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Paul Birkeland · 14542

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4krow

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Reply #15 on: December 26, 2018, 09:54:56 AM
 Now that I have had a chance to photo, and disassemble the unit, here is what you are looking at. Basically a Quickie and PJCCS that need attention. I must add that the 3 position Glassware A3 volume control is a stepped attenuator arrangement for 1) master volume (center dial), 2) left and right separate volume (flanking dials). This isn't the issue..... Believe it or not, I am unable to get the PJCCS working when wired to the Q. The Q works on it's own. Each time I make one of these simple kits, this same thing happens when the PJCCS is wired in, i.e. no signal at output. I realize that this is something that I am getting wrong, but I have simply lost patience.
« Last Edit: December 26, 2018, 10:00:59 AM by 4krow »



Offline Paul Birkeland

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Reply #16 on: December 26, 2018, 11:11:01 AM
That's probably a little beyond my skill set. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Paul Birkeland

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Reply #17 on: March 21, 2019, 12:31:59 PM
I took this pair of old Paramours in for repair recently.  One of them somehow developed a short between B+ and the chassis through debris in the 9 pin socket.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Paul Birkeland

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Reply #18 on: March 21, 2019, 12:34:20 PM
Since I had the amps in hand, I talked the owner into letting me install the Iron Upgrade package that we offer for older SEX amps.  It fit, but just barely!  I had to trim off some of the mounting tab on each output transformer so it would clear the wood base.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Paul Birkeland

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Reply #19 on: April 03, 2019, 01:37:43 PM
This project I am building up for my own personal uses.  Way back 20+ years ago, I won a set of 300B-glow amps on eBay back when eBay was pretty new.  I was working at a hifi shop at the time and had them shipped there, and I got to audition the amps against power amps that (at the time) were $25,000+.  Needless to say I don't work at a hifi shop anymore! Anyway, this pair of really old and crusty original "SEX" amps showed up on the local Craigslist for a fair price.  They really have very little left from the original SEX monoblocks, except maybe two of the octal sockets.  The presence of the PGP-8.1 and TFA-204 made it obvious that I should rewind the clock and make some new B-glow amps.  Stay tuned for more photos!

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Paul Birkeland

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Reply #20 on: April 24, 2019, 11:38:18 AM
Much, much earlier this year, I sent out a pair of repair boxes for some "Paramours".  When I eventually received them, they were more like cap coupled Paraglows with lots of Magnequest transformers and fancy parts inside.  Ultimately some flaky hardware was to blame for the issues the amps were having, but I managed to talk the owner into letting me convert these old amps into a fresh stereo amp.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Paul Birkeland

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Reply #21 on: April 24, 2019, 11:42:08 AM
Here's the completed amplifier.  I recycled a significant number of components from the original build, but combined it all into a three sided aluminum enclosure with alder side rails.  To spice things up visually, there's a pair of 100mA ammeters that display the operating current for each 2A3. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline borism

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Reply #22 on: April 24, 2019, 03:38:45 PM
Looks beautiful! How does it sound?

Boris


Offline Paul Birkeland

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Reply #23 on: April 24, 2019, 03:53:15 PM
Looks beautiful! How does it sound?
Excellent, the TFA-2004 is a very solid performer and a big step up from the Speco matching transformer provided with the old Paramour.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline sl-15

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Reply #24 on: April 24, 2019, 04:43:52 PM
Wow that is a very impressive conversion and a neat looking amplifier. Great workmanship!

Stefan Hampel
Soundsmith Carmen, modded Technics SL-1200mkII, Thorens TD 125 mk2 with SME V, Eros, Extended Foreplay III, BeePre2, Crack, Pioneer Spec 4, Sonus Faber Electa


Deke609

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Reply #25 on: April 25, 2019, 03:24:09 AM
Ditto. Looks great. I like what you did with the metal chassis and front and backplates. I may poach that for a re-build I have in mind using copper plate (I don't think my existing 30 gauge will stand up to the test of time)

Those output transformers are HUGE.  Why so big?



Offline Paul Birkeland

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Reply #26 on: April 25, 2019, 06:09:18 AM
Those output transformers are HUGE.  Why so big?
They look bigger in the photos than they are in person.   A transformer stacked with all nickel laminations will also need to be a bit bigger than its grain oriented steel counterpart.
« Last Edit: June 19, 2019, 10:37:42 AM by Paul Birkeland »

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Paul Birkeland

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Reply #27 on: June 19, 2019, 10:42:03 AM
I finally got some spare time to work on those Craigslist amps that I bought.  PJ was kind enough to scan and send me his B-glow manual, and he also provided some information on DC heating a 300B from the PGP8.1.  The chassis plates of these amps are powder coated with green vein powder, the sides are 1/4" cherry over plywood since you don't see the edges, and I used a couple of motor run caps in the power supply.  A little extra B+ is dropped by using a different power supply choke, and bias is monitored with a meter so it can be more precisely adjusted.  A scrap preamp prototype from Doc B's basement provided the old school C4S boards that I thought would be fun to use in this recreation.

If you have a crusty old pair of B-glows sitting around, I am certainly available to freshen them up!

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Karl5150

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Reply #28 on: June 20, 2019, 03:00:41 AM
Beautiful.
I like how each restoration is unique: They all require similar components to function, but the final results are certainly not "cookie cutter". Objets d'art, capable of stimulating multiple senses.

Karl
Downstairs: Planar3>PH-16>Stereomour II>OB Betsy+
Upstairs: RP1>Eros/CD5004>Seductor (2x Monoblocks)>FH3
Office: Modi Uber 2/Sirius>SEX2.1.1>µFonken FF85WK + DC160 subs
BR: FiiO M6>SEX3.0.1>ScanSpeak 10F + TangBand W6 (Mono)/DT770Pro
Garage: X12 streamer>Quicksand>Minimus 77


Offline Paul Birkeland

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Reply #29 on: May 03, 2020, 06:44:52 PM
I managed to snag a pair of Afterglows to complement the B-glows I built last year.  I didn't take a ton of photos of what the amps looked like when they got here because they were totally smashed up in shipping.  All I have is the "inside" shot before they were sent.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man