Thanks George, what about a battery PS.
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.
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.
1,866 responses Add your response
Hi
clio09
, that one you've linked to is not one I've seen before, as at just 8.5v it's close to the drop out voltage (7.5v) of the 5v regulated circuit inside the Lightspeed. For $50 it's a good buy though, and should be fine. The ones I used to link to, were 9v and I think you could adjust them to 12v inside, with a trimpot, maybe you can with this too. Cheers George |
I had some time to kill so I decided to re-red this entire thread (I sure do miss Paul). I'm not on Audiogon much anymore, but have to say that the Lightspeed is still with me and getting its fair share of use. I've been looking to upgrade the PS so went looking for a Teradak and found this one: https://www.ebay.com/itm/TeraDak-U9-Linear-Power-Supply-DC-8-5V-1A-USB-5V-1A/302532038401?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649 I assume it will work based on what I have seen in previous comments here. On the other hand, what's the best batter PS option these days? |
tradeontheweb I dug out some noise measurements for you guys I did on the noise floor of the output into 50kohm load. It was on the absolute limit on my Tektronics test gear to measure down that low. And with the Linear powersupply it was 50uV P/P (micro volts peak to peak ), this is around ten times lower that the best active preamps I’ve seen, which are sometimes in the mV (millivolts) Then I did the same using a pure battery supply, and yes it did come down a touch from 50uV to 30uV, this could be the reason some of us hear something when using battery but can’t explain what? But a difference of 20uV (micro volts) noise is practically nothing?? I can't point my finger at this and say this is what we're hearing though. Cheers George |
mickstuhhttp://www.beone-audio.com/eindex-1.htm Wow these guys look to make some good stuff, a bit like Usher. Some of the speakers are very Sonus Faber influenced. Cheers George |
In answer to your question Georgehifi , my speakers are Be-One, model: The One. No one has ever heard of them; well, not in the West. I heard them and bought them. I have only ever found one reference online, by a reviewer (an amateur, I think), who had them as his reference speaker. The site where I read that seems to have died. The brand is Chinese, and have a website beone-audio.com. It often works. My speakers have been discontinued, and removed from the site. They most resemble the BO-8, which has one less driver per cabinet. I have never heard their amps, but they do look gorgeous! Hey, if you are ever in the Dandenongs ... |
tradeontheweb thanks for the guidance. I may try the battery option too as a fun experiment. I've started out powering the Lightspeed with a Teradak power supply. I hadn't done any upgrades to my setup in about 10 years since I recapped my AR9LSi speakers with audio grade film caps. I thought I was done, but started sensing something was holding me back recently. I started researching what folks were saying about the components that I already had and discovered folks saying the Adcom GFP-565 was not very good. Glad I found the Lightspeed. It totally makes sense that putting more active components between the music source and the amp risks adding more noise to the signal. It would have been another long journey to buy and try a bunch of different active preamps. The Lightspeed has also rekindled my audio bug too. Will be looking at further upgrades or mods to my other components, but the Lightspeed will remain at the core. |
BTW: esmith904 You can also try to power it using rechargeable battery power, (links are somewhere here to get one on eBay). Most (including me) say it’s better than the wall wart, but there’s not much in it, just a feeling. As they can’t explain what’s better, but it’s definitely worth doing as they are cheap to get. |
Welcome to the club esmith904 ! Your description kind of mirrors what I remember mine was, more than 10years ago now. I’d thought I was doing well with my system. Big Infinity Speakers, couple of Krell amps and a Cal CL-15 HDCD/CD player. I’d used a variety of solid state and valve preamps, including Musical Fidelity, Audio Research SP10 & 11 and most memorably, a very "microphonic" Supratek valve Pre. Some were great, some less so, but all imparted their own coloration to the sound. I actually borrowed my first Lightspeed from a friend. On first sight, it wasn’t impressive at all compared to the monsters I’d used. But connecting and listening dispelled any concerns I’d had on the appearance. As you say, clarity, cleanliness and dynamics are there in spades. I don’t care what it looks like, I bought one there and then. At the price, it’s one of the real bargains in high end Audio and let’s face it - they’re few and far between! I don’t know whether we’re in a "secret"club any longer, as I see more and more comments on it here and over at DiyAudio as well. Anyway, nice to see another happy Lightspeed’er on here! |
