Whats on your amp workbench?

Amp tinkerers and people who aren't afraid of 700 volts or so in here....

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Lyle
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Re: Whats on your amp workbench?

Post by Lyle »

Had another go at the Jansen today. The circuit doesn't match up 100% with the schematics I've found online, but it does match photos I've seen of amp from the same time so I guess they changed it a bit over the years.

Waiting for some parts to arrive, I think some of the coupling capacitors are leaking which is causing the weird voltages I'm seeing.

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Re: Whats on your amp workbench?

Post by RectifiedAmps »

Lyle wrote: Sun Apr 17, 2022 4:55 pm Had another go at the Jansen today. The circuit doesn't match up 100% with the schematics I've found online, but it does match photos I've seen of amp from the same time so I guess they changed it a bit over the years.

Waiting for some parts to arrive, I think some of the coupling capacitors are leaking which is causing the weird voltages I'm seeing.
What kind of voltages are you seeing, and where?

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Re: Whats on your amp workbench?

Post by Lyle »

RectifiedAmps wrote: Mon Apr 18, 2022 8:45 am
Lyle wrote: Sun Apr 17, 2022 4:55 pm Had another go at the Jansen today. The circuit doesn't match up 100% with the schematics I've found online, but it does match photos I've seen of amp from the same time so I guess they changed it a bit over the years.

Waiting for some parts to arrive, I think some of the coupling capacitors are leaking which is causing the weird voltages I'm seeing.
What kind of voltages are you seeing, and where?
B+ is high and then everything else after that. Plate voltage sitting at 600v. I checked the bias and it's sitting at 130% plate dissipation.

I've still got more stuff to tidy up and I think one of the power tubes might be on the way out.

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Re: Whats on your amp workbench?

Post by JHorner »

Got a couple of weeks use from the Microblock 45, now it is a headphone amp only. Nothing happening at the speaker out.

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Re: Whats on your amp workbench?

Post by PaulWD »

16505019603553379857608535764100.jpg
16505019603553379857608535764100.jpg (6.31 MiB) Viewed 966 times
Got a few more old projector cabs from the 50-60s. I've put 5c1 ish things in them in the past. I might try and squeeze a 5e3 into one. Or something earlier from here: http://prewaramps.org/
Last edited by PaulWD on Sat Aug 13, 2022 1:04 pm, edited 1 time in total.

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Re: Whats on your amp workbench?

Post by MikeC »

Looks like you are gonna be very busy soon!

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Re: Whats on your amp workbench?

Post by jeremyb »

If you're needing an 8" 8 ohm speaker I have the HH one out of my laney cub I'd part with for cheap :)
Polar Bear wrote: It will continue to be a mystery as to why this is such a sausage fest.

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Re: Whats on your amp workbench?

Post by robthemac »

jeremyb wrote: Thu Apr 21, 2022 1:39 pm If you're needing an 8" 8 ohm speaker I have the HH one out of my laney cub I'd part with for cheap :)
[does math on how much JB has spent on this Laney compared to a higher-spec amp, green numbers cascade down field of vision]

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Re: Whats on your amp workbench?

Post by jeremyb »

robthemac wrote: Thu Apr 21, 2022 1:46 pm
jeremyb wrote: Thu Apr 21, 2022 1:39 pm If you're needing an 8" 8 ohm speaker I have the HH one out of my laney cub I'd part with for cheap :)
[does math on how much JB has spent on this Laney compared to a higher-spec amp, green numbers cascade down field of vision]
Its not that bad to be honest, the whole thing owes me $700 max... not bad for a jensen speakered champ!
Polar Bear wrote: It will continue to be a mystery as to why this is such a sausage fest.

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Re: Whats on your amp workbench?

Post by IMOCD »

jeremyb wrote: Thu Apr 21, 2022 2:05 pm
robthemac wrote: Thu Apr 21, 2022 1:46 pm
jeremyb wrote: Thu Apr 21, 2022 1:39 pm If you're needing an 8" 8 ohm speaker I have the HH one out of my laney cub I'd part with for cheap :)
[does math on how much JB has spent on this Laney compared to a higher-spec amp, green numbers cascade down field of vision]
Its not that bad to be honest, the whole thing owes me $700 max... not bad for a jensen speakered champ!
Is the stereo setup working well?

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Re: Whats on your amp workbench?

Post by jeremyb »

IMOCD wrote: Thu Apr 21, 2022 2:56 pm
jeremyb wrote: Thu Apr 21, 2022 2:05 pm
robthemac wrote: Thu Apr 21, 2022 1:46 pm

[does math on how much JB has spent on this Laney compared to a higher-spec amp, green numbers cascade down field of vision]
Its not that bad to be honest, the whole thing owes me $700 max... not bad for a jensen speakered champ!
Is the stereo setup working well?
I probably need to test the amps further away from each other to get some stereo separation but it’s super cool running the pair at once!
Polar Bear wrote: It will continue to be a mystery as to why this is such a sausage fest.

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Re: Whats on your amp workbench?

Post by clubhouse »

PaulWD wrote: Thu Apr 21, 2022 12:49 pm 16505019603553379857608535764100.jpg

Got a few more old projector cabs from the 50-60s. I've put 5c1 ish things in them in the past. I might try and squeeze a 5e3 into one. Or something earlier from here: http://prewaramps.org/
Wow :clap: ...nice brood...clutch...raft...whatever the collective noun is. And thanks for the website tip...I've some m'self and want to do something similar in time. Any chance you could post what you've done already and updates on stuff to come?

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Re: Whats on your amp workbench?

Post by jeremyb »

Update on the Laney Cub 8 Super, with the speaker and tube swap I'm absolutely loving it with my strat for JM-esque tones, sounds awseome with the ODR-1 on and the volume down on the guitar, delicious.

As far as with dirt pedals and the strat the rams head muff I have sounds epic with it, not really digging my other ODs with it apart from the ODR-1, but with humbuckers they're all sounding great!
Polar Bear wrote: It will continue to be a mystery as to why this is such a sausage fest.

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Re: Whats on your amp workbench?

Post by Optical »

JHorner wrote: Mon Apr 18, 2022 9:56 am Got a couple of weeks use from the Microblock 45, now it is a headphone amp only. Nothing happening at the speaker out.

Image
What are the three ICs on that board?

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Re: Whats on your amp workbench?

Post by JHorner »

Optical wrote: Fri May 06, 2022 1:35 pm What are the three ICs on that board?
I can't find a schematic, but I believe they are all useless broken cunts.

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