Mcintyre POW Prince o wails questions...

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tubedood
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Mcintyre POW Prince o wails questions...

Post by tubedood »

Hi there and happy 4th! Any of you all have any experience in this build? It was featured in Guitar Player in the 90's. I tried it before and failed, now I'm wanting to try again! It starts life as an old Fender Princeton non- reverb. I'm hoping for tips on a turret board to use and layout ideas. I posted this on the general forum wanted it also in the Fender one (Sorry for the re-post).

Have a safe 4th,
Dale
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martin manning
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Re: Mcintyre POW Prince o wails questions...

Post by martin manning »

From what I read here http://www.blueguitar.org/new/articles/other/pow.zip the amp in the article was constructed by modifying a SF Princeton Reverb. If there is no modified layout diagram available, then I suggest working your way through the POW schematic and marking up the Fender layout. http://ampwares.com/amplifiers/fender-s ... on-reverb/
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xtian
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Re: Mcintyre POW Prince o wails questions...

Post by xtian »

No wonder you failed. That's a high parts count. That "Brilliant" switch appears to ground the cathode of V1b. Will that even pass signal when closed?
I build and repair tube amps. http://amps.monkeymatic.com
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martin manning
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Re: Mcintyre POW Prince o wails questions...

Post by martin manning »

xtian wrote:That "Brilliant" switch appears to ground the cathode of V1b. Will that even pass signal when closed?
No problem there, it just puts a 47n bypass cap across the cathode resistor.
tubedood
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Re: Mcintyre POW Prince o wails questions...

Post by tubedood »

Thanks for the tips! Yep there's a lot of parts going on in there, after reading up on this forum I'm a firm believer now in keeping that signal chain as clean and easy as possible. I'll try again to see if I can get her to work!

Dale
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xtian
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Re: Mcintyre POW Prince o wails questions...

Post by xtian »

martin manning wrote:
xtian wrote:That "Brilliant" switch appears to ground the cathode of V1b. Will that even pass signal when closed?
No problem there, it just puts a 47n bypass cap across the cathode resistor.
Now I see it. Thanks.
I build and repair tube amps. http://amps.monkeymatic.com
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rooster
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Re: Mcintyre POW Prince o wails questions...

Post by rooster »

Hm. The Mid control (not the middle control) is something new to me. If you ever get this operating per the schematic tell me about this control please. I remember his Bass Breaker schematic back in the day but I never saw this circuit. Hm.....
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tubedood
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Re: Mcintyre POW Prince o wails questions...

Post by tubedood »

Hi rooster!
From what I remember with the last attempt at this build that 'Mid" was a tuned tone control that seemed to boost/cut the frequencies at about 630hz. It did affect the tones but I wasn't too sure on my craftsmanship back then. As soon as I finish my 5F1 I'm going to attempt this modded Princeton again. After that I'm eager to try a Rocket with Ya'alls guidance !

Dale
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rooster
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Re: Mcintyre POW Prince o wails questions...

Post by rooster »

Yes, update me. It is interesting to see the use of a mic/line matching transformer in an amp and I'm very curious to hear what it might add to the stock tone controls. Happy to help with the Rocket when it comes up if I can. 8)
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Vince
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Re: Mcintyre POW Prince o wails questions...

Post by Vince »

rooster wrote:Yes, update me. It is interesting to see the use of a mic/line matching transformer in an amp
It's used as inductor in series with cathode bypass cap. HAD did something like this in his Manzamp.
chris_sanford
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Re: Mcintyre POW Prince o wails questions...

Post by chris_sanford »

Vince wrote: Mon Aug 15, 2016 5:26 pm It's used as inductor in series with cathode bypass cap. HAD did something like this in his Manzamp.
Not quite the same implementation though. Note that the LC element(s) in the POW are actually connected to both the cathode and plate (roundaboutly). It's my understanding that out-of-phase nature of that connection provides the ability to obtain a mid-cut, but please feel free to jump in and correct me, filter experts. :)

There are some old Ampegs that do something similar. Check out the V9: http://drtube.com/schematics/ampeg/v9pre-jp.gif

Cheers,

chris
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