Sharing my new experience with the Lightspeed Attenuator. I've recently been researching what key upgrade I could make to my mid-fi Adcom setup (Cal Audio Labs Icon II CD, GDA-700 DAC, GFP-565 preamp, GFA-545 II amp, AR9LSi speakers) in an attempt to approach hi-fi sound. After much web searching and reading reviews, I determined replacing the Adcom GFP-565 preamp was where I'd get the most sound improvement. However, most of the recommendations I could find suggested I'd need to step up to $3K-4K active preamp or give a passive a try. Luckily, I stumbled across this thread with glowing reviews how the Lightspeed is as good or better than very expensive active preamps. My experience so far has blown me away. I didn't know recorded music could possibly sound this good. The sound is super clean, clear, more 3 dimensional, and has more bass at low volume. The music seems to have more impact from individual instrument sounds at moderate listening levels. Seems like I can feel the music more. I can really tell a difference in the sound of cymbals now have a clear metallic shimmer vs. a fuzzy sizzle. Everything just sounds better across the spectrum. I'm buying another one for my office system. I feel like I've joined the secret Lightspeed club. It's hard to believe something this good is not that widely known. |
mickstuhHi Mick, thank you very much for the glowing review, especially with your equipment the Lightspeed is keeping company with. I've tried to Google these speakers but found very little on these 100kg beasts have you a link to them? As for the slight impedance mismatch, the worse scenario output impedance for the Lightspeed is around 2.7kohm, if the Schiit Sys is a 10kohm volume pot this should be about the same. And yes even 2.7kohm output impedance into your Halcro's very low! 10kohm input impedance, it will be at a slight disadvantage, this is why you liked the extra drive the X10-V3 a little more. But if the Halcro had say 33kohm or higher input impedance, you would probably have preferred the sound without the buffer in circuit. As the best buffer is no buffer still if you don’t need it. Cheers George |
toddverrone Hi Todd. Yes it would be, but here’s the problem I have. The Lightspeed is all about not have any light contacts in the signal path, this includes volume controls and yes input or output switching. My prototype still measures and sounds as good as it did when new, but it has got two inputs with switching (WHAT!!! you say), it has the best switching/wiring possible, because I need to A/B dac I/V stage modifications which I also do on the side as well. This this prototype Lightspeed is the benchmark test for all production Lightspeeds to be A/B’d against with before they are sent to customers, to make sure they all perform as expected. From even when it was new everyone that has heard the A/B’s including me production ones vs the prototype, says that the production ones with only one input sounds just a little better You can’t put your finger on what it is, but the productions ones have just a touch more ease/transparency to the music presentation than the prototype. It’s a bit like when you hear the battery supply vs the mains supply, you have a feeling the battery is just a touch ahead of the mains. This is the reason I don’t do input switching, as I want the production Lightspeed Attenuators to be as transparent as possible, without any compromises done in the manufacturing process. Cheers George |
I’d been searching for a preamp, so for a giggle I Googled “best preamp ever audiogon” to see to see who had recommended what. The top hit was for tube preamps, but I didn’t want to limit my search to tubes. The second-top hit was not it either – just preamps for sale. But the third and fourth hits were more like it. They came from this very thread. I started reading. My reading extended over two nights. (Thanks guys!) My interest turned to intrigue when I twigged that the preamp – the Lightspeed Attenuator of course – was Australian (which is what I am and where I am). What really kept me reading was seeing actual users were replacing expensive and much-loved amps – tubes even – with something straightforward and cheap (by comparison). Now, the OP here (thank you Pubul57) had made it clear that the Lightspeed needs the right environment in which to work. A source ouputting 2V or more, which is pretty much everything these days I believe, a short