Thanks for your comments Bill. I'm glad you enjoyed listening to the LSA. I'm missing it myself so I'm also glad to hear it will be returning to its home:)
I find your last comment on the potential for too much of a good thing an interesting one. I've sometimes felt that depending on various components being assembled, this can occur. I also sense a difference using the LSA with my Atma-Sphere versus my VAC amps. The former combination is much more transparent, the latter adding a touch of warmth and bloom to the mid-range. I'd say my Music Reference RM-10 MkII is somewhere in the middle, closer to the Atma-Sphere than the VAC. I enjoy all the presentations. One not necessarily being better than the other, just different.
Personally, ever since I listened to my first passive preamp (a custom built K&K Audio TVC) I have felt active preamps are additive (some may offer more transparency than others, but in the end they are adding something to the mix). I even felt this way with my old TRL preamp. In the end that's just my opinion and I'm sure there will be some disagreement on that from others here as we all have our preferences. |
If you're inclined to come out West you could sure stop by. Think CES/THE SHOW. Ralph will be in town as well. He's mentioned I should hear one of his preamps in my system with the S-30, especially using the balanced phono inputs. Maybe I can convince him to drop by too. |
Wasn't one of the active buffer designs posted on the DIY forum a tube version? I recall seeing the one from Nelson Pass as well. |
Straight wire no gain? LSA the watercourse way (sic)? Lead, follow, or get out of the way? Sounds likes the LSA fits the bill;) However, it doesn't fit everyone's preference.
In any event, with the LSA we're not only left with the source-amp-speaker interface, we're left with the recording engineers/musicians preference. I have never heard a preamp that exposed that extra variable into the mix like the LSA.
True to the source? Perhaps... |
That was Paul's prototype of a battery-powered, solid state pre right? Not a Dude. Out of curiosity, did you ever hear the LSA side to side with that entity? Are you speaking from sonic memory? It was the Pre-1.5 battery powered preamp and no, I never compared it with the LSA. My comment was a blanket comment on all the active preamps that I have heard since I have been exposed to what well designed passive preamps can do in ones system. To me they are all additive (some more so than others), not necessarily in a bad way, as I do enjoy listening to some active preamps. Again, it's my opinion and anyone can feel free to agree or disagree. Perhaps the Dude is different and maybe some day I'll get to hear it for myself and come to my own conclusion. After all I lent my LSA to Bill so he could do exactly that. |
For some reason, I'm not tempted to use the LSA with the Atma-sphere (M60s). You really should try it. You have great synergy with the Atma-Sphere combo, but I think you would enjoy the LSA with it too. |
Well said George and especially Paul.
Hopefully the LSA will make an appearance this Friday or Saturday at RMAF. I would love to set it up in a few different systems while I'm there. |
Great post Dave. Regarding the allegation of "forwardness," assuming that we are not talking about strident aggressiveness, the quality of forwardness in a top component is often a good thing in the sense that the piece sounds more alive, faster, dynamic and resolving. The listener is literally closer to the music, in fact the stage may extend both forward of and to the rear of the speakers. In this scenario depth-of-field cues are delivered through high resolution. Instruments appear layered in depth more by virtue of low-level cues than by soundstaging per se. I have a recording that illustrates this very well. The soundstage is very deep, yet the piano is quite forward in it. The vibes float effortlessly in the middle with amazing lateral movement. On some tracks the soundstage does in fact exceed the speakers. The CD is The Wonderful World of Ron Carter and IMO is well engineered. Anyone who enjoys jazz trios with excellent bass playing should look into it. The music will certainly give your system a lower frequency work out if nothing else. |
I agree, the issue of transparency is more black and white. I think it is as simple as this:
1. The Bolero test can indicate if your system is passive friendly.
2. The Bolero test can indicate the level of transparency a preamp possesses, active or passive.
3. You may or may not like the results of #2 above based on your preference.
The first two provide a means to generate pretty accurate test results. The third is the human element added to the mix. Bill has ascertained that his system is passive friendly and the LSA possesses a high level of transparency (but only subjectively). However, Bill has stated what his preferences are and what they are based on (whether we agree or not is immaterial). Bill has determined the Dude meets his criteria, regardless of whether tests reveal that it may or may not be less transparent than the LSA (as far as I know, he has not made the comparison between the Dude and LSA to the Bolero test). End of story.
