the Poor Man 660 support thread

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thank you! Radiance
my psu is under test

few problem with q4(irf8040)  changed  with new one an now
my voltage are:  251v    135v  -17v  and slow start heater 6.3v
test just the psu  no load


hope it is ok
dingo.
 
yes! :)
have used some socket for all the transistor...so dont have to desolder...it is a good idea??

have just tested all voltages on psu with no load...
ordered some stuff ..tubes..socket tube  and big wima  for the other 2 boards

tomorrow will do other test and current  draw

will try to use the regulators outside the board for better dissipation attached isolated with a big piece
of alluminium heather !
 
It's been a while but I just wanted to stop back in a say that my Stereo PM670 is running great & is very useful... I really like what it does... it definitely has a "Flavor" but a cool one.

Does anybody know where to find the switches for the PM670?
(I think they were "uraltone" from China.)

I can't find them on ebay any more... I need 4 for a unit.

Thanks
 
Is anyone selling, or have a spare PSU TX, mine audibly hums even if nothing is connected to it, having some other PSU problems with the high voltage rails not working that i think the TX may have caused.

Unless of course humming power TX's are normal.....
 
kh  uraltones are stillavailable on ebay.not sure but i think shipping is cheaper on ebay(hong kong)  than from the european link above.
http://cgi.ebay.com/2P-24-Step-Attenuator-Volume-Control-Pot-Log-100K-Mono-/260636677626?pt=LH_DefaultDomain_0&hash=item3caf2815fa
you'll have to check for yourself

 
khstudio said:
It's been a while but I just wanted to stop back in a say that my Stereo PM670 is running great & is very useful... I really like what it does... it definitely has a "Flavor" but a cool one.

Does anybody know where to find the switches for the PM670?
(I think they were "uraltone" from China.)

I can't find them on ebay any more... I need 4 for a unit.

Thanks

Mine too !

I must say, that the 6n5p tubes changed completely my PM...after getting some nice matching, distortion levels lowered tremendously (compared to the unmatched 6bc8). And now, my PM is capable of taking quite high input levels without crying.

 
cool,
I never tried any different tubes in mine yet... I'm actually still using the "Single" tube in the side-chain.
(if you don't remember, I was the one that had problems with the sidechain tube & when I pulled one, all the voltages were perfect. It was thought that they may have been labeled wrong & may be the better versions of the tube... I forget all the fine details but anyway.)

I do get a little bit more color than I like sometimes & maybe someday I'll try some other tubes or mods.
 
Silvas said:
I must say, that the 6n5p tubes changed completely my PM...after getting some nice matching, distortion levels lowered tremendously (compared to the unmatched 6bc8). And now, my PM is capable of taking quite high input levels without crying.

Thing is, with those 6n5p's it's easier to find a matched pair (or close..), where as the 6bc8's are all over the place.
I think finding a matched pair of 6bc8's will give you the same (or even better if you read Kingston's post) results.
 
It's been a LONG time since I've been around here... if you have any direct links you can post, that would be cool.

Also, not sure if it's been discussed but is it possible to add a "Trimmer" to each tube stage to balance them out... like maybe on or in place of the Cathode resistor? ...this thought always crossed my mind. I know other VariMu's like the LCA2B I have has a lot of "Calibration Trimmers". I should try to dig up that schematic & see what's going on.
 
khstudio said:
It's been a LONG time since I've been around here... if you have any direct links you can post, that would be cool.

http://www.groupdiy.com/index.php?topic=28274.msg466613#msg466613

http://www.groupdiy.com/index.php?topic=28274.msg467006#msg467006
 
I finally tried the 6N5P sub (as suggested by Kingston) - and am very impressed by the improvement.

More overall gain (very welcome), more GR available and seems a little less push-it-hard distortion.
Will be keeping this substitution.   :)

----

I've been comparing the eguitar thru this unit (with a clean active DI) against my other diy tube pres with DI (to grid).

On eguitar, the Poorman just stomps all over them for character and general awesomeness, even without GR.
I have to hook it up to my hifi tube power amps and compare with some guitar amps.

So what is it about the poorman that makes it sound so good for eguitar?
Absence of negative feedback? Short, simple signal path? 6BC8 tubes? Edcor traffos?

All the above, I guess  8)

I think I will try a preamp using the same basic elements and explore it all some more. Along with the 6AS6.


 
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