. I have been focusing on the sound stage through the LSA, as Terry did write to me about the listening sessions he refers to any he reported the same issue with the group feeling the LSA was missing some of the sound staging capabilities of the actives. No way am I going to question that is what the group heard, these are seasoned and unbiased folks as far as I know. After Terry's note I really looked for that up against the Joule which is particularly well regarded for its sound staging abilities and I honestly did not find that flattening, but that was on my systems with my amps and might not be so with other systems. Why you really have to audition and decide for yourself if it works for you - as you would with any piece of equipment and with a few grains of salt in concluding about any piece of equipment simply based on the honest opinions of others.
Hi Paul, thanks for your kind words towards me. As to be expected from you, words of wisdom:

1) Everybody finally has to audition for themselves to really know what works for them.

2) That unless you use tube power amps the Lightspeed might lack depth in the soundstage and what I call image density or air around individual players. Also tubes still offer, regardless were you have them in the chain, more natural timbres and the the body of the harmonic then SS or passives in my opinion. When I heard the Lightspeed it was with SS amps not tube amps. That's why I believe Paul gets such great performance out of this passive because he does use tube based amps. For me in my system I like SS amps with a tube based linestage to get what I'm looking for sonicly.

To respond to another great GON gentleman, Clio09, who was nice enough to even offer sending me his Lightspeed for me to audition and we have had nice chats regarding his experience with Concert Fidelity gear and his personal relationship with Mr.Tsuda. I'm not attacking George or his product. If you find it appealing to what you refer to in George's attitude as, "a bit cocky", I personally don't like arrogance in any form by anybody. You know George personally I don't, I still think he comes across not as a designer/builder with great confidence or pride over his product as he should, but somewhat condescending towards other viewpoints other then his own.Was your own example regarding that Nelson Pass on a DIY board posted a different version of the LDR proves that George ranks with some of the great designers of the audio world? My take on this is Nelson Pass is open minded about experimenting with different designs, gives credit when credit is do, and is the antithesis of cocky or arrogance. Enough said.

Clio09,when I used the term that George was forcing his product on this thread this was refering to how he comes across to me as being somewhat of a salesman, with the position that his take on what a linestage should offer is the only objective/correct one and this thread was turning into great unpaid advertisement for his piece. Finally, I don't care what happens on AA, my comment was regarding that I have no historical awareness that Ralph or any other well known designer has ever pushed as hard to sell his product as George has, if you can remember someone please share.
I think we can all agree in that in many ways Nelson Pass is one of the greatest designers on the planet. I always wonder what he might have done if he applied his efforts towards tube amplifiers, but at he said in his manuals, there were already a lot of great tube amplifiers and making a great sounding SS amp was a bigger challenge for him, he obviously succeeded!! I also suspect that if I had different speakers, I would have kept his XA30.5, the best SS amp I have heard, but my speakers are really designed for tube amps and damping is not a particular advantage for them. Why you can really judge a system, but much harder a piece on its own, and why there never will be can never can by a "best" in any product category, and why a good dealer or a good cadre of fellow audiophiles are so helpful in building a satisfying system. And Terry, your room doesn't hurt:)
Teajay,

I haven't for a moment felt that Georgelofi was "selling". Defending? Sure, and rightly so.

In my opinion, there have been numerous manufacturers, modders, retailers, etc. that have been egregious in attempting to sell their wares here on the 'Gon, and possibly even Ralph Karsten. I have great respect for Mr. Karsten, but I have ocassionnaly thought that his responses on the 'Gon were as much about sales as defending his products.

If George's motive here was about selling, why would he have given his product away to the DIY community for free? Jump over to DIYaudio and look at the thread there. He gave his design away for free from the very beginning and he made countless posts there trying to help guys with their build. The LSA thread at DIYaudio makes this thread pale in comparison. I reiterate, why would a guy who has freely given his design away for free push hard to sell it here? It doesn't make any sense and it would be counter-productive.

I suspect, based on results, George could be selling the LSA for easily twice what he is selling it for.

Given the facts, your accusation appears hollow, in my opinion.
Please Fiddler, accusation has such a negative and bombastic tone to it. The only example I will give of someone who has given so much to the DIY community is Nelson Pass, yet he has never on any post here on Audiogon marketed his wares or ever stated his opinions as the only veiwpoint regarding performance as the absolute truth as far as I can tell, like the man that you say I'm unfairly challanging.

