Just what we need........another 183 build in progress

UltraHookedOnPhonix · Post by **UltraHookedOnPhonix** » Sat May 28, 2011 8:17 am