interconnect to the power amp (three metres or less), low capacitance interconnects – and a power amp whose input is preferably the industry standard of 47K ohms or more. I checked the specs on my Halcro DM38. Only 10K ohms on the RCA input. The Lightspeed outputs RCA only. That might be a problem. But I wasn’t going to stop now, was I? Just to test before shelling out, I plugged my passive Schiit Sys into the Halcro. The Schiit outputs up to 5K ohm (not dissimilar I believe to the most the Lightspeed puts out). So we are a long way from the ideal 1:10 ratio, which would have us up around the 47K standard. But the Schiit provided enough bass and volume to make me push ahead. It worked, at least. But I thought I was probably going to need a buffer, so as to fix the impedance mismatch between the Lightspeed and the Halcro. And I should detail the rest of the system. Speakers are a massive pair – Be-One, The One. Five drivers per cabinet, about 100 kgs each, sensitivity 89db. Streaming via an Auralic Aries Mini, listening to 320 MPs, CD rips, hi-res files and DSD. Switching between DACs – the Aries, an Emotiva and an R2R Audio-GD 11. Preamps on hand for comparison were the Aries Mini again, a Xindak XB 8250, and a Geiseler preamp (another boutique Australian product) (and the pre-outs of a few integrated, including a Jungson JA-88D, Yamaha AS200, Harmon Kardon 990). There were two tube preamps around, an Audile using Jan Philips 5814a tubes, and a SoundMaster Mk 23 using 2A3, but the tubes were so different, I didn’t make comparisons with the Lightspeed. The room is roughly 30 foot long and 12 foot wide. So the Lightspeed arrived. One great thing about it – no burn-in. Because there is nothing to burn it. That’s a relief. Just give it one minute to get warm. We’re off. First impressions: this is good. It was clear. Like water. There was no shortage of bass. Or volume. Highs were clear. Volume – more than enough. I had it playing around 2 o’clock to play it loud (90db, sitting four to five metres from the speakers.) There is no sweet spot on the volume dial – the sound is the same all the way. There was no channel imbalance. That’s what it sounded like – which is to say, it had little sound of its own. It was dead silent – which I suppose is a function of no gain and no mechanical parts to speak of. My room is very quiet, so that silence is impressive – and necessary. Whenever I get a new component, I make a point of listening to it. By which I mean, not comparing, but listening. (And I only change one thing at a time – so I can be sure where the difference is coming from.) So only after a few days did I start to compare – with a little bit of fear. Comparison confirmed my suspicions: what the Lightspeed delivered was good, but insufficient. It was approaching the weaknesses commonly attributed to passive preamps. The attack on notes – be they guitar strings or piano notes or kick drums or electronic bass bombs – wasn’t quite there. That one thing amounted to the music losing life and shine. But what was there was all good – it just felt the thing was struggling, pushing the music uphill. But it was clearly good enough that I had to know how it would sound given the right conditions. So let’s get a buffer. I got a Musical Fidelity X10v3 (not XD.) It puts out just 33 ohms. It deploys two military-spec tubes – which Musical Fidelity says are designed to withstand the radiation of a nuclear war. Pity the rest of the system won’t survive. And, voila. Now we’re talking. If the taste was water before, it was water out of a plastic cup. Now it’s water out of quality glass. Transparent. All the life and dynamics were there. Transients had zing. Slam had slam. If the recording has depth and height and placement (ie soundstage), so does its reproduction. It just sounded like I was hearing the music – be it Billie Holiday, Kraftwerk, Crazy Horse or Chopin. The lack of distortion from both components is quite the treat. So, there you go. This will be old news to some of you – but I had to share it, and the odd fact that I had to go so far afield to discover something in my own backyard. This thing really is ingenious. Theoretically, it seems to me the ideal preamp: adding nothing, subtracting nothing, with no touching moving parts and no noise, simply providing a channel through which the music can flow. Like straight wire with gain – except there’s no wire, only light dependent resistors, and no gain either. |