Personally we all know where I stand. Lots of great points made here many of the parties involved. To Pubul57's comment, maybe we should rename this thread Lightspeed Attenuator - Preamp Deal of the Century. Might give the other thread with a similar name a run for its money. After all this piece of equipment cost a lot less than the other deal of the century and is still in general production. It has less parts and no active circuitry to cause reliability issues either.
Oops I did it again... |
George, aren't the Burson Audio buffers an FET design that does not use ICs? Their RCA version includes a volume control too. Curious as to why the balanced XLR version doesn't. Might have liked to the balanced XLR version give a spin with my Atma-Sphere amp. |
Wilsynet, glad you were able to put together this combination. It is incredibly good for the money. I have about $1500 invested in my LSA and RM-10 MkII. That's tough to beat for SOTA sound.
I've been listening to the LSA with battery power supply for a while now. I would suggest to anyone that owns one to give it a try. The parts cost is less than $75 (here in the US anyway) and it's plug and play. Also, I've been using my LSA with the Atmasphere S-30. Now I'm tempted to break out the RM-10 again. |
Bill, I'd certainly love to hear those Sound Labs in a good room set-up. I have heard them at audio shows and once at a local Chicago area dealers home. The latter was a very good experience, but not ideal IMO.
Your point you made in your other post is very clear to me, but I happen to agree with Pubul57 on this one. Six of one half a dozen of the other. |
Paul, I'll be attending the party for a little bit this year seeking out some folks to say hello. I'll be getting over to Del Frisco's Double Eagle Steakhouse as well. There's a bottle of Silver Oak Cabernet with my name on it courtesy of friend. Can't miss out on that.
Some good after hours events in the rooms too. Thom Mackris from Galibier Design (I use his Serac turn table) is doing some fun stuff. I'll be staying in the Concert Fidelity suite as their guest, so I'm sure we'll be keeping the music going a bit past 6pm. It should be a very well attended event.
Keep CES/THE SHOW in mind. If you've never been to it this is a great time too, although somewhat more exhausting than RMAF. We have a Del Frisco's here too:) |
Catastrofe and Pubul57 hit it.
I don't care how hard you try, even if you put considerable investment ($$$$$) and built a custom dedicated room you would not get anywhere near true live sound. You stand a much better chance of getting the true essence of the recording, or at best something that meets your listening preferences and is pleasing. There's nothing wrong with that either. I've been in some really nice listening rooms too, but the replication of live sound (even on a live recording) is not what I hear. Great sound yes, live sound no.
Personally, if you want to replicate live sound go build/buy a studio, club, or music venue and book live performers. If you're going to do it then do it right. |
CES is huge, think downtown Manhattan in rush hour. Proper planning can assure you get to see what you want, and potentially in off-peak hours. The rooms are good size and I find the set-up done properly can sound very good. It can be intimidating at first, but overall not so bad. IMO it will be proportionally worse space wise at RMAF on Saturday when you get the full impact of the outsiders and locals attending. The Venetian will be crowded, but there's more space to work with overall.
I think the jewel is THE SHOW. Last year it was at the Flamingo and was done very well IMO. You'll get more boutique manufacturers, less crowds, and can cover more ground in less time. The kicker would be if the NSF exhibit room is on for this year. An audiophile(s?) rents the space and provides a funky lounge atmosphere (no pun) with adult beverages and music. Last year John DeVore had his speakers in the room and the rest of the system I believe was supplied by the sponsor(?). Played lots of vinyl too. THE SHOW is where Ralph sets up shop, as does Brian Cheney (VMPS), Audio Note, and a few other notables. |
The Audio Note UK room is always well done. They crank up some rock music on that system too which sort of surprised me. Sounded really good too.
