Apology required from me given subsequent explanation.
Saw initial post and was irked by it.
My mistake.
Sorry.
Location: London
Posts: 25
I'm Richard.
Apology required from me given subsequent explanation.
Saw initial post and was irked by it.
My mistake.
Sorry.
Go for the best: https://www.cw-industrialgroup.com/P...entiometer-RCP. They are fitted in the preamps I use.
Barry
Location: North Island New Zealand
Posts: 1,757
I'm Chris.
Location: scotland
Posts: 330
I'm alan.
Now that as Spock would say...is Ilogical captain !!!
Location: North Island New Zealand
Posts: 1,757
I'm Chris.
Yet it is the simplest in terms of audio path being preserved, and at the same time being a variable attenuator and a switch for inputs in its Off state
LDR are proven to add distortion
Simplest isn't the key.
Lowest distortion is where the OP should be aiming.
Location: North Island New Zealand
Posts: 1,757
I'm Chris.
And lowest distortion is with a good LDR circuit.
LDR's simply reflect back how good or poorly the anode and cathode are driven, do that well and distortion
disappears, however do that poorly and figures and graphs you are poised to paste, are what results.
What does it take to drive the anode and cathode correctly, is what you need to ask. You also need to ask
yourself why graphs of distortion are not provided with potentiometers passing audio signals ?
https://pinkfishmedia.net/forum/thre...tortion.68076/
Last edited by Light Dependant Resistor; 12-06-2019 at 22:16.
Alps and the like do add a modicum of distortion, which is why I moved to Stepped Attenuators.
There is a forum that offers free measurements of HiFi equipment. Why not send them one of your preamps for testing? I'll try and find a link.
Have your Stereo Coffee preamps been tested already?
I am afraid independent testing with published measurements consistently support the claim that LDR's drift over time and add distortion.
Location: North Island New Zealand
Posts: 1,757
I'm Chris.
I think you are referring to Audio Science Review - I am nearly ready to send Amir a cased unit to review.
I too thought stepped attenuators were good, which was in 1992 hearing them with Vishay bulk foil resistors
Just as Rob expresses here in the last paragraph https://robmid42.wixsite.com/diyaudi...ich-ldr-preamp
stepped attenuators are not very high on the list, when compared to LDR's
Both of your presumptions, expressed as fear, are wrong.... which time will prove. There should be a review
at Pink Fish forum in about 3 weeks, sorting through what sounds best.