Lightspeed Attenuator a new passive preamp

[Terry Demol]

Originally posted by georgehifi
chewrock, mine are'nt the Perkinelmer ones, mine are from a different company, also I told you they have been on now for 2 years 24/7, are you deaf?, not just mine but all of my customers, and all are as good now as the day they were built. As for the Perkinelmer VTL5C3 lasting only 41 days, you are scare mongering, if you use them as I have outlined, the life should be as long as my units, which so far is 17500 hrs and still going strong.
As for all your negative comments, it's bizzare that someone thinks they can give ANY constructive input when they have not even listened to or built one, and who admits they listen to oxidized pots that are over 20 years old.

Hey George,

Please relax, most of us are enjoying this thread immensly and are
thankful for your input.

WRT the life expectancy have you had these on 24/7?

Thanks

Terry

[georgehifi]

Originally posted by Terry Demol


Hey George,

Please relax, most of us are enjoying this thread immensly and are
thankful for your input.

WRT the life expectancy have you had these on 24/7?

Thanks

Terry

Sorry Terry, but I have a short fuse sometimes.
You asked in your PM to me.

[Private mail quote removed by moderator]

Ok, time to shoot oneself in the foot, the company I deal with is Silonex of Canada the units I use are the NSL-32SRS (sorted)
There is no published life expectancy on the units I am using, therefore I presume they could be indefinite.
I have had no degradation after 2 years of being on continuously, but mind you that the unit is left at the half volume position (normal listening), this is only half led power, this could be different if it is left at minimum or maximum when the leds are at full power, I have not tested it in these two positions for any length of time, maybe a day or two with no problems. The leds themselves would then have a certain life expectancy, how long I have no idea, could be years also. So far there has been not one failure in any of the units I have made.

Cheers George

[Badge]

George,
Thank you so much for the information you have shared here. I have a question. The photo of your commercial offering only has one volume control. I thought the design required two, two gang pots? Are you using a single four channel potentiometer?

[georgehifi]

Originally posted by Badge
George,
Thank you so much for the information you have shared here. I have a question. The photo of your commercial offering only has one volume control. I thought the design required two, two gang pots? Are you using a single four channel potentiometer?

Badge, if you look at the ruff circuit that I posted, it has one dual that can be 100k log or linear. You can use two duals one for each channel that would give you balance between channels, you could also de-adjust the 1k 25 turn trimpot to give you small range balance control, which is what I do, but it's only a couple of db each way.

Cheers George

[Audionutz]

I've been following this thread with interest and thought it might be time to add my 2 cents worth.

Firstly, I am not affiliated or related to the builder of the Lightspeed Attenuator, but I do own one and am a confirmed believer in its sonic superiority.

My path towards this unit has been long and varied. My system consists mainly of a pair of Infinity RS4.5's coupled to an Audio Research D250. Sources have varied over the years, but currently they are a Marantz CD17 KI and a Micromega Duo Dac. I would say this system is extremely musical but revealing - I'm into the music, not the equipment. I care more about how it sounds than how shiny it is or how many LED's I can see.

In terms of preamps, those that have passed through are as follows, as near as I can remember, but probably more; Phase Linear 4000, Bryston BP25, Dynaco Pat 5 and Pas 3 (modded), McCormac Micro Line Drive, Whatmough Passive, NAD 1100 (modded), Kenwood KC-1, Accuphase E-202, AV Light Surround Amp/Processor/Preamp, Pioneer Spec 1, Avantic etc etc

I by no means claim anything approaching "Golden Ear" status, but I do know what I like to hear and I believe I can recognise it when I hear it.

A friend recommended the Lightspeed after an afternoon of listening to his system. I liked what he was trying to achieve in terms of a true "Holographic" sound, using some rare Q-Sound Albums as a benchmark. The resulting improvements with "normal" tracks, once the system was tuned to the Q-Sound, were impressive indeed. Anyway, he mentioned the Lightspeed as a Preamp worth investigating. Following several long discussions with the builder, I placed my order. At approx. $550 AUD, it was and still is, an absolute no brainer.

