New to me paraglow monoblocks

[Doc B]

The main practical difference between a soft start and the manual switch is the soft start resets itself vs. you have to remember to turn off the switch each time you shut the amp down. Bigger filter caps are fine, just be sure to heed the warning about voltage rating. They should be rated at least 600VDC.

 

[Eric Bauder]

I have a Paraglow Manual here. I will work on making a copy.

 

[Paul Joppa]

Paul: I will start scanning it and when I'm done I will send it. feel free to remind me in a bit if I haven't. I do think it's probably cooler that you have it.

I will try...not sure why it's italics...to get those numbers tomorrow. Appreciate the help figuring out what I have.

Doc: yeah, I was using mute as a catch all sorts. right now it's wired to b+ and b- but no actual off abilities..

and I hear you on the 5965. all advice by you folks will be followed.

I like the idea of using DC link caps, as I'll be building the case to suit the build. Any thoughts on upsizing to maybe 200uf each? I am a believer in ps capacitance in general...would that help here, and would I need to be concerned about inrush beyond the b+ switch? perhaps soft start needed too?

It's in italics because you first typed CTRL-I instead of SHIFT-I - at least, that's how I do it accidentally :^)

A scan is fine - whatever is easiest.

The soft start is not necessary, because the driver plate voltage is taken from the 2A3 cathode. That makes a semi-soft start of sorts.

 

[superchunk]

It's in italics because you first typed CTRL-I instead of SHIFT-I - at least, that's how I do it accidentally :^)

A scan is fine - whatever is easiest.

The soft start is not necessary, because the driver plate voltage is taken from the 2A3 cathode. That makes a semi-soft start of sorts.

I would give you the original and I'll keep the scan for myself. Not sure if Eric has one for you instead? Happy to send you the original if not.

 

[tsingle999]

Those are pretty cool looking pieces of history. I am glad you like the sound! I am way out of my league here compared to the other suggestions but I have a couple if they even apply to your amp. I have found MQ grid chokes to improve the sound quality if you can place them where they don't pick up noise. I have also like the sound quality improvements in replacing the cathode cap with a film cap like a Panasonic DC link film cap.

 

[superchunk]

oof...that doesn't look good. they sound so good I'm a bit surprised to see burns...

 

[superchunk]

oof...that doesn't look good. they sound so good I'm a bit surprised to see burns...

Is this garbage, unsafe? what do y'all think happened here?

 

[Paul Birkeland]

What's the AC voltage between those terminals?

 

[superchunk]

What's the AC voltage between those terminals

What's the AC voltage between those terminals?

558

 

[Paul Birkeland]

What are the DC voltages on each pin of the 2A3 in that amp?

 

[superchunk]

What are the DC voltages on each pin of the 2A3 in that amp?

I get:
1. cathode 146
2. plate 428
3. grid 92
4. cathode 146

 

[Paul Joppa]

Those terminals would be labeled 1F and 1S (left to right) if I am correct. That would be the finish and start of the high voltage winding; the tap 1T is opposite 1F on the opposite end of the winding. That suggests this may be arcing, though burning by a misplaced soldering iron is also a possibility. The voltages look good.

The PGP8.1 has been out of production for a long time now, and a replacement would be difficult to find. You may have to live with this for a while. I have no expertise with repair of power transformers so I hesitate to suggest more than cleaning it up gently.

 

[superchunk]

Those terminals would be labeled 1F and 1S (left to right) if I am correct. That would be the finish and start of the high voltage winding; the tap 1T is opposite 1F on the opposite end of the winding. That suggests this may be arcing, though burning by a misplaced soldering iron is also a possibility. The voltages look good enough to say that it's not leaking very much now, but it does make you worry.

The PGP8.1 has been out of production for a long time now, and a replacement would be difficult to find. You may have to live with this for a while. I have no expertise with repair of power transformers so I hesitate to suggest more than cleaning it up gently.

Hmm, yeah kind of a bummer. I suppose I could have a couple of new ones made to spec at some point. I should start looking into not that I suppose don't want to wait for issues to arise.

 

[Paul Birkeland]

I'd agree with PJ that is was either a careless soldering iron, or maybe some debris that got lodged between those terminals temporarily and burned off. I would get some Q-tips and alcohol and try to clean that off gently if you can, but since the voltages are OK, it's not an enormous concern. (what is a concern is that there's carbon there trying to connect the two terminals).

 

[superchunk]

ah yes, I see why that would be a concern, I'll clean it up best I can.

I'm general the wiring kinda freaks me out on these, the first one I took out was two wires soldered together behind unshrink heatshrink, barely holding on that just fell apart when I touched them. I was going to look to do everything at once in the future but I think I should be working on rewiring ASAP.