As per the last couple RMAF shows Ralph's equipment will be in the Galibier Design room. Arguably will have some of the best analog sound at the show. |
I agree with the assessment, although some tube rolling could change that. Pubul57 might be able to share more on that as I believe he has done some tube swapping with the amp. I use the stock tubes as supplied by Roger and the way Srajan describes it is how I hear it. FWIW and if IIRC, Roger designed the RM-10 using Quad 57 speakers with it for his listening tests. There are some other interesting design characteristics about the amp that fly in the face of typical amp designs and how we audiophiles associate various sound qualities with them.
Tvad, if you're interested in hearing the RM-10 let me know. I'm not using mine at the moment. If possible I'd like to compare the RM-10/LSA combo versus RM-10/VRE-1 combo. |
Off to the closet to unpack the RM-10.
I light load my RM-10 since my speakers are 12 ohm nominal and don't dip below 8. Anyone else light load their RM-10? |
Light loading is supposed to make the amp more linear, with significantly less distortion, and more headroom. Yes, there will be less power (negligible in my case), but the damping factor doubles. My speakers are rated between 8 and 12 ohms, so while I've used the 8 ohm taps on the amp, I'm not sure I'm getting the same benefit of light loading as others who might be using the 4 ohm tap for their 8 ohm speakers. Perhaps using the 4 ohm taps would be better. I'll go over to Audio Circle and post the question over there. |
The extra power is certainly a consideration in easy to drive speakers. However, the other benefits of light loading should be considered as well, namely lower distortion and increased linearity and head room. If your speakers can handle the loss in power, roughly 7 or 8 watts, in exchange for the increased head room why not try it.
FWIW, I was listening late last night with the speaker cables connected to the 4 ohm tap. I didn't notice any loss of slam or dynamics and I was listening at considerably lower volume. Maybe I'm mistaken but wouldn't that be an effect of increased head room?
This combo is certainly very special. I wouldn't let the single input/output stop you from running it with multiple sources either. I have no problem swapping cables between digital and my three analog sources.
Question for George: In comparison to my Atma-Sphere amp which is less sensitive and has less gain the RM-10 doesn't require me to use as much of the volume control. I seldom get past 12 o'clock and most CDs come in around 10 - 11 o'clock for normal listening. Any potential sonic issues one should be aware of. I would think not base on what I'm hearing but thought I'd ask anyway. |
|
It's nice to deal with someone with a HONEST and accurate estimate. No BS why estimates are constantly revised ... blab blab blab LOL...*wink* *wink* |
I believe the TRL amps are over 47k ohms, somewhere in the 65k ohm range, maybe higher. |
I can't say for sure about the Samson, but my TRL D-225 which was the predecessor and stereo version of the monoblocks used bipolar transistors. Paul Weitzel told me he does not like FETs or MOSFETs. I do believe what Knghifi has reported is accurate with the specs TRL provides on the amps. |
If you think this thread is long in the tooth go over to the one on DIYAudio. It makes this one read like a short story. |
Banquo363,
Steve builds quality products at great prices. I'd be surprised if you could hear a difference using his input selector. He uses quality parts and backs it up with a 30 day trial (stock units, not custom orders).
I was pleasantly surprised with the interconnects. I've tried one of his phono stages in the past as well and would love to try his speakers some day. I'm not the best customer he has, far from it in fact, but if I call and talk to him he will spend whatever time he has to with me. Great person to deal with. Tell him what you're going to use the input selector for and he'll shoot straight with you. |
This is OK right? The Lightspeed is also a good preamp, but won’t win every a/b shootout right?