hopkinstk That’s an impressive list of gear you have there hopkinstk 1: Two Spectron Musician III MKII in mono blocks 2: Usher BE-20 Diamond 3: VPI Prime turntable with Dynavector xx-2 MKII cartridge 4: Whest PS.30RDT SE Phono Stage I have a buddy that also has the Usher BE20’s and wow they are very good and full range to boot, I couldn’t see that the Rel sub would be needed with them they go so low. (maybe from 30hz down? if you listen to a lot of organ recitals) I’m pleased you think so much so much of the Lightspeed Attenuator passive pre to keep it in that company. Cheers George |
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This is my impression of the Light Speed Attenuator (LSA) in my system that consist of the following equipment:
Previous setups: I was using the Sonic Euphoria Passive Line Controller (PLC), the Sonic Euphoria PLC is a passive preamplifier using an autoformer attenuator. The Purist Audio IRD LLC-P Preamplifier, also the Axiom passive with modifications to the internal wiring with Mundorf sgw110wh wire, a mixture of Silver and 1% Gold. The closest of the above passives that came close to achieving true non coloration of the sound and delivering only what was in the recording was the modified Axiom passive. I researched the Light Speed Attenuator and found interesting comments from owners that ranged from outstanding to not a great fit for my system. Due to prior passives having plenty of gain for my system, I contacted George and made the purchase. It arrived in Texas within the two week period he stated he needed. He provided outstanding technical support and even researched the problem I noticed with integrating my Rel R528 SE subwoofer into the system. For some reason using the Neutrik Speakon connector from my amp to the Rel caused issues with the LSA, which to me sounded like an impedance matching issue. (I do not miss the Rel with the LSA, there is plenty of deep articulate bass with my Ushers alone, but will be searching for a fix). LSA Power Supply: Adding the LSA to my system was everything I have been trying to achieve in my listening room. I decided to power it with my HDPLEX 200W Linear Power Supply vs the wart linear power supply due to the fact that it has a dedicated XLR---5.5/2.1mm Connector Cable. Perfect for the LSA and provides Top of the Line Hi-End Audio ELNA Capacitors, High Quality 200W Silent R-Core Transformer provides clean energy, Separated Ground for Each Output Rail, EMI/RFI Circuit to Prevent AC Grid Pollution, No Humming or Buzz noise for 50Hz and Peak load, 100% Silent, High Quality Neutrik XLR Connector for All Outputs, and Low ripple noise and void of high frequency noise. LSA Addition to System Sound: There are details in the midrange and treble that are just more obvious now. The treble seems more extended, but there was absolutely no change in tone from what is on the album. Vocals are even more realistic, and everything has increased texture and is more palpable. But the best thing of all is the increased speed of transients. Everything has an immediacy to it. This even translates to the very deep articulate bass. Kick drums have speed and an authority that is impressive. The entire sound stage is one cohesive unit now in my system. There is a tremendous amount of fast energy. This is consistent on all tracks played. The music has real life and intensity. It is extremely quiet, musical, and detailed with a large soundstage and is very well focused. I consider it an outstanding value for its price range. The best I've heard in my system to date. I perceive no loss of dynamics at any volume. I can load my room adequately at around 9:30 or 10:00 on the dial. I have plenty of headroom and absolutely no distortion at insane volumes. The bass has never been as good and the separation and blackness are vastly improved. You feel the real image of the instrument’s size and acoustic quality with all analogue recordings I have played to date. Advantages of the LSA: With the LSA in my system, I have noticed that setting the proper VTA on the fly with the VPI Prime on each record to optimize playback is very easy and the changes are easily heard without the use of headphones for precise imaging. From https://londonjazzcollector.wordpress.com/for-audiophiles/tonearm-vta-adjustment/ “Precise adjustment of the Vertical Tracking of your tonearm is one of the most significant improvements you can make to your listening experience. It is not as difficult as you may be thinking, and costs nothing. You have already paid for your equipment, and though the turntable may have been set up “perfectly. In less than 15 minutes, the effect of adjusting, refining the adjustment, and eventually locating the “sweet spot” in VTA – just a turn of the adjuster, listen, turn a little more, listen, turn again until you finally locate it – completely transformed the performance of the system. The stereo sound stage snapped into focus, the troubling bass lifted, harshness was replaced by sweetness, an extraordinary and unexpected experience.”
