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 |
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 |
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
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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 |
soundwise
endless power and dynamics and i have not even matched the
impedance between devices yet...
Hi 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 |
Hi soundwise (Michael) you asked in a pm, What about he CAT output impedance any way to adjust that?
MS
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 Circuitry
*Ultra-wide open loop in-circuit bandwidth of the output transformers enables operation of the amps closed loop response entirely within the open loop response, eliminating any requirement for the output stage to perform beyond its natural capability.
***Unprecedented stability into complex speaker loads.
I 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 |
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 |
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 |
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Genuine TDA1541R1
Best 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 |
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hopkinstk That’s an impressive list of gear you have there hopkinstk1: 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 |
toddverrone
One with a switch for different sources would be nice. 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 |
mickstuh
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). Hi 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 |
mickstuh
beone-audio.com
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)
http://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 |
tradeontheweb
esmith904
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 |
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 |
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If anyone gets the rechargeable Li-Ion battery pack, I'd be interested to know what difference/s you guys hear with it if you can post it up.
As It's getting harder and harder to find linear mains adaptors (smp's "switch modes" are taking over) and they make more noise.
I could be forced one day to supply these li-ion batteries with the Lightspeed instead of the linear supply.
Cheers George |
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ledoux1238
Does it come in a dual volume pot arrangement? Yes it does, it’s a $35 option, and is good for recording, room or system imbalances, also great for vinyl, as I never seen cartridges that have perfect channel balance. It’s all in the sales/pricing info I send in emails to customers, if you want it send me an email to georgehifi at optusnet dot com dot au Or if you have the skills, you can make your own at diyaudio forums, where I explain how to do it. https://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-passive-preamp.html Cheers George |
stray_cat
Now I just need to rig up a motor with remote control to control the volume knob externally with a belt. Has someone diy this before on anything? To go remote, you need the remote, a receiver, the motorised pot and power supply for it. You need a dual 100kohm Logerithmic pot, and this one is just that, you could use it in the Lightspeed. (no need to use the input board with the 6 relays, just the remote and motorised pot board with receiver) https://www.ebay.com/itm/New-LITE-MV04-Remote-preamp-board-Volume-Control-Input-Selector/11197635895... I won’t use them myself because the reliability factor is not there, and with supply is not there either for me over a long period of time, but there’s nothing stopping owners from doing it themselves. As for the used Lightspeed, I’ll PM the owner and see if it’s still for sale. Cheers George |
@chakster
You sent me a PM for info PDF's ect, but for some reason I can't return to you via Agon PM with my email address in the answer as this is the only way I can send you all the info. So you have to email me on georgehifi@optusnet.com.au.
Cheers George |
In the beggining of this thread @clipsal mentioned that First Watt B1 killed his Lightspeed Attenuator in terms of dynamics.
This could be true, in most systems the Lightspeed is a great match just like many tube pre's are, this could have been an instance where it or a tube pre's was not.
clio09
and the originator of this thread (rip)
pubul57
asked
clipsal
what were the other components, alas he was never to be seen/heard of again??? https://forum.audiogon.com/posts/75827Cheers George |
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hat i don’t like is even more limitation with Lightspeed to have just ONE input. It meant to be like that on purpose, because it eliminates the "source selector" switch which is another lightweight potential distortion causing contact taken out of the signal path. The Lightspeeds all about no contacts in the signal path. As you can see if you follow the green signal path, the music goes from input to output through nothing but a fixed resistor, unlike other preamps which have many contacts (that are very light in contact weight) that the signal has to go through. http://www.diyaudio.com/forums/attachments/analog-line-level/470539d1425885769-lightspeed-attenuator...A couple of customers use these external "source selectors switches" if they want to switch multiple sources and couldn’t be bothered changing over interconnects for non serious listening. That way they have the option of still hearing the best without it when they want or to impress their friends by going back to direct into the Lightspeed. with no source selector. The Goldpoint one is the better, it also seems it has the option of bypassing the source selector switch (see they know), BUT!! with what? another contact inside, so they take the nasty away but replace it with a not so nasty pin plug jumpers? http://www.goldpt.com/sw4.htmlhttps://cdn.shopify.com/s/files/1/0933/8332/products/51NDp9qHxUL._AA500_grande.jpegCheers George |
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roddek6
Non c est bien un des vôtres c est moi qui est rajouté une plaque de bois de chêne pour changer le look, le son est vraiment superbe
Bien à vous
Rodolphe OK I understand, each to his own for the look. I’m just glad it wasn’t another clone ripoff on the market, and even using the Lightspeed Attenuator front logo. Cheers George |
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One thing that I didn’t mention, was that xrl only sounds better than se over very long distances.
In many cases se actually sounds better, if an opamp was used to make the xlr circuit in your equipment, and you’d be very surprised to know just how many do it that way in many hiend products. .
Cheers George
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Thanks Mod's, one sic unit. |
brewmasterdon
Reading this makes me want to stick a finger down my throat.
There are probably some people after the first comment who might consider me a troll. If I continued making many comments over and over with no relevant experience to offer to the original poster’s question, I’m sure there would be more and more people who would think that I’m a troll Self confessed troll, you need to be banned. Maybe you should stick your active preamp down your throat instead, it probably fits. |
This thread has had 18 million views... that is nuts. Yeah Bruce, and the amount of PM’s are even more nutz to reply to.
Should have never sold it. They are the best preamp for the $ no doubt. It really does just get out of the way of the signal.