I just shared my opinion regarding my impression of how George comes across to me on this thread, somewhat negatively towards any design that he deems not being totally true to the source, what ever that means, and secondly this not DIYaudio, but Audiogon were threads normally are not used by designers to sell products, and if they do they are rightly called out on it.

Finally, your statement regarding George's reason for posting have nothing to do with selling because he gave it away for free to the DIY community, hum, has not Nelson Pass done the same thing, yet has never pushed his products like George has on this thread.

Sorry, if my impressions regarding George's motivation comes across as a personal attack on the man to you. I don't know George, I'm not a member of the DIY community, and I don't want to jump this fine thread with this side bar discussion regarding George. I'm sure George is a good guy who makes a very good product at a very reasonable price.
Nelson Pass indeed has given a lot to this community as is evidenced here:

Pass DIY

In fact, go to the projects section if you're inclined to see some of the ideas and schematics Nelson allows DIYers to use:

http://passdiy.com/projects.htm

If you look down the list just a few lines, you'll see an article on the B1 buffer. Nelson's version of a passive but with active JFETs for the buffer stage to control impedance matching. I like the way Nelson writes. He divides his articles up into sections analogous to LP sides. This article is no different and for those not inclined to go over there and read the article, here is an excerpt of Side A:

The First Watt B1 Buffer Preamp
Nelson Pass, June 2008
Side A

So here we are in the New Millennium, and thanks to Tom Holman and THX we’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more.

Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.

Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control.

What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.

And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!).

Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp.

I suppose if I had to floor the accelerator to drive 55 mph, maybe I’d think the life was being sucked out of my driving. Then again, maybe I like 55. Nice and safe, good gas mileage…

He goes on to talk about impedance matching/mismatching as well before getting into the technical stuff. My point simply is he talks about some of the same things those of us who prefer passives and George talk about here.

I still think Nelson paid George a nice compliment by publishing his own LDR schematic based on George's work. The two certainly share similar opinions IMO.

Fiddler's point on Goerge's IP is pretty valid. If George wanted to make quite a few bucks off this it would have been pretty easy to do. Instead he's given his IP away. No he's not the first and he won't be the last, but he still did it. Now there are people out there, both DIYers and manufacturers, building their own versions of LDR preamps (using all or parts of George's ideas) or incorporating LDR volume controls in their active preamp designs. I'd say that's another compliment to George.
Teajay, you posted, "I have no historical awareness that Ralph or any other well known designer has ever pushed as hard to sell his product as George has, if you can remember someone please share."

You didn't just "share your opinion". In your own words you flat out accused George of pushing hard to “sell his product".

And the fact that Nelson Pass has given much to the DIY community has nothing to with this discussion other than to offer some misdirection and a weak attempt to justify your accusation after you were made aware George had given his IP away.

And in your last post your accusatory tone continues by saying, "...and secondly this not DIYaudio, but Audiogon were threads normally are not used by designers to sell products, and if they do they are rightly called out on it."

If anyone is being negative and bombastic here, it is you. We can both agree that designers should be called out here for shilling their products. I'm with you on that one. But it is my opinion that your accusations against George have been grossly unfair. Considering the fact that you haven't given a single, concrete example of where George has attempted to sell his product to anyone, combined with the fact that he freely gives his design away; it appears you are left with a rather untenable position.

Teajay, I will be the first to join in with you when someone is truly shilling here (and it happens often), but I think you may simply be misinterpreting George's defense of his baby as something more nefarious, especially in light of the fact he has given it all away.
Fiddler, if you think I have been nefarious and bombastic towards George that's OK with me.

I gave him credit for sharing information on his design and for helping people who own it get the best performance possible in their systems, sounds nefarious to me so far.

Then when I gave my opinion in a respectful way that it seems to me George is a little full of himself regarding his perspective on what a linestage should offer sonicly and that for an Audiogon thread it started to seem to be somewhat of unpaid promotion forum, wow, that sounds bombastic and accusatory doesn't, then I became a SOB in your opinion.

Your weak attempt at being disingenuous towards what information I did share regarding the difference between someone like Nelson Pass who gives things away to the DIY community but does not use Audiogon threads to market his wares, does not negate your final silly statement,"that George has given it all away". Really, as far as I know he still charges money for his LDR, he does not build them and give them away for free.

Gee whiz, guys lighten up. I'm not attacking George personally, I gave his product and his pricing of it a postive comment and I'm entitled to my opinion about the other issues.