Please understand that this is my experience with the LSA with my equipment. |
Thanks for that in-depth review water111 . If any reading who have the skills wish to construct one for themselves as water111 did, instead of purchasing the ready made Lightspeed Attenuator, my first original post is here to do it with. http://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-new-passive-preamp.html#post924390 PS: you may have to join to see all the attachments, circuit diagrams ect. I’m always available on this Audiogon Lightspeed thread for any help you may need, PS: I do not sell kits or parts as they are all available for diyers to get themselves. Cheers George |
My review….. As an ex-owner of many hi-end audiophile hardware from speakers such as Kharma, Dynaudio, Vandersteen, Magnapan, Sonus Faber, to amplifier such as Audio Research, Plinus, Rogue, etc I am experience and qualify to review hifi component, up to S$50K if putting a value to a piece of hardware means anything to you. Lightspeed is a product that appeal mostly to the diy community. By saying diy community I don't mean only those who seek to build an attenuator only but also those who are constantly searching for tweaks to their hardware such as Caps and tube roll or optimising an amplifier circuit. The writer is one such person. LS did no active advertising and I chance upon the LDR circuitry in a diy forum only recently while seeking to improve my channel imbalance with the Alps variable resistor swipe type volume control. I assembled a 23 steps attenuator and realised my Alps variable resistor was indeed a bottleneck to my system. The 23 steps attenuator was like from winter to spring in my system. But I believe much can still be done to improve the performance. Than came the LDR attenuator. A simple and logical concept of using an isolated LED light intensity circuitry to vary resistance in another circuit hence producing a clean signal through the amplifier circuit resulting in crisp, clear, smooth, transparent and quiet layers of music only limited by the quality of the equipment downstream to the LS. The use of the stereotype audiophile jargon such as soundstage height/width, imaging, timbre, etc... is to me irrelevant in describing the LS. I believe an attenuator's aim is not to have a sound but to vary the signal level and pass-through effortlessly and not impeding the potential of your equipment. Any improvement gain is due to your equipment and LS is just an enabler. But I will certainly get bomb to claim the LS do not have a sound because the signals do run through some circuitry before it gets transmitted to your equipment. My point here is that if the LS produce a negative effects to your setup or swing towards certain attributes that is not to your liking, most likely the cause is a mismatch in impedance or you have a coloured attenuator and not the LS being inferior. Is the LS a plug and play component? No and maybe. First you need to make sure you don't have an impedance mismatch issue which is rare but not impossible. I have also a tube pre and SS power system and I lost the much preferred "tube sound" by putting the LS in place of my tube pre. This is not to say that it is terrible but not my preferred sound. I have now bypass my tube pre 23 step attenuator and use it as an over glorified tube buffer. If you are using a passive preamp the LS is a no brainer upgrade. If you have and like your SS pre, you will likely like the LS in place of your SS pre. Comparing my Alps to the LS is like winter to summer. It doesn't sound thin or dry on the contrary to some who have reported their experience. I recommend it highly if it fits you bill. A working LS circuit is available from a diy forum if you are a diy-er or are hell bend for saving up for other upgrade and only if you can find a match pair of LDR out of the many required for a project. I believe I can also make one from the available info from the internet but I choose to support the inventor who is passionate and generous enough to share his circuit and know how to the diy community in the numerous forum in the internet. His generosity proved that he is not a money grabbing person and in today's world such character is few and far between. The LS is where I stop my search for a better alternative for now. Buy it if it fits your bill before you consider an interconnect upgrade, tube roll, power cord upgrade, component upgrade. Most likely it is cheaper than other conventional upgrade path. DIY if you want and George will throw you his float when you are drowning. I hope the Lightspeed reach commercial success in a huge way in the future not that George care if it did or not. PS: I am not affiliated to the Lightspeed product. �N�/:0� |
Genuine TDA1541R1Best way of reproducing pcm redbook cd, with R2R Mutibit converters. Man after my own heart. This intrigues me, as I'm right into zero feedback I/V stages for current output dacs/. Any more info on this, circuit perhaps I/V converter based on the special gold plated low noise vintage transistor Cheers George |
