Phoenix Gold Phorum

I'm modding a Route 66 (M44 + M25) to a full 6 channel amp, with 6 inputs (normally 4). Therefore I need to transform the M25 pcb in the Route 66 into a real M25, with RCA inputs and gainstage etc.
I need a defect M25 (or a very cheap one ), or a sharp photo of the resistor/capacitors....
Thanks a lot!
Rob.

Here's a link to the mod if this is what you want to do.

http://download.phoenixphorum.com/Manua ... 66_Sub.pdf

Thanks, but i knew that one. The purpose of my mods is to make a 6ch fullrange with 6 inputs from the route 66. There are a lot of 6ch DSP's to drive this nice amp.
So I need a M25 and replace this for the M25 in the Route 66...

This is something like i wish to do. If only there was a way to just swap it out, but im sure the inputs and all the pots will not line up without drilling\filling holes. Too bad, i do have another M25 i could use for this.

LL

The original M25 pcb is exactly the same as the M25 part of the Route 66, but only the gainstage potmeter, RCA sockets and all the caps/resistors/opamps are not mounted on the pcb. So you only heave to drill three holes...
If someone knows a M25 for sale, please PM.

After looking closer, i see what you are saying. Im not sure why but i always assumed the m25 was on the right side. Its not, lol. so ya, 2 holes for pots, 2 more for RCA inputs and its a 6 channel. The only thing missing would be the output RCAs for the m44. No big deal.

My only issue with it is modding a SE amp. I will have to think on it. But thanks for giving me a solution to a problem i have been thinking about for a few weeks.

LL

Today i did succeed in analyse (and draw) the inputcircuit of the M25, just a single gainstage and bypass the useless bassboost section, tbc...

So you are going to add a pair of rca's and a potentiometer for the gain?

Someone sell this man an M25 so he can perform this mod, lol. I guess this stuff is a little harder to find over where you are. I keep an eye on the local buy and sell and seem to find quite a bit of PG stuff. I just bought another M50, not because i need it, but just because he was 3 blocks away and i talked him down to $40.

Good luck, although it sounds like you have it pretty well figured out. Post lots of pics when you get it finished.

LL

I'm going to replace the gainpot from the M44 sub-part to the M25, and add the components needed for the gain pre-amp (opamp, resistors, caps, rca sockets). Only adding a gainpotmeter and the rca sockets is not enough...
There are some very good M25 for sale overhere, but way too expensive for this purpose ($120,00 i think..)

I got a m25, do you need close up pics? I would sell mine but for no less than 80 bucks (got brand spanking new caps, burr brown opamps).

This afternoon I succeed in putting all the parts on the pcb and it's working! Opamps are the National LME49720, I allways use this one when possible, very low distorsion, nice sound. But Burr Brown OPA2134 or Philips NE5532 are very nice...
Also did a mod on the input sensitivity, 0,2-2V range is a bit low today. I have to tweak it a little more to get 4V.

Some pics:
new caps:

Empty pcb:

PCB with some new parts...