They pop up used sometimes for around $200-300usd there are over 950 units out there all over the world, just email me if you decide to get one of them for the correct wall wart for the US. And thanks for that rap! Or if your electronically minded, you could make your own, that I show how to do here. https://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-passive-preamp.htmlCheers George |
zeusodin
The LSA gives you the feeling that you are listening to the voice of God. The sound is so enjoyable so ethereal. The LSA simply gets out of the way of the music and passes on exactly what is on the recording.
Thanks for the great Lightspeed rap and kind words
zeusodin, if you want to experiment a little it's only a slight improvement over the linear regulated supply the Lightspeed has already to control all the LED's brightness. And that is to power them using this 12vdc CCTV Li-Ion rechargeable battery setup, cheap enough for the slight improvement. Just make sure with the seller that it's 12vdc and that the dc plug that goes into the Lightspeed is 2.1mm X 5.5mm and HAS to be positive centre. https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2540003.m570.l1313&_nkw=12v+cctv+lithium+...BTW all, I've halted all OS orders for a while as the last one took nearly 3mts to get to it's destination, the postal service all over the world is shot to hell, I'm also finding parts getting to me are taking twice as long. Cheers George |
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Yes you can use them, you’ll need
1 x Logerithmic dual 100kohm one for the stereo Lightspeed
2 x Logerithmic single 100kohm for the dual mono Lightspeed
to replace what you got. Also you can be in between clicks for image center? that can be a problem with 22 click pots
Cheer George
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Sorry clio, look a bit closer, only the positive passes through the pot/pots.
on either the dual mono or the stereo.
Sorry when I drew it out I was rushed a bit by the diy'er to post it up, and it not the clearest of schematics.
Cheers George |
First off clio, are you 100% sure the new ones you bought are 100kohm logarithmic and not 100ohm logarithmic or even linear??? @georgehifi, on a pot the middle tab is the wiper
Yes on the dual mono it is, and where the + of the power supply goes. But not on the stereo if you look at the circuit. With the original pots the Lightspeed never fully attenuated the sound, the pots in full counter clockwise positions still resulted in some low level sound coming from the speaker. I get the same result with the stepped attenuators, only the sound is much louder This is correct, all Lightspeeds Attenuators can never attenuate to absolute zero, as the LDR’s can never go to 0ohms, or complete open circuit I get the same result with the stepped attenuators, only the sound is much louder If all was wired up as the original/s were, the problem must be that the pots you bought are either not 100kohm, or not logarithmic but linear. If they are 100kohm and logarithmic, then the first step up in volume must be way to high. If I do move the switch clockwise the volume does increase, but not very dramatically. In full clockwise position the sound level is still reasonable.
If 100kohm value and log curve are correct ,this says to me you’ve wired it up wrong. The only thing I can suggest then to do is put back the original pots and see if it all goes back to normal, if not you’ve wired it up incorrectly Cheers George |
To all the "Lightspeeders" here at Audiogon and any new ones
OK, time to let all here know that Lightspeed Attenuator has been acquired by a most avid audiophile, and who will do it proud.
His name is Scott Campbell who also resides in Australia in the Sydney country side town of Green Point.
He’s been very committed hi-end audiophile for as long as I can remember. As for his component history I’ll let him tell you.
It was time to let it go after all these years, because it was starting to feel too much like “ground hog day” to me producing them.
He also won’t be doing any orders for the time being, because of the Covid outbreak here, and he will also need to setup his production premises.
His present email is Audio@tradeontheweb.net but no doubt will have another soon, more akin to Lightspeed Attenuator name in the future.
I will still be around for tech assistance, till he finds his feet.
Cheers, and a very big thanks for all your support George
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That's good news, glad you sought it out, hope that dicky amp didn't feed anything strong back into the ldr's in the Lightspeed, as the ldr's are in direct coupled contract with any amps input stage via the interconnect..
Cheers George |
The sources volume should be controlled up and down that’s all. (nothing added or subtracted)
The well known saying, "the best preamp should sound like a piece of wire" not adding or subtracting anything from the sound of the source, and if you don’t like it, you don’t like something else in the system, better to fix it.
The closest in order to "sounding like a piece of wire" and being "the best preamp", most transparent of all without colourations or distortions are:
1: Direct source to amp connection, if!! (the source has a digital domain volume control, and it’s not use below 75% of full, as not to "bit strip the music")
2: All passives (except tvc’s), if the system permits impedance compatibility (most do)
3: Active preamps + tvc's, which have colourations/distortions, (that’s why they all sound different), and may suit if finding the right one to mask the problems with source or system, but in doing so they ruin the transparency, and add colourations. (to me it’s better to fix the problems and have it all)
Cheers George
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There are some instances where additional gain is needed
Yes that needs to be added to No.2 " 2: All passives (except tvc’s), if the system permits impedance/gain compatibility (most do) Like our old friend pubul57 (Paul, RIP) who started this thread years ago Yes we all miss him dearly. Cheers George |
Don’t know what this clown 3 posts back hopes to achieve by copy/pasting exactly something I posted on a totally different thread about fuses, as the Lightspeed doesn’t even use fuses!!!!!!!!!!!. (there’s always one, probably a fuser)
But he managed to bump the thread which is good. Which created us to chat about the Lightspeed Attenuator and to give Scott (new owner) more exposure.
Cheers George
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tomic601
congrats on a great run George. Does the fng have plans for a remote ?
Yes Scott (new owner of Lightspeed Attenuator) in the future said he'll have remote, and maybe a more glitzy look. Something I always meant to get around too, but never did.
My proposed path; Herron phono pre >>>> Lightspeed >>>> RM-9
Should be a great setup as the Heron has ample switchable gains https://ibb.co/qYSnCLx for your vinyl. Cheers George |