Finally, I apologize to Paul for influencing this thread away from the great discussion concerning passives vs active linestages that was very informative and interesting. I guess you have to be very careful about sharing your opinion, even though I thought I have been respectful, when it comes to certain people's friends or heros.
Teajay, I get the problem now. You aren't carefully reading the posts here .

I didn't say you were being nefarious. Re-read my post. "Nefarious" was related to George's "defense".

And you are still implying that George is marketing his wares, "difference between someone like Nelson Pass who gives things away to the DIY community but does not use Audiogon threads to market his wares..."

As I said before, you haven't given one example of George, "marketing his wares". You just keep twisting words to try to defend your position.

And when did I ever imply you were an SOB? More twisting of words.

And talk about being silly. You clearly know that when I said, "that George has given it all away", that I was talking about his IP. I even used "IP" and "design" in my posts. I think it is clear who is being disingenuous here.

"Gee whiz, guys lighten up."

Take a little of your own advice. Had you not accused George of "selling" here in the first place (once again, without one example to back the charge up) we wouldn't be having this conversation.

And BTW, George isn't a friend or hero. I've never met the man, seen the man or even talked to the man. I simply don't like to see people falsely accused without one speck of evidence being provided to back up the claim.

And I agree it is unfortunate that this thread got sidetracked from the OP's question which was offered with a lot of caveats:

"So is this the best preamp ever? It might be if you have a single source (though you could use a switch box), your source is 2v or higher, your IC from pre-amp to amp is less than 2m to keep capaitance low, your amp is 5kohm input or higher (most any tube amp), and your amp is relatively sensitive (1v input sensitivity or lower v would be just right). In other words, within a passive friendly system (you do have to give this some thought), this is the finest passive preamp I have ever heard, and I have has many ranging form resistor-based to TVCs and AVCs."
Knowing Terry as I do, I suspect it was not his intention to falsely accuse anyone, though it may have come off that way a bit, one could also feel George comes on strong in support of his product, because he does - he is a true believer, but I don't get the sense he's motivated by "making a killing".

It is also frustrating to have the "impedance mismatch" thrown out as reason why you might prefer a $$$$ line stage, but some times that is true, and some times it is just a preference for a certain kind of sound. Terry is certainly open to passives, he (and Roger Modjeski and Anthony - Clio9) is the one who took me in this direction, so I don't think he has any bias towards passives, though he had a TVC and Buffered passive which would have addressed impedance matching. He then moved on to a series of tubed linestages that he preferred, and he listens to a lot of good gear.

Now, in my system I happen to prefer the passive to the actives I have owned (I won't list them:)) - but I suspect, but don't know, that the fact I use a tube amp is one of the reasons. When it comes down to it we like what we like, and we all hear a bit differently and listen for different things. But, I still like the "theory" behind a passive that minimally alters what was recorded (even though the recording itself is an artifact of the microphones used, and the electronics used in the recording chain - that "manipulation" is at least in the recording engineers hands and part of the creative process) - none of this is live or "absolute" afterall.

On the subject of shilling, I never mind a manufacturer promoting his ideas as long as it is clear he is the manufacturer. We know where they are coming from and they are subjecting their view to public examination and comment (and criticism) - nothing is hidden. I do mind dealers for a product not identifying themselves. Relatives or friends of the designer not revealing that relationship. Or even folks that defend a product they happen to own and make claims for that product that they don't quite believe but knowing one day they will have to sell that product on AGON - wouldn't be prudent to say anything negative about the product till it is out of their hands. I am none of the above, I simply think the LSA in the right system is awfully good, and a great value.

Nelson Pass does not need to come on AGON, he has 10,000s of very satisfied customers with some of the best gear on the ever made to speak for him. He saves himself for the DIY community, as did George. My feeling is George believes in his product and is excited to see that some folks have discovered his product and like it as much as he does - hard not to find some satisfaction in that.
Ok, please don’t yell at me Fiddler. Please read George’s post below. Seems pretty clear he is saying it is the most accurate means to hearing recorded music. He implies this on his LSA vs all other attempts at a preamp. He has said this same thing in several other posts here. I have no problem with him thinking this or saying it, I just don’t agree and want to voice my opinion.

“the Lightspeed Attenuator (LSA) as you guys have nick named it, is the closest you will get to playing music that's truest to the source (cdp, phono ect), and the truest way to hear the way the recording engineers wanted you to hear how they have recorded the music.

