Dieselpunk Preamp of Doom and the Beast with Two Backs

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Mike H
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#301 Re: Dieselpunk Preamp of Doom and the Beast with Two Backs

Post by Mike H »

jack wrote: Wed Nov 13, 2019 9:33 am Maybe. Maybe not!
Oh yes you may have to look for it. :D
 
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
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Thermionic Idler
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#302 Re: Dieselpunk Preamp of Doom and the Beast with Two Backs

Post by Thermionic Idler »

I realised I hadn't finished this off properly by sharing the completed interior shots, or any decent exterior shots of the amps working. I photographed them this week in the evening after having got a more up-to-date lens for my proper camera, as the light was getting low. It's actually quite tricky capturing glowing valves without them looking pink.

So - left hand amp, exterior:

Image

And its interior wiring:

Image

Right hand amplifier, exterior:

Image

And its interior wiring:

Image

I haven't addressed the oscillation that occurs on one of them if nothing is connected to the inputs yet. :oops: However, other than that they have been largely trouble free since they were completed in November. They are used every night, usually for a good 4 hours or so.
Deck: Garrard 301 - Audio Origami PU7 - NW Analogue DH3S
Phono: Pete Millett LR, Lundahl SUT, AMB σ22 PSU
Linestage: Bruno Putzeys Balanced Pre + Hans Polak relay mod, LCDuino control
Power amps: 300B PP 'Symmetric Reichert'
Speakers: FF225WK Big Mets
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Ray P
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#303 Re: Dieselpunk Preamp of Doom and the Beast with Two Backs

Post by Ray P »

I don't think that looks at all shoddy!
Sorry, I couldn't resist!
Cressy Snr
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#304 Re: Dieselpunk Preamp of Doom and the Beast with Two Backs

Post by Cressy Snr »

Cool...or should that be hot!
Sgt. Baker started talkin’ with a Bullhorn in his hand.
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IslandPink
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#305 Re: Dieselpunk Preamp of Doom and the Beast with Two Backs

Post by IslandPink »

Nice shots, & properly shoddy work there !
"Once you find out ... the Circumstances ; then you can go out"
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Thermionic Idler
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#306 Re: Dieselpunk Preamp of Doom and the Beast with Two Backs

Post by Thermionic Idler »

Thanks all. Hopefully they'll finally make it to Owston in 2021! I'd originally planned to have them there in 2018 but...

2018 - Not ready yet
2019 - Still not ready yet and Owston clashes with trip to Scotland
2020 - Ready, but Covid-19.

Things I still need to do:

Preamp VU meters - as predicted, at most levels there was very little movement most of the time, and now with the Beasts being more sensitive we barely see any movement at all right now. I plan to add a little audio compressor circuit in the line to the meters, which will extend their actual range down to 40dB or maybe even more than that.

Power amps - need to investigate a solution to stop them oscillating with unconnected inputs (I am most grateful for the various solutions that were suggested on this thread). This partly drove my purchase of the Analog Discovery as I wanted to be able to save and compare the results of various tests.
Deck: Garrard 301 - Audio Origami PU7 - NW Analogue DH3S
Phono: Pete Millett LR, Lundahl SUT, AMB σ22 PSU
Linestage: Bruno Putzeys Balanced Pre + Hans Polak relay mod, LCDuino control
Power amps: 300B PP 'Symmetric Reichert'
Speakers: FF225WK Big Mets
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Paul Barker
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#307 Re: Dieselpunk Preamp of Doom and the Beast with Two Backs

Post by Paul Barker »

Shoddy
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
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