When making a DIY preamp there should be some kind of volume control. There are many possibilities like a normal Alps, Stepped attenuators (Serial, Shunt), Reed relay based and probably many others.
It seems Pass Labs use some kind of advanced electronic controlled volume control?
Is that still the case?
Is it something that can be adapted to e.g. a BA-3 preamp?
Maybe a simple version of it (I don't need remote control)?
Is there some detailed information of how it is made?
Is the choice of volume control "over hyped" in highend pre-amps?
https://www.passlabs.com/sites/default/files/x2.5_om.pdf
"The electronic volume control allows greater than 60 dB range and is driven by a micro-controller that reads the optical encoder serving as a front panel volume control. In this manner tracking of the volume of the two balanced channels is possible with accuracy unavailable on any ordinary volume control, assuring precise level steps and high common mode rejection in balanced circuits. Wayne Colburn’s exceptional volume control in conjunction with the fluorescent display give the user ability to replicate volume levels with absolute accuracy in steps of roughly 3dB."
It seems Pass Labs use some kind of advanced electronic controlled volume control?
Is that still the case?
Is it something that can be adapted to e.g. a BA-3 preamp?
Maybe a simple version of it (I don't need remote control)?
Is there some detailed information of how it is made?
Is the choice of volume control "over hyped" in highend pre-amps?
https://www.passlabs.com/sites/default/files/x2.5_om.pdf
"The electronic volume control allows greater than 60 dB range and is driven by a micro-controller that reads the optical encoder serving as a front panel volume control. In this manner tracking of the volume of the two balanced channels is possible with accuracy unavailable on any ordinary volume control, assuring precise level steps and high common mode rejection in balanced circuits. Wayne Colburn’s exceptional volume control in conjunction with the fluorescent display give the user ability to replicate volume levels with absolute accuracy in steps of roughly 3dB."
and the Maxim - so cheap you can blow up one per day before you get it right.
That's the one I'm going for
http://www.diyaudio.com/forums/anal...s-72320-electronic-volume-40.html#post5490862
That's the one I'm going for
http://www.diyaudio.com/forums/anal...s-72320-electronic-volume-40.html#post5490862
Picture more like a relay step attenuator, except everything is on a chip. It has advantages (size, cost, no mechanicals, zero cross detection for QUIET SWITCHING) and disadvantages (no control over the resistors quality/properities). Also - probably not suitable for after the preamp (like A-P or Bosoz) but for before as is more customary.
You need some sort of micro-controller with the relay or the chip, regardless of how the human interface is, but once you are that far - you can do anything you want. It's a learning curve, and I'm at the start of it
Personally - the ONLY remote control that I require is volume.
You need some sort of micro-controller with the relay or the chip, regardless of how the human interface is, but once you are that far - you can do anything you want. It's a learning curve, and I'm at the start of it
Personally - the ONLY remote control that I require is volume.
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Ok......I can live without remote on volume…...but it is nice to have. But if I can get better quality using an Elma based stepped attenuator I will go for that. It seems if you make a high-end product as a manufacturer a remote volumen control is mandatory as people who buy a preamp that cost +20k USD expects a remote controlled volumen. If it is also cheaper to implement…...it is a "win-win".
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