Crazy looking speakers. The Belles came first and the amp followed. About 3w is about right and I listen with the Lightspeed at about 1/3 volume. Very efficient. The DAC is handmade with the following as some particulars. Very interesting though. DAC 2.0SE features: 1.Tube DEM clock (E180F, EAA91) 2.CS8414 SPDIF receiver 24/96 3.Shunt voltage regulators based on the germanuim transistors. The scheme has been improved and has a superior thermal stability. 4. Vintage and modern audio components are used:allen bradley,philips,telefunken, Capacitors:Black Gate (2pc FK series,1pc PK series),panasonic pureism,Audio note standard (2pc) and Audio Note Kaisei(3pc) 220mfX160v,470mfx25v 5.Board covered with gold and a special varnish for best sound 6.Stranded wires composed of vintage copper wires taken from klangfilm, telefunken, siemens sound equipment 7. I/U convertor based on the special gold plated low noise vintage transistor. Because of this fact, an excellent reproduction of quiet sounds, at -60.-80db level 8. PIO output capacitors HYDRA from 60th 9. Shortest signal path, the tube output stage with the low output impedance (5687,EZ80). 10.NOS mode(non oversampling) 11.Genuine TDA1541R1 philips factory 12.Siemens film capacitors in the DEM cells 13.Spdif receiver voltage stabilizer based on unique powerful vintage transistor with a semiconductor crystal on a thin gold basis in the copper case. 14.Separate power transformers for digital and analog sections. Separate transformer for DEM clock. 15.Telefunken choke from 30th in the 5687 power supply. �4���� |
Glad you enjoy it so much Jeff, that is a very interesting system, low power purest, you need the efficiency of the Belle’s for those amps. Can you give some info or links on the dac and amp/s as I’ve never come across these before, I take it the amps are SET 2a3’s at a couple of watts each channel? I quickly couldn’t find much except this made by a Don Garber http://www.6moons.com/audioreviews/jj2a3/hero_fi2.jpg I had a 3w Softone SET 2A3 from Japan (no longer made) he makes his own R-core transformers, amps ugly as sin but so cheap, This 3w amp drove a pair of monstrous Goldmund Apologue effortlessly. http://softone.a.la9.jp/english/ http://www.milliondollarstereos.com/pix100k/goldmund_apologue.jpg Cheers George |
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My system if a fi2A3, an Abbas DAC, and Klipsch Belle speakers so it seemed ideal for this type of attenuator. I was expecting it to be fairly neutral since not much is being added but I was stunned by how much improved the clarity of my system was. The quiet spaces in between the sounds are unbelievable. I am very happy with this new addition. |
Scott you could try 2 inexpensive different ways to power the Lightspeed Attenuator, that many say is an upgrade to the power pack that I use. 1: Pure dc, rechargeable Lithium battery these will last around 1-2 weeks of listening a couple of hours a day before a recharge is needed. Just make sure with the seller that it has a 2.1mm plug and centre is positive. http://www.ebay.com.au/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.X12v+Li-Ion+rechargeable.TRS0&_nkw=12v+Li-Ion+rechargeable&_sacat=0 2: Very good mains supply, also quite cheap. (9v-15v is fine) again make sure the plug is 2.1mm, centre positive. http://www.ab-system.hk/index.php?route=product/product&product_id=64 Cheers George |
Great clip George. Captures what they're like live. I figured I'd hear a difference with no bit stripping and the change in noise floor but I was really surprised by the spatial effect on the music. The soundstage is far wider and deeper. Very happy. As the Lowther's are so sensitive, I was really cutting a lot digitally. We rarely go over 50% on the Lightspeed (depends on music) and usually sit at about 1/3. Cheers, Scott |
Thanks very much for the great rap osmium, much appreciated. So nirvana has been achieved. The Romp by My Friend The Chocolate Cake, as one of our standard test tracks, was a special treat for our ears.Great Aussie talent, so much of it here, undiscovered. https://www.youtube.com/watch?v=We3HrsuqYJk When we added the Lightspeed attenuator the difference was obvious to us both. Digital volume control (from either the Touch or MiniDSP) was actually getting in the way and also raised the noise floor (as you would expect). Adding the Lightspeed gave us deeper bass, much wider soundstage, and transparency that finally took full advantage of the Lowther’s speed. Noise floor dropped into the black.Yes digital domain volume controls can be very good if near full up, they have to be used at or over 75%, this can be too loud for most systems. If under 75% they can actually reduce the digital resolution "Bit Stripping" to 14bit, 12bit, 10bit ect, and the lower you go, the less resolution you get. This is why the Lightspeed Attenuator being so transparent/dynamic is great, set the digital volume at full, adjust the Lightspeed Attenuator to the loudest you want to ever hear, and then use the digital volume remote to lower the level as needed, that way your never under 75% with it, this way you'll never "Bit Strip" Cheers George |
