PM670 Sounds like?

So I'm just finishing a few projects, and it is coming time to think about the next one! I've got a PM670 board set (which is partly stuffed), but I really would like to make a stereo pair of Drip's new 175. Who's loving their PM670? How does it sound?
Thanks!
Ian

iangomes said:

So I'm just finishing a few projects, and it is coming time to think about the next one! I've got a PM670 board set (which is partly stuffed), but I really would like to make a stereo pair of Drip's new 175. Who's loving their PM670? How does it sound?
Thanks!
Ian

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Where is the info on drips 175 ??

Rob Flinn said:

Where is the info on drips 175 ??

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Here: http://www.dripelectronics.com/175.html

Cheers!
G

Thanks G

yes, but what about the output transformer on the 175? 

pft, you guys are no help! haha
Drip went to sowter to custom make the tranny

To be perfectly honest Ian, I am not exactly in love with my PM670.

Mine is distorting far too much when compressing more than "a bit".
Its not a particularly pleasant distortion either.

Perhaps there is something wrong with my build. Maybe its my vu meter starving the plates of the 6bc8s. Maybe not.  :-\

Having said that, I compared the sound of my unit compressing bernbrues piano and his, and it was pretty much identical.

???

noulou said:

To be perfectly honest Ian, I am not exactly in love with my PM670.

Mine is distorting far too much when compressing more than "a bit".
Its not a particularly pleasant distortion either.

Perhaps there is something wrong with my build. Maybe its my vu meter starving the plates of the 6bc8s. Maybe not.  :-\

Having said that, I compared the sound of my unit compressing bernbrues piano and his, and it was pretty much identical.

???

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Hi,
the distortion, I initially had with the PM670 was caused by a scratchy pot and a loose wire at one of the transformers. The unit was still in beta testing phase at that time with wires flying all around. The early sample was only to give you a rough idea, how it sounds. Meanwhile I replaced the pots by rotary switches and fixed the wiring issue. The PM670 sounds amazing now. Don´t give up fixing the baby, it´s absolutely worthy.
regards
Bernd

lolo has some examples up at http://www.groupdiy.com/index.php?topic=32965.0

Not a trace of distortion, and that plain analag time constant network example is maybe even too smooth.

jeez, tough decision... thanks for the input guys... I may bail on this one. I have a d1176 on the way and I want to make a stereo pair of 175's... The boards are pretty much stuffed which is a shame (the white christmas ones too!), but that's the easy part. Getting the extra little bits, the trafos, the enclosure.... is the hard part. what to do... what to do!

iangomes said:

pft, you guys are no help! haha
Drip went to sowter to custom make the 175 tranny

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To make the interstage; not the output.  The output is the special one.  I see no mention about it at all, so what's he doing? 

http://www.dripelectronics.com/forum/viewtopic.php?f=10&t=141

yowza, that output tranny isn't cheap! 86 pounds!!!

http://www.sowter.co.uk/cgi-bin/sh000003.pl?REFPAGE=http%3a%2f%2fwww%2esowter%2eco%2euk%2facatalog%2fsearch%2ehtml&WD=8650e&PN=SOWTER_TRANSFORMERS_OUTPUT_TRANSFORMERS_12%2ehtml%23a501#a501

emrr said:

iangomes said:

pft, you guys are no help! haha
Drip went to sowter to custom make the 175 tranny

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To make the interstage; not the output.  The output is the special one.  I see no mention about it at all, so what's he doing? 

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Yes it is a special one.  It was used on quite a few UA tube stuff.  I have all the winding info and plan on having some made within the next few weeks to build up some "proper" 610 mic amps and a proto of a new comp.  If there was interest here, I'd have extras wound

me me me me me me me !!!! 

Okay, got it.  The 175 uses a less involved output transformer than the 176; thought they were the same. 

who are you getting to make them?

emrr, how is the output tranny less involved? jesus, with all of this talk about iron, I don't think i'll be able to afford to keep the pm670 boards! haha

emrr said:

Okay, got it.  The 175 uses a less involved output transformer than the 176; thought they were the same.   

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Yep.  I don't need the extra taps for what I'm doing at the moment but what I'll end up with will be good for 610's, 1008's and 175's so I'll be happy.

iangomes said:

who are you getting to make them?

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Whoever can do it correctly.  Not interested in cheap and cheerful, I'll pay whatever it takes within reason.  I need 10 so was going to order 12 

iangomes said:

emrr, how is the output tranny less involved?

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Jeez, look at it.  You want to buy one maybe, but you haven't looked at the schematics?

hey whoah I had not heard a 175 before until that drip demo. That's a beautiful unique compression character!

*makes a mark on todo list*

Wife still understands. barely. I wonder how long.