Your thoughts? Of course it's okay and I wouldn't expect it to win every shootout. The fact it can favorably compete with preamps that cost at a minimum 10x as much and in Knghifi's case significantly more is an extremely positive statement all by itself. Let's not forget that it beat out some great preamps too. Just for the record, it's been stated numerous times in this thread that certain conditions must exist in order for the LSA to work optimally. I don't see any harm in questioning whether those conditions existed. It's critical to ensuring the LSA was evaluated properly. Assuming it was, and both Knghifi and I both verified as much by indicating the proper specs for the amp, then you're right, it comes down to preference. |
What I understood from George's comments based on his experience was that bipolar designed circuits would not typically have a 100k input impedance and many examples of this design had less than the 47k ohm the LSA requires, in some cases significantly less.
Could it be possible to design a circuit using bipolar transistors that is an exception? Obviously the answer is yes assuming the Samson specs are accurate and I have no reason to believe they are not. I'm basically accepting the designers statements at face value since I don't have the amp myself to take a measurement and lack the necessary experience to refute the claim.
In somewhat of an analogy Roger Modjeski wrote an application for an EL-84 circuit that gets at least twice as much power than others have been able to achieve using the standard circuits published in books. So perhaps this is a new twist on a standard design that allows for a higher than normal input impedance. The only people who can actually tell us are the designer or an owner who has the ability take a proper measurement. Personally its hardly worth the trouble. |
I am talking about honest dialogue here and not about product cheerleading. I would have not posted a thing if the builder did not quickly run to the catch all "bad synergy" comment on Knghifi's Samson amp. According to the amp's spec it is indeed good synergy. I simply want accurate and productive discussion that is open to the facts. I think you're reaching on this one Bill. George was curious as to what the load was on the Samson. He couldn't find any specs and it's well known that TRL doesn't publish them. So all he had to go on was his experience. Here is what George actually said: One question Knghifi the poweramp TRL Samson you used for the comparison, it's a solid state amp and I have looked everywhere for it's input impedance and nowhere can I find it, as the Lightspeed Attenuator likes to see 47kohms or higher for the poweramp it's feeding. If the TRL is lower than this you have still not heard the Lightspeed at it's best, and heaven forbid it may beat out the VAC Signature if it sees an amp with the input at 47kohms or higher. Where's the cheerleading there? Where is the dishonest dialogue? Again, he indicated what has been said here and elsewhere about LSA requirements. Had the specs been published and he could of seen them I'm going to assume we wouldn't be having this conversation. He would have known right off the bat that the input impedance requirements were met. I don't see where Knghifi is being attacked (pretty strong word don't you think). As for you being attacked when reporting your findings IIRC correctly there was a lot of confusion in that dialogue regarding the definition of transparency. Yours being different than what others here including myself interpreted as the meaning. We all stated our opinions and preferences. Personally I found it a pretty interesting dialogue and it made me think about how I listen. This thread has had a pretty decent life. Sure it dies down but it always comes back. I think it's done a good job of opening up some peoples eyes as to what is possible sound wise for such little investment. As Fiddler indicated there is a fair amount of cheer leading in the forums, take for example the Supratek and Audio Horizons threads. Do you happen to recall these?: http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1142509250&openflup&2&4#2http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1016931418&openusid&zzGrannyring&4&5#GrannyringThese are just the first posts I ran across. I'm surprised there isn't a "Dude best preamp" thread on here. Maybe there should be. If there was I'm sure we'd see our fair share of cheer leading, as well as a lot more controversy than what we've seen here based on past TRL threads I have read and participated in. Heck it probably would get deleted just like the last TRL thread on the digital forum. |
That explains a lot, thanks for following up George. |
$13,550 is a lot of spare change. The way things are going right now I might be able to turn that into $50,000 here in Las Vegas by the end of football season:) |
Betting against the Giants has been very profitable the last two weeks. I think we're going to take the Redskins this week as well. |
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... |
Perhaps it is simply getting out of the way and revealing with the RM10 can do - the combo may be a very, very good match. That's a big part of it, in addition to remaining true to the source. I've not yet tried the LSA with my Atma-sphere amps because I have a lot of 6sn7s and 12au7s for my Atma-sphere preamp, and I'm not sure the M60s will be sensitive enough to go passive. They are sensitive enough, trust me. What is the LSA does exceptionally well, where I really see it shine is how right it gets the timbre of instruments, wide and balanced frequency range (plenty of bass), and dynamics. I don't hear anything remotely like 2D sound staging, width, depth, and relative positioning (layering?) seems just about right. The designer of my speakers top priority was getting the reproduction of natural timbre right. Putting the LSA in the chain did nothing to disrupt the natural timbre being reproduced by my speakers. It's one of the reasons the LSA is a hit with me. I agree on the other comments as well regarding dynamics, tonal balance, and sound staging. I'll also add I notice much more how the sound staging varies by recording. |
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. |
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. |
Whoa, this is getting deep. I just came back from setting up our room at THE SHOW and wasn't ready for this. I need a martini and then Ill come back to it.
