A twisted tale about a logarithmic relay attenuator

[SheldonD]

Russ I can see where this could/might apply to more than 2 channel stereo
say 5, 6 or 7 would iit be possible/feasible to incorporate a sort of preset to each channel? i.e. boost or attenuate each channel independently of overall loudness?.

This would ideally be done through software in your programamable modules.

I realize this is an order of magnitude leap ahead of what you just proposed.

[moamps]

Originally posted by SheldonD
[B]Russ I can see where this could/might apply to more than 2 channel stereo
say 5, 6 or 7 would iit be possible/feasible to incorporate a sort of preset to each channel?

... and the balance feature.

[SheldonD]

Yes,
essentially what i asked about is a balance function across channels not jsut stereo.

[apassgear]

Excellent approach Russ, I like the idea of a simple attenuator.

I would suggest too keep it as simple as possible as you have. As soon as you start adding functions and complexity to the circuit some of us (me included) will shy away from building it.

I guess many on the forum are not digital inclined and have never programmed a PIC (me included once again). So what are the alternatives for those of us at the digital end?

[Zen Mod]

Originally posted by apassgear

I guess many on the forum are not digital inclined and have never programmed a PIC (me included once again). So what are the alternatives for those of us at the digital end?

buy it as a kit?

[Russ White]

Originally posted by SheldonD
Russ I can see where this could/might apply to more than 2 channel stereo
say 5, 6 or 7 would iit be possible/feasible to incorporate a sort of preset to each channel? i.e. boost or attenuate each channel independently of overall loudness?.

This would ideally be done through software in your programamable modules.

I realize this is an order of magnitude leap ahead of what you just proposed.

Hi Sheldon,

Certainly, there are a host of things anyone so inclined could do with a controller in the firmware. I will explore some ideas later on in the thread and probably supply some code and layouts to help people out.

Cheers!
Russ

[Russ White]

Originally posted by apassgear
Excellent approach Russ, I like the idea of a simple attenuator.

I guess many on the forum are not digital inclined and have never programmed a PIC (me included once again). So what are the alternatives for those of us at the digital end?

Thanks Tony, Coming from you that means a lot to me.

I am still in many ways just a beginner here, so having some little bit of success here really makes me feel great.

As for the PIC programming I am going to be posting a layout for a simple serial port programmer I did which is based on the "RCD" PIC programmer. Very simple to use with open source free software. Once you have that and the HEX code all you need are the PICs to program.

Alternatively, as Choky said Brian and I may well decide to sell some of these as kits. Have not made any hard fast decissions yet.

Cheers!
Russ

[Byrd]

Hey Russ - Looks good. Advantages over the Kooka - which by the way sounds absolutly transparent to my ears.

NUdge Nudge, Wink Wink * This almost seems like it could pretty easily be converted into a source selector - and extending it to include an LCD display shouldn't be to far off

[mpmarino]

Oh Russ, I knew you could do it! Nice work and an answer that a LOT of peeps are looking for.

Hmm, I wonder if my WILLEM programmer can program that pic thingy...it's not listed. but others like it are... Any idea? I've only used it for eproms to make ellicit DVD players

later...

[promitheus]

The attenuator looks great.
The pads and holes though for the resistors look a bit small.
Bigger pads are easier to solder.
Will the pcbs be double sided with vias or single sided?
It looks like single sided to me so maybe larger pads are a good idea.
Using the DAC with the a normal pot is also a good idea because there is know need for a display.
I also like the idea of a 7bit control because its more stable and not so many steps. 6 would also would be ok.

The relays are very good. I think one could also use others but I am not so sure how universal they are.

If the input selection is also so simple and good I will be surely using them.
A mute Relay would be helpful to make a time delay on turn on etc.