12-31-10: Georgelofi
You are right guys the Lightspeed Attenuator (LSA) as you guys have nick named it, is the closest you will get to playing music that's truest to the source (cdp, phono ect), and the truest way to hear the way the recording engineers wanted you to hear how they have recorded the music.
As it adds nothing and subtracts nothing, like I say it is like you have plugged the (cdp or phono ect) directly into the poweramps input, no preamps at all in the signal path, yet still maintain control over the level (volume).
I accept that for some listeners it's preferable to have the added ambience, echo (if you have microphonic tubes). Also the tonal changes, because all active components have their own signature, even different brand potentiometers (Alps, Bournes, Penny&Giles ect)) sound different, compared to a direct (source to poweramp connection) gives, maybe to their ears this is preferable.
But the Lightspeed Attenuator is all about listening to the source nothing added nothing subtracted warts and all.
. . . now that that school yard bickering is finished ;) let's get back to the topic of the Lightspeed and its performance . . .

I took posession of my Lightspeed last week and have only about 5hours on it thus far. Last night I was listening to Bobby McFerrin's latest CD which is a spectacular vocal potpori of harmonies, complex arrangements and some rather interesting African tribal chants and rythmns. I got goose bumps listening to it and for the first time those goose bumps migrated down my body to my legs - wow, what a sonic affect and physical sensation.

Now considering that I am using an old Sony 5 disc carosel CD player and that my room treatments were in disaray due to some current reno's I'm doing, I would hazard to guess that these sub-optimal conditions that didn't exist when I used to use my Audio Aero Capitole MKII SE CD/Pre speak volumes to the excellent quality of the Lightspeed.

Of course you could argue that with so many different variables that it's next to impossible to isolate the sonic goose bumps to the Lightspeed alone, and of course you'd be correct. However, I'm pretty sure the Sony's sonic quality isn't as good as the Capitole so what I heard was an improvement, plain and simple.

Congrats George!

Kevin
Ok, please don’t yell at me Fiddler. Please read George’s post below. Seems pretty clear he is saying it is the most accurate means to hearing recorded music. He implies this on his LSA vs all other attempts at a preamp. He has said this same thing in several other posts here. I have no problem with him thinking this or saying it, I just don’t agree and want to voice my opinion.
Grannyring

I don't have any problem with people disagreeing or voicing their opinion as long as they are not shilling (which you are not) and are open to respectful rebuttal, as you have been. Nor do I take issue with George's strong comments regarding his design. As I said previously I like his conviction.

I don't see any examples of him selling though (and I didn't interpret your comments to indicate he is). That's kind of where I'm puzzled.
I guess we will not, nor can we. resolve the issues of what is best, and if the LSA is better than Product X, Y, or Z, and the try to deal with the issue of what "better" means and in what context. Maybe if the Subject were: Lightspeed Attenuator - Worth a Try...." we would be closer on the subject. BUt. I think we all understand that how good we think the LSA versus other great line stages will depend on the amp it is used with and other factors, and the kind of sound we like, which we are perfectly entitled to, and isn't worth arguing about, that is fruitless and can turn personal which would be ridiculous.

Perhaps the issue of active versus passive, and when one approach would be preferable is a more interesting technical subject - for example Ralph Karsten seems to often that the real issues is controlling the preamps ability to control the interconnect, and even then I think he admits it is more of an issue if you have the need to run long interconnects. On the other hand, he makes very good linestages and is never going to say you don't need an active linestage, I would not expect that of him. In fact, I think his amps do benefit from an active linestage with some gain.

These discussion are interesting for folks that love the hobby and gear. For my non-audiophile brother who just wants to listen to music, I would tell him to get the LSA/RM10 combo for less than $2,500, a speaker that can be driven by 35 watts, and feel comfortable that I gave him very good advice in building an excellent, affordable system.
Clio09

I assumed my point was clear. Sorry. Yes that was the example I gave for Fiddler on the obvious pushing of the LSA.

That's all.
For my non-audiophile brother who just wants to listen to music, I would tell him to get the LSA/RM10 combo for less than $2,500, a speaker that can be driven by 35 watts, and feel comfortable that I gave him very good advice in building an excellent, affordable system.

Without a source he isn't going to be able to listen to his system;)
Details! Details! Mac and Wyred 4 Sound DAC - he does not know what a turntable is.
I assumed my point was clear. Sorry. Yes that was the example I gave for Fiddler on the obvious pushing of the LSA.

Thanks for clarifying. We can agree to disagree on this one too:)
I don't have an issue with George attracting sale via Agon through his participation in the thread. The man is in business to make a living so however sales are generated, it's fine with me. I don't agree with some of his statements and wish he could answer some of my questions. I'm still stuck on " ... is the closest you will get to playing music that's truest to the source (cdp, phono ect), and the truest way to hear the way the recording engineers wanted you to hear how they have recorded the music.
As it adds nothing and subtracts nothing ..."

