That certainly is a conclusion. For me, although I don't like distortion and try to design circuits that are as linear as possible, its elimination is not my top priority, if some other more worthy quality can be gained, perceived or imaginary. Over time I find that annoyances and imaginary improvements usually become more apparent, can one live with the compromise? I have been using valve amps for the last 10 years.....
Jan I can't see that in the datasheet.
https://html.alldatasheet.com/html-pdf/1122437/LUNA/NSL-32SR2S/114/1/NSL-32SR2S.html
https://html.alldatasheet.com/html-pdf/1122438/LUNA/NSL-32SR3/113/1/NSL-32SR3.html
The only curve I see is the LED current VS the LDR resistance which relation is very non-linear but is not the one affecting the signal through the LDR alone as it is set to a fixed value, ie. listening volume.
I am just curious to understand what kind of distortion is it, VDR? From the datasheet it seems to have some tempco, yes, but I will assume it's a rather slow acting thermal phenomenon not affecting most of the audio band.
Agree hbc I have myself a tiny tube amp, I used to listen to it for years and never got tired of it, it had a certain sound signature that stood out from ss amps I have ever had access to, I am aware it's a matter of a subjective feeling, and with regards to LDR's and Lightspeed alike attenuators and their level of distortion, they are probably ok too as long as one is aware of both the subjective and objective qualities, I was just surprised how high the distortion can be in these components.
btw I found an old post, #1007 & #1008 in the Lightspeed thread with distortion measurements for
Series LDR & Shunt LDR VS Series Resistor & Shunt LDR
https://www.diyaudio.com/community/...uator-a-new-passive-preamp.80194/post-1391642
That thread is just too massive to search through.. anyways, interesting to learn more about the LDR's for audio.
Distortion that I can't hear isn't a problem. Its all about the ears!
LDR volume attenuators sound cleaner to me than Goldpoint or Schiit Saga stepped resistors, Noble or Alps pots, and even a TVC Promethius I owned for awhile.
I am open to any volume attenuator that sounds cleaner than an LDR but doesn't cost crazy money.
LDR volume attenuators sound cleaner to me than Goldpoint or Schiit Saga stepped resistors, Noble or Alps pots, and even a TVC Promethius I owned for awhile.
I am open to any volume attenuator that sounds cleaner than an LDR but doesn't cost crazy money.
Very good point, once the 'volume' is set, you're set at one point on the curve, and that curve non-linearity should not affect the signal.
Thanks for educating me ;-)
I do remember from my projects that a signal level above a few 10's of mV was distorted up to 1% or so, so the question now is what causes it. Maybe it is voltage dependent resistance, I don't know.
I'll research it further, and let us know if you find any more info as well.
Jan
Thanks for educating me ;-)
I do remember from my projects that a signal level above a few 10's of mV was distorted up to 1% or so, so the question now is what causes it. Maybe it is voltage dependent resistance, I don't know.
I'll research it further, and let us know if you find any more info as well.
Jan
hah, alright then, in the meantime I will have a closer look at PGA2311, MUSES72323 etc for audio applications.
:)
I've had excellent results with the Cirrus CS33xx series. I used the 8-channel version in a 3-way stereo level control with individual level tuning and common balance control. https://linearaudio.nl/dcx2496-active-output-mod-6-channel-vol-control
You need a micro to control it all, but I guess the same would be true for the types you mentioned.
This is the stereo version: https://www.mouser.be/datasheet/2/76/CS3310_F1-1141873.pdf
8-channel version: https://www.mouser.be/datasheet/2/76/CS3318_F1-1142113.pdf
Jan
Last edited:
Since I have a LDR and some buffers around, I'm drawn to reproducing the approach of this device. I've seen references to a version that uses a step-up transformer to add 6dB gain, which can be useful in some systems. Does anyone know what transformer is used in this version of The Truth?
Thanks in advance,
Pete
Thanks in advance,
Pete
Anyone worth his salt characterizes an active audio component and operates it the best possible way. Series-Shunt LDRs cancels 2nd harmonic at 6dB attenuation and you see that as the big dip in distortion estimated at almost -98dB...who wouldn't want that?!
The transformer is something Arthur Salvatore found.
I used a TRUTH for a few months and found it is firmly in the IT WORKS category of audio components. It is a clever idea and it works. I found it had many downsides and after playing with it and getting nowhere it lays in pieces around the house.
I substituted the BUF for a Pass Toshiba buffer and it still was not satisfying. Those photocells are not as quiet as a regular resistor.
If one wants to use a transformer VC - Zen Mod has one he offers with buffers. I have not tried it but it has many happy owners.
I used Dave Slagle's TVCs and never found them to suit me.
But the TRUTH must work wonders for Mr. Salvatore. I believed his breathless prose.
Ed is quite a likable character and he has owned lots of cars. None of any special merit ...
I used a TRUTH for a few months and found it is firmly in the IT WORKS category of audio components. It is a clever idea and it works. I found it had many downsides and after playing with it and getting nowhere it lays in pieces around the house.
I substituted the BUF for a Pass Toshiba buffer and it still was not satisfying. Those photocells are not as quiet as a regular resistor.
If one wants to use a transformer VC - Zen Mod has one he offers with buffers. I have not tried it but it has many happy owners.
I used Dave Slagle's TVCs and never found them to suit me.
But the TRUTH must work wonders for Mr. Salvatore. I believed his breathless prose.
Ed is quite a likable character and he has owned lots of cars. None of any special merit ...