Hi George, I thought I'd share my quest for audio nirvana and how the Lightspeed was the final piece of the puzzle. Most of my setup is fairly standard gear - a Logitech Touch playing flac files over Cat6 cable from a Debian file server. Its optically connected to a MiniDSP 2x4 HD, which provides a flat freq response and acts as a DAC. Then a Cambridge Audio 651W power amp. The (less conventional) speakers are omnidirectional (from OmniAudio) with single Lowther DX4 drivers in each. My wife and I love the ominidirectional sound but we've never been fully satisfied with the sound in our house. The MiniDSP was a big help to fix room issues and the CA amp added the power and control but something was still missing. Or was something in the way? When we added the Lightspeed attenuator the difference was obvious to us both. Digital volume control (from either the Touch or MiniDSP) was actually getting in the way and also raised the noise floor (as you would expect). Adding the Lightspeed gave us deeper bass, much wider soundstage, and transparency that finally took full advantage of the Lowther's speed. Noise floor dropped into the black. We've been listening to the new setup over Xmas and we're both very impressed. My wife keeps telling me she is hearing new things in the music. I'm amazed it made such a difference to the soundstage and bass. So nirvana has been achieved. The Romp by My Friend The Chocolate Cake, as one of our standard test tracks, was a special treat for our ears. I'd also like to thank you George for your fabulous support and emails prior to getting the Lightspeed plugged in. I really appreciated it. Cheers Scott.. |
Hi Soundwise, once again thanks for the praise you’ve given on the Lightspeed. As it stands with me there’s not much that can make it sound better. Others here may give things they’ve tried. 1:Some say battery power, the best power you can give to the Lightspeed, then some (including me) say it’s virtually undetectable. you can try this using one of these rechargeable ones. http://www.ebay.com/sch/i.html?_odkw=12v+rechargable+Li-Ion&_osacat=0&_from=R40&_trksid=... 2: Some owners have replaced the gold rca’s with more expensive ones?? 3: As for the dual mono Lightspeed, 90% of owners that have both Lightspeeds (stereo and dual mono version), prefer the dual mono. I think maybe it’s because they can get perfect centre image due to system/room imbalances. As for the Vac vs the Cat JL2 maybe the Cat is just a better amp, the Vat being a tube should also be a great match but I can’t find anything (specs wise) on the VAC Musicblock 160’s Can you link us to anything (spec wise) on them, or can anyone else? Cheers George |
George, wondering if you have tried to upgrade the parts, if it is possible, and if so, can the sound get even better than it already is!? Noticed that the stage is wider, and that you can hear outer edges if that makes any sense. Also, does dual volume control do anything? I have tried your preamp with same type of audio note dac with Vac music block 160s…also with def tech bp 7002 speakers…not as good as the other setup , but not bad..I will use 1 ohm resisters to tame the tweeter output , but these speakers are 800 used and they sound holographic like the MBL radialstraters which cost as much as a large benz…. imho, bipolar is a far superior design compared to regular speakers.. best, I am looking forward to your next project! Soundwise |
Hi soundwise (Michael) you asked in a pm, What about he CAT output impedance any way to adjust that? Your Verity’s are an easy load for your Cat most of the time, but at 5khz there is a hard load of 4ohms in conjuction with around 50 degrees of negative phase angle. http://www.sonicflare.com/IMG_1966.jpg http://www.stereophile.com/content/verity-audio-sarastro-ii-loudspeaker-measurements#Xb47wFP2V0w59G7...But your Cat should be fine still at this frequency as well. As the Cat has only one speaker tap (no way to adjust the output impedance), but having a bit of negative feedback brings the output impedance low enough to handle this, and also there’s not much power needed at this frequency either. Quote: Cat JL2 http://www.soundbysinger.com/UserFiles/image/JL2%20Sig%20resize.jpg CircuitryI can see why your liking the sound of the Lightspeed in this very nice system you’ve put together. Remember the mil spec GE6550’s with the green label I mentioned a few posts back, they are a "cracker" of a tube. Cheers George |
soundwiseHi Michael, looked at your source and amp impedance's, and you have a nice impedance match. BTW: what speakers are you using, as the rest of your system looks very nice, though I'd hate to have to fork out for 12 x 6550's when time comes around. The ones I used to love were the military NOS G.E. green label ones, who's glass seemed twice as thick as anything else, and they cost over $200 each if you can find them new in box in Australia. Cheers George |
Glad to read the iFi iPower DC supply being discussed. I’m interested in using it in place of the as-supplied Auralic Aries Mini wall wart. I wouldn’t call my system extremely resolving, though I can easily hear changes in cabling. I could not, however, hear a benefit using the Audioquest Jitterbug. But, for $49 bucks from Music Direct and given their 60 day return policy it might be worth trying the iPower device. More likely to spend $49 as opposed $299 for the Auralic LPS. Am wondering if anyone other than mward has tried it. Tried searching discussions, this Lightspeed Attenuator thread was one of only two that came up. Thanks in advance for any input. |