Maybe we should rename the thread Tao the Lightspeed Way. |
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. |
Nelson Pass indeed has given a lot to this community as is evidenced here: Pass DIYIn 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.htmIf 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. |
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. |
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;) |
Funny, I just pulled the RM-10 MkII out of the closet as well. Such big sound from a small piece of gear. A wonderful synergy too with the LSA. It just gets out of the way and lets the amp do its business. |
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:) |
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).
|
Well that first one of mine turned into three and the rest was history.
Going to be a real busy week working two rooms at THE SHOW. The Concert Fidelity, Electra-Print, and Atma-Sphere rooms are in a little triangular area (the first to are the ones I'm working), so it's going to be fun hanging out with all those guys. Too bad I'm probably not going to have time to go over to the Venetian.
Hopefully you'll not be speaking in tongues by the time I get back. |
Perhaps a passive is, well, “too passive” to extract all of that information (on the source CD etc). This requires an “additive” (accurate gain) approach. Our stereo systems must be “additive” to even play a single note through a speaker. A passive may simply leave these higher order musical realities out – they may be subtractive.
Grannyring Passives don't extract anything. They just pass an attenuated signal. Your source is extracting the music off the medium. Systems do have to be additive to play music. There should be enough drive from a 2V source and enough gain in your amps to accomplish this. Anything more is excess IMO. The only way a passive can be subtractive is if there is an impedance mismatch. If you are missing depth, body, and dimension with a passive well... |
Selling the circuit diagram? Seriously? No April Fools joke? Never ceases to amaze me as to what some will do to make a buck. |
I had a good impedance match with the Atmasphere MA1 amps (100K ohms) but the resulting sound was relatively flat as I have already said. So impedance matching was not all the issue.
Grannyring Yes I agree looking to 100k ohms the LSA would be a good match impedance wise. That wasn't what I was referencing in my last sentence of my previous post. I can't see how a preamp, active or passive extracts anything. Someone is going to have to educate me on this one. The information is already extracted from the medium prior to getting to the preamp. I don't think it gets extracted any further at that point. Depending on the type of preamp other things could happen to the signal, but as Fiddler said it would be additive, or as you said, it could be subtractive. |
If you need something that can drive long interconnects and provide impedance matching there are still active buffers like The Truth, Pass B1, and Burson Audio that will get you there while still providing a high level of neutrality.
The long interconnect advantage is really only valid for active preamps that are true balanced designs. Most audiophiles are running single ended systems and while you might be able to stretch the interconnect a meter or two further, I suspect it's the color of the month they're really looking for. On top of this perceived notion that 10db or so of gain is going to make a real difference in dynamics, slam, and 3-D presentation. |
What I find amusing are these threads where people complain they can't get past 9 o'clock on their volume control. They're looking for a way to get more control over the range. In some cases they end up buying Rothwell attenuators to get a 10db reduction that gets them to 10 o'clock instead.
Several posts above I quoted what Nelson Pass had to say about the psychological dimension to the perception of power and drive. Seems he figured it all out a while ago. |