The internet is great where one can exchange ideas from anyone in the world ... no borders. Fiddler, before you get offended again, please hire a new translator that understands English.

After all the debate, I decided to play LSA last night for some serious listening. I'm finally hearing the lights so I've decided to sell my BVDs, Wilson Jack Kramer, Schwinn Varsity Sport and yes, my Calvins. Nothing ever came between my Calvin except, LSA!!!

If anyone is offended, it's the Shiraz and I'm not responsible. Boy, I like being a Democrat.
Knghifi
wish he could answer some of my questions. I'm still stuck on " ... is the closest you will get to playing music that's truest to the source (cdp, phono ect), and the truest way to hear the way the recording engineers wanted you to hear how they have recorded the music.
As it adds nothing and subtracts nothing ..." Knghifi
:
:
:
I'm still a little black and blue from the last mugging, I'll try for a few broken ribs this time around.

What comes after the source can only be corrupted by more electronics, it cannot fix a "bad" cdp dac or cd. It can only add corruptions, colourations, distortions and euphonics.
There is no magic preamp that can add bits or remove distortions from a cd or re-design a bad output stage in a cdp or dac, you can however falsely add colourations, euphonics, and tonally change things, but this is not "being true to the source".
I believe if you have a source that needs this sort of treatment, you need to get a better one, and one you like, without having to bandaid fix it.
Cheers George
George,

If they don't get that explanation, they ain't gonna get it.

Lots of folks may prefer an active preamp, me included at times. But your explanation above is about as simple as it can get.

Georgelofi,
What comes after the source can only be corrupted by more electronics, it cannot fix a "bad" cdp dac or cd. It can only add corruptions, colourations, distortions and euphonics.
There is no magic preamp that can add bits or remove distortions from a cd or re-design a bad output stage in a cdp or dac, you can however falsely add colourations, euphonics, and tonally change things, but this is not "being true to the source".
I believe if you have a source that needs this sort of treatment, you need to get a better one, and one you like, without having to bandaid fix it.

Every component has a sonic signature. It's not bad or good but just a sonic signature. By the time signal reaches the preamp, it has sonic signature of the source and IC. The signal still needs to pass through the amp, ic, speaker cable, speakers, PC .... and will get altered and altered again. In a sound system, you are hearing a combination of 10+ sonic signatures, not just the source and interconnect.

Let's try this, apple juice is the taste all the chefs want you to experience. Once it's mixed with 9 different juices, you are tasting a combination of all the juices. Use water for LSA and is added after the apple juice, apple taste is preserved until you add the 8 different juices. At the end, the taste is the combination of all the juices. Now if the 9 juices have the properties of water, NEUTRAL, then apple will be prominent. I guess this is the reason everybody claims their product is neutral.

It appears my view is more at the system level than yours.


01-03-11: Pubul57
Which Shiraz?
2buckchuck.

Wine is like audio. Price does not equate taste. I have 2 friends that own liquor stores, even with discounts I was spending too much $$ on wine over the years. I was reluctant at first but after I tasted 2buckchuck, I sold ... ok I won't list them :-):-) This is what I drink most of time at home. Doesn't taste like an cheap wine but actually best many more expensive ones.
If you like the grape, you'll like the wine 98% of time, no matter what the $$$.
Maybe true to the source should be more about the least coloration added to something that's been colored from the beginning. By that I mean we need to take into account what the recording engineer adds to the mix before it gets stamped as a disc or a piece of vinyl and can be played on our sources. Lets even go further, the instruments played by the musicians add color to a recording whether by composition (ex. wood) or effects(ex. tube guitar amps or feedback).

From a recording perspective, not all recordings are made live in the studio or venue. Although I enjoy those types of recordings best. Many times the musicians that play on a recording are not even in the studio at the same time when their parts are recorded. Then take into account all the equipment and cables used, as well as mixing/EQ.

Knghifi's point is valid, everything contributes to the sound we hear. It's a system after all, and for me the system should offer the least coloration possible. I've told many of my firends that the reason I prefer passive preamps is that our systems already have more than enough gain, why add more to the mix. Seems Nelson Pass said pretty much the same thing in an excerpt from one of his designs philosophies that I quoted in a previous post. If I can eliminate one source of coloration from the mix I figure I've taken a step in the right direction (for me anyway).