Hey George, yeah the iFi just hasn't done much for my Lightspeed in my system. I feel like my system is resolving enough to pick out a bad recording pretty easily and to hear differences in cables, but I just couldn't spot the changes from this ultra quiet power supply if they exist. I almost felt like it made things a touch more reserved compared to the linear wall wart, but there is no way i could blind test prove it. That was probably pyschological negativity toward a change on my part. I like a lively system. I'm actually using the iFi right now and there is nothing wrong with it, just not a noticeable change for me. My system doesn't have super sensitive speakers or a room designed for extremely critical listening though. I would be interested to hear about the iFi from someone with a very revealing system and dedicated room. |
Hi mward, glad you like it, good that you gave it a few months before commenting on it. As for the " iFi 12v power supply "I think you are the first to try it, I had high hopes for this. But as you say it's not that discernible from the standard wall wart. Sam Tellig (Stereophile) and myself found the same, even with pure battery power vs the standard wall wart. You sensed there was something different but couldn't say what, and you had buckley's telling the difference in a blind A/B. PS: buckley's = Aussie slang for, "no way mate" Cheers George |
I’ve been using the Lightspeed for several months now. I purchased the dual volume control version to solve a balance problem in my room. It works great and is as transparent as advertised. I compared it to 2 other passive pre amps that I own, a Schiit Sys and a Tisbury passive. Swapping the 3 passives in and out, and running the source straight into the amp revealed that the 2 other pre’s altered the original sound ever so slightly. The Lightspeed sounds the same as the source going straight in. I still like the other 2 passives, but the Lightspeed won the transparency test. My Lightspeed is feeding a 47 kohm input impedance, no problems there. I really like the flexibility the dual volume controls give me, and the performance has lived up to what I have read about it. I’ve tried the iFi 12v power supply and a cheaper Jameco linear 12v supply. The difference wasn’t very noticeable in my system, but mileage may vary. I doubt I could tell them apart in a blind test. |
Hi simao, yes you can. Seeing the LSA Statement Intergrated has a "main in" this is the input you would use to put the Lightspeed's output into. What you are doing is bypassing all the Statement’s preamp section and using it just as a poweramp. Then you could use either dac you have to the input of the Lightspeed and use which sounds best with the Statement as a poweramp. Cheers George |
Thanks for bumping Glory, no not dead just resting. I’ve been on an extended holiday from any production runs, as they can be very taxing/monotonous to produce, just quad matching all the led/ldr’s can do ones head in, as to keep this kind of pricing I run basically a one man show. Got a few orders and half way through finishing off the next batch to go out. You should maybe get some more happy owners posting their thoughts if they are members of Audiogon and frequent these pages after they’ve had a good listen, but then most of the next batch is going to Europe and Asia, I don’t know how wide spread Audiogon forums go outside of the US. They seem to have their own go to forums in these areas. Cheers George |
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Yes, that 700cx Krell has low sensitivity as stated by Krell at
3.58 Vrms to give it full output just before clipping Most amps are usuall 1-2v. Your lucky the phono stage has so much output 8v (which I think is peak/peak anyway) not rms. Well even with 2v from your CDP's and you still get enough volume, all this speaks that you have no use for and active preamp/s with their even more gain and colourations. Cheers George |
Hi Georgelofi, I talked to Joe there at audio advisor, he said that the Vincent pho 700 does 8 volts max out put, your unit is passive?, I may put this on my modified krell 700cx to play with from time to time, it's 100kohms, however, it takes 3.35 volts to push, as you know, I've been pushing that amp with 2 volts running directly from the digital player, cheers |
audiolabyrinth Yes thought it was, saw you posting about it in other threads about it. A very nice looking phono stage for the money, looks like they really did some homework designing this. I found that it is 250ohms output impedance and it has 40db gain for the mm section and 60db gain for the MC section. This will be a great match with the Lightspeed Attenuator. As some of my customers have the Dynavector 75 which has the similar gain structure and they are over the moon with what they are now getting from their LP's using the Lightspeed with it. Cheers George |