I have now been using it for over 2 months, long enough to form an opinion, I believe and long enough to assess its merits. The sound is neutral in the extreme and if there are any enhancements or coloration at all, they are in the area of sound field extension and depth, but not at the expense of clarity and "musicality", if I can insert such an 'oft used and abused term here. One mans musicality may well be another’s ear bleed in my experience. Suffice to say that I like to hear everything that was recorded, I like to hear all the detail present, but not thrust at me so that it overpowers the "feel" of the recording. Basically, like a large majority I suspect, I like to have my cake and eat it too - a "system for all seasons" if you will.

The Lightspeed distinguished itself within 10 minutes of connection. I wont say I was awe-struck, or bowled over, or any of the usual Audio Superlatives that seem to fly thick and fast when a change for the better is heard in someone’s system. I guess the most noticeable thing for me was that the whole system sounded much more coherent, placement of both vocals and instruments were impeccable, with a true widening and deepening of the soundstage. Yes, I did hear things on some of my reference discs that I had not noticed before at a lower listening level than previously, always a good sign in my opinion. Bass was slightly sharper, especially in the leading edge of percussion instruments, which is apparently a Lightspeed trademark. Vocals, especially female, were presented with a silky lushness (Sorry for the superlative, it snuck in on me!) that let me hear all the sibilants along with each intake of breath from Norah Jones. Decay was excellent, with piano especially, hanging after being struck and then wisping away into a lovely black space between the sounds.

As you can probably guess, I like my Lightspeed, I like it a lot. Quite simply, it's wiped the floor with everything I've heard to date in my system. I now discover that it is being used in systems that cost considerably more than my first house, and is being used regularly and happily. Not that this means much to me, but it's nice to be in such illustrious company, if only by proxy!

To those who doubt its credentials, based on whatever notions of theory or practice they may have, all I can say is this: Don’t criticise until you've tried it and at the current price, you'd be crazy not to give it a go!

[georgehifi]

Thanks for the glowing recomendation Audionutz, It's the type of explanation to the sound I would have liked to have posted, except it sounds a bit biased coming from the designer, so I had to temper my thoughts.
I hope that this will give some of the DIY'ers on this forum the confidence to build one for themselves, as I also beleive that it sounds very special, to the point of saying to one self that all other devices active or passive sound flawed in some way when listening to one, it's instantly reconizable.
The parts/nice case should be around the $150-$200aus mark and about a day to build, also I double regulate, down to 12v first then again regulate to 5v for the led power supply, it's important to get the this supply super smooth and stable and isolated as much as possible. A scope and sigal generator is handy to do the calibration 100%, though it can be done close enough by ear. Happy building.

Cheers George

[wboyd]

Very interesting thread...I have been following it from the beginning.

Hey George...any chance we could get a teaser shot of the inside? You know how us DIY'ers love our audio porn!!

Thanks,

Wayne

[TimA]

Audionutz,

Interesting! Can you please clarify - are you using the attenuator as a passive volume control or is it part of an active preamp, and/or did you insert it directly in place of an existing attenuator within an existing circuit, if so what was the original attenuator? Many thanks.

Tim.

[Audionutz]

Originally posted by TimA
Audionutz,

Interesting! Can you please clarify - are you using the attenuator as a passive volume control or is it part of an active preamp, and/or did you insert it directly in place of an existing attenuator within an existing circuit, if so what was the original attenuator? Many thanks.

Tim.

TimA,

The Lightspeed is being used purely as a preamp, between the Micromega Duo DAC and the AR D250 amp. Im only using the one source on this system at present and the Lightspeed gives a single input and output, plus has more than enough volume range for my setup.

[georgehifi]

Originally posted by wboyd
Very interesting thread...I have been following it from the beginning.

Hey George...any chance we could get a teaser shot of the inside? You know how us DIY'ers love our audio porn!!

Thanks,

Wayne

I would Wayne, but the ones that are made for customers, all have potted circuitry, therefore you can'nt see anything but cubes of of potting mix.
What I can do the next time I have it open is take photos of my own prototype one which is not potted, though it's not as neat on the eye as the others and the case is ordinary, but you'll get the drift of the layout.

Cheers George