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Massive quad 6l6 mono amplifier

Carbsandcaps

Carbsandcaps

Super Member
Thought I’d share this project of mine from a while ago that I just dug back out. It’s a big quad 6l6 amp from what I believe was a Baldwin organ. It was a very early model, I believe one of the first tube organs they made I can’t remember the model but the organ was huge. I’m guessing it puts out 50 watts. The choke is the same size as a lot of power transformers! I’d love to find another to make two mono blocks. IMG_3630.jpegIMG_3631.jpegIMG_3632.jpegIMG_3634.jpeg
 
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Lavane said:
The frequency response may not be best for home use?
But might be great for a guitar amp?
Click to expand...

Ya I was looking into upgrading the output transformer but not sure I want to put the money into it yet. It would just be for a garage system. I found a matching amp on eBay but I’m not spending $400 on an organ amp.
 
Ya, that's a crazy price. Maybe watch the add and see if the price drops and massage him with an offer.
 
I use three organ amps and all have excellent frequency response for home audio. If they only have a response of 20 to 18K, it's still fine.

****, the bass on these things are awseome by themselves. Besides, I can't hear anything anymore above 15K these days. :rockon:
 
you might get 50 watts out of a quad of 6L6G but thats probably about the end of the world. 40 is a little more realistic

dunno, give it a go and see what it will do. Sometimes limited response is from things outside of the transformer and improvement can be made. My big Bogens are used as PA amps or to drive shaker tables in stock form but with some rework they make fine hifi amps. Not particularly pretty but they sure do rock and roll.
 
Is Battradio (Mark) still around? He was modding the Baldwin's about 20 years ago. Used to have a few threads here on AK...
 
I plan on keeping this one and finding another to match so seems like we’re all in the same boat. There was one on eBay for sale for way too much money. The guy then pulled the tubes and relisted it for $100. It sold within literal seconds. Just missed it.
 
Rex Everything said:
Is Battradio (Mark) still around? He was modding the Baldwin's about 20 years ago. Used to have a few threads here on AK...
Click to expand...
I don't think so. I had pretty regular correspondence with him.
At one point he was having some health issues and soon after his posts slowed. I used some of his schematics for Magnavox console amps along with him helping me with some scratch builds. One preamp I built wound up being sent to him in trade. I didn't get much more responce from him after and his posts slowed, then stopped.
May of 2022 was the last time he logged in.
 
Carbsandcaps said:
Thought I’d share this project of mine from a while ago that I just dug back out. It’s a big quad 6l6 amp from what I believe was a Baldwin organ. It was a very early model, I believe one of the first tube organs they made I can’t remember the model but the organ was huge. I’m guessing it puts out 50 watts. The choke is the same size as a lot of power transformers! I’d love to find another to make two mono blocks.
Click to expand...
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I love those open-air, hand-wound chokes. You don't see that anymore unless you DIY them. :)

Quality parts are everywhere in this unit. :thumbsup:
 
I have several Baldwin PC40s that I acquired to use as bass amps. The transformers are from the 512 series. They have an approximate 20 to 1 turns ratio. The ones that I have are not suitable for hifi use. But fine for a bass amp.

In the thread referenced below look at my posts #7 and #13 for tests that I performed on them.

baldwin pc-40​

I picked up four of these amps. they have no tubes or rectifiers. I see they call for 6l6g output tubes. Im seeing a few different variations of these tubes along with 5881 tubes. Im trying to figure out exactly what tubes will replace the originals alog with the 6l6g?
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Steve
 
steve... said:
I picked up four of these amps. they have no tubes or rectifiers. I see they call for 6l6g output tubes. Im seeing a few different variations of these tubes along with 5881 tubes. Im trying to figure out exactly what tubes will replace the originals alog with the 6l6g?
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Steve
Click to expand...
6L6G GA data sheet.

5881 data sheet.

The 5881 max output (AB1, push-pull) is ~23 watts. The 6L6G and GA are around 19 watts.
 
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IMO, those beasts need a better front end. The OPT iron is OK, and that is a relatively easy swap. They're choke input with the inductor in the ground leg. Nothing crazy there. As for tubes, nearly any of the 6L6 variants will work, but I would recommend those with -GC ratings.

Douglas
 
Looks like a paraphase inverter with on voltage amp stage inside the loop and one outside. Not uncommon for the era, but nothing special either. If its got the three triodes shown, 6SL7 as a long tail pair and the other as a voltage amp might be an improvement without having to change the tube lineup.

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