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"Preamp" with remote (long)

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OK, it is now a "passive preamp" but that could change easily.

A while back (almost a year!?!) I purchased a pair of circuit boards from diyclub.biz to make a remote controlled preamp. The set consists of a board on which there is a 100K motorized Alps pot (4 ganged) and connectors for 12 VAC, LEDs, encoder, IR sensor and two sets of pins to connect it to the second board. The one thing it doesn't do is provide remote On/Off capabilities.

The second board has the relays that do the source switching. The set also comes with an IR remote. The purchaser must provide a 12 VAC transformer, all wires/jumpers and the LEDs.

Anyway, yesterday I got tired of having the boards sitting in the box and decided to put it into a case and make a passive pre. It took me most of the day but I finally finished it last night and have to say that I am impressed!

There is no hum or buzz in the output at all. When the unit is first turned on all sources are disconnected, the volume control turns all the way down and the LED for source 2 (?) blinks rapidly.

After several seconds source 2 is connected and the volume is automatically raised a small amount. Nice. Switching sources results in the same sequence- all sources disconnected, the new source LED blinks rapidly, volume control turned all the way down, new source connected (LED glows steadily), volume control raised slightly.

Pressing the mute button immediately mutes the source and then the volume control is turned all the way down and the source LED blinks rapidly. Raising the volume control "de-mutes" it.

You can also change sources using the supplied encoder, just turn the knob in either direction to cycle through the sources. Also the volume control can be turned manually if desired.

I put mine in a case I had laying around, it used to say 'Delco' on it so I assume it was from something automotive. I put some wood sides on it a couple years ago in anticipation of another project that never happened. It isn't great looking but it works like a charm. It would be easy to use the output after the volume control as the input to a "real" active preamp or to an integrated amp.

All told a very nice solution for someone looking for remote capabilities for not too much money (US $32 plus delivery).

DISCLAIMER:
I have no association with the vendor other than as a satisfied customer.

I'll post some pics later if anyone is interested in that part of it.
 
The Website seems to carry about as little detail as is legally permitted, it seems. :) How did you even make a choice before you plonked down your money?

The solid-aluminium remote handset option seems really attractive, for a fair bit of extra money.

Is this a passive volume control? Will their A15 preamp kit give me the buffer which I'd need at the output of the volume control?
 
The website is pretty thin on real info, however I emailed them and got a pretty quick response regarding the volume control. I also emailed asking for some hookup directions and they emailed me a couple of photos showing how to connect the two boards.

On the boards I got the volume control is simply a remotely controlled motorized 100K pot, no buffer. However the volume control could easily be used as the input to a buffer that you would build. I don't think the other set of boards has a buffer either, just a different set of input choices (four sources or a 5.1 source).

As for deciding, I figured the remote control motorized volume control alone would be worth the money and being able to switch four sources would be a bonus, so I just went for it.
 
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