the Poor Man 660 support thread

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Well, I did not know he had low end issues. Indeed plenty of comments and that makes sense.
Still there are some people who don't comment on this, but like you said, none of us know the "Standards" others go by or what they consider good or normal sounding".

I'm still building mine. This is probably the longest build for me so far. I have pretty much soldered everything except for the last two rotaries which I hope to finish next weekend.
Then I'll wire things up and hope it works. I have no spare tubes so no matching the first time. If it sounds really horrible I'll order some more. Richard from Leeds in NY told me he sells matched pairs.
 
I actually got some time the past couple of days to give this thing a good listen.  Since I'm basically hooking it to the patchbay in my Neotek, which is unbalanced, I had to make few special cables to do the connection right.  Once I did that, I tried the compressor again on numerous sources.  Some observations:

1.)  When I turn the threshold control on the right channel to zero, both meters move down and come to rest like the unit is compressing a bit even though there is no signal present.  The happens whether or not the stereo link is in "dual mono" or "stereo."  As soon as I click the right threshold to 1 all systems seem normal again.  I've had a look at the circuit and the resistors on my controls (the right and left are identical as far as the resistors go) and I can't see any errors there.  Has anyone else seen this issue?

2.)  The unit takes quite a while to warm up and settle down.  Much longer than any other tube gear I've had.  I'm pretty sure it's the nature of the beast for this kind of comp, but letting it warm up for an hour or so really does make a difference in the way it behaves.  

3.)  Before I got the proper patch cords made, I, too, noticed a drop in bass when switching between bypass and compression.  Once I got those connections sorted, I can't say that I hear much loss now at all, but I need to do some more careful volume-matched listening to make sure.  It's definitely not as noticeable as it was and if it's still dropping a bit of bass it's much harder to tell now.

4.)  This thing will heat a small room.  I have two small fans moving air through the chassis where the power supply is and they're too noisy, so I'm going to get one larger fan and run it at a slower speed to help with this issue.  I made an adjustable DC fan supply so I can control the fan's speed.

5.)  I could use this on the mix buss (hitting it SOFTLY) but I'm not sure I'll ever find a need for the color it imparts because I mainly record jazz and classical.  It might be just the ticket on some grungy rock stuff!

6.)  It works fine on individual instruments and I'm starting to like it quite a bit as a dual-mono compressor.  I like what it does to upright bass for sure.

7.)  I just bought a stock of tubes (both types) for this beast and will try to match the pairs as close as possible and give that a go.

I plan to implement Kevin's (via Bluebird) time-constant mods to get some faster times.

All in all, it's a complex beast and I think once we get more feedback from other builders we'll ultimately have an even better compressor than we have now.  I would have liked to see analag check in more on this thread and comment about some of the issues we seem to have in common, but I understand that he's been super busy and doesn't have the time right now.  I completely understand this as I've been pretty much up to my ears with my day gig since Sept. as well.  When he gets some time, though, I'd love to hear his comments because I always learn a lot from reading his thoughts.

Cheers,
--
Don
 
Hi,

I was just wondering what the total cost of the parts is for a stereo unit built and ordered in germany.

Thanks and Regards
Ray
 
Also wondering where to get the 2X24 rotary switches. I've spent HOURS searching for elma ones. Can't find them ANYWHERE except on goldpt.com and thats with resistors installed.. and the ones that arent are around 100 each which seems a bit steep (i seem to remember someone saying they go for around $50 each)

So any help there would be great. Also the resistor values for the switches are in this thread aren't they.
 
TheGuitarist said:
Also wondering where to get the 2X24 rotary switches. I've spent HOURS searching for elma ones. Can't find them ANYWHERE except on goldpt.com and thats with resistors installed.. and the ones that arent are around 100 each which seems a bit steep (i seem to remember someone saying they go for around $50 each)

Did you contact Elma?
http://www.elma.com/StaticPages/Common/English/About/wwa/CountryAustralia.html


TheGuitarist said:
Also the resistor values for the switches are in this thread aren't they.

Yes, values are somewhere in this thread. See first page for directions ...click on "rotary switches"
 
TheGuitarist said:
Also wondering where to get the 2X24 rotary switches. I've spent HOURS searching for elma ones. Can't find them ANYWHERE except on goldpt.com and thats with resistors installed.. and the ones that arent are around 100 each which seems a bit steep (i seem to remember someone saying they go for around $50 each)

So any help there would be great. Also the resistor values for the switches are in this thread aren't they.

Try to find the cheaper ones on ebay... they're Blue & White & I think made in china but work great & cost about $10 each.
Someone on the forum recommended them & posted a link.
 
I got my elma straight from them, just over $50 a switch.

Can someone smarter than myself confirm my rotary switch diagram?
index.php
 
benlindell said:
I got my elma straight from them, just over $50 a switch.

Can someone smarter than myself confirm my rotary switch diagram?
index.php

sorry for the delay, and I just had a very quick chance to have a look.
BUT:
(to Transformer and PCB)
there is nowhere a connection from any switch to the transformer and the PCB.
 
Ah yes, my eyes got confused I see 1 only goes to the pcb, so I assume I got everything else correct, thanks for looking.

Kingston said:
[silent:arts] said:
where is deck 2 reversed in the wiring guide ???
I just rechecked and can't find a mistake ...

OK not necessarily a mistake, but just a thing to keep in mind. Especially for tapped attenuator, both decks should be soldered so that the resistor banks are equal, both decks having same resistor values at same positions. That means deck two end point wires will be reversed compared to the guide.

Create two opposite direction resistor banks (like the guide assumes), and trouble shooting will become a real bitch for tapped attenuators.

The main point still is that the wiring guide ONLY works for full range attenuators, which is not what I believe most people are using.

This is the post that got me really confused since I'd like to use the tapped attenuator instead of full range.
 
sorry about that. Just look at the original schematic, especially the numbers 1,2,3 showing the orientation of the pots. then just wire your resistor banks "as pots", keeping in mind the tap points. Not even the wiring guide is a clear as that.

It's very difficult to explain it in words. I already failed once.
 
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