Lightspeed Attenuator a new passive preamp

[georgehifi]

You'll throw the impedance matching out the window if you use a voltage divider.
Best to lower the gain of the cdp or the amp. Via their feedback networks.
Cheers George

[wapo54001]

Originally Posted by georgehifi

You'll throw the impedance matching out the window if you use a voltage divider.
Best to lower the gain of the cdp or the amp. Via their feedback networks.
Cheers George

Hmm, on consideration, that probably applies to the single series resistor as well.

[LucasAdamson]

Has anybody successfully integrated one of these into their lightspeed attenuator?

Remote Control

I ask because I am hoping to integrate a remote control pot that does not affect the signal path purity, and a combination of this and the lightspeed would seem to be just that. The remote pot would control the Vdc of the leds, nothing more. The switcher is just by relays, controlled by some nasty non-audio grade electronics that is isolated from the signal path.

[udailey]

Hi Lucas
I think quite a few have used this. Skip the relay part for signal purity.

[georgehifi]

I friend ask me the same question and to maybe make it an opinal extra for my production Lightspeed Attenuator, I said my product is so reliable I have never had one back yet for repair or service out of hundreds around the planet, do you think it will stay that way if I put this into it?
For the indivdual to do it themselves it's fine so I said to him to get it for himself, and gave him some pointers below.
You need to make sure that the pot is log not lin, also you will have to do some surgical work to the pot board as it is meant to be a replacement for normal volume controls not the Lightspeed, as it works as you probally know totally different.
I wouldn't use the input swicthing board either as I have heard those relays in the siganal path compared to going direct. And the you will aslo need 12acv for this motor drive so you will need another wall wart. And last thing is how long will that remote last? and are they going to be available in the future?
Cheers George

[LucasAdamson]

Are you dismissing relay based input switchers in general or these in particular?

I ask because I have a much higher quality relay switcher, that uses 12v triggered relays that have gold plated silver connectors that mate perfectly, and keep the signal path much shorter than a rotary switcher, which has small and usually lousy alloy spring connectors.

I use several sources, primarily Vinyl, DAC and Tuner, so I need a switcher of some sort.

[georgehifi]

I have even tried what's considered the best, mercury based relays, and gold plated contact, they can all be heard to have a slight detriment compared to direct connection, as they are all a light pressure contact, unless you get some 50amp jobs they have stronger pressure contact but are huge in size and maybe not available in gold plate, and there are some silver contact ones, also but remember silver tarnishes very quickly.
Cheers George

[AndrewT]

The discussion here seems to be going along the line of
single direct input for best quality
or
multiple relay connected inputs at reduced quality
or
multiple switched inputs with longer wiring at reduced quality

It is very easy to make a decision in which camp one needs to be in.

[jonners]

Originally Posted by LucasAdamson

Has anybody successfully integrated one of these into their lightspeed attenuator?

Remote Control

I ask because I am hoping to integrate a remote control pot that does not affect the signal path purity, and a combination of this and the lightspeed would seem to be just that. The remote pot would control the Vdc of the leds, nothing more. The switcher is just by relays, controlled by some nasty non-audio grade electronics that is isolated from the signal path.

I'm using one of these with a udailey board and I'm very happy with it . I'm not using the input switching board. To use the control board you have to cut some earth traces on the pcb. Take a look here:Optical Volume Control Professional PCB

[LucasAdamson]

Originally Posted by jonners

Take a look here:Optical Volume Control Professional PCB

Great! Thanks for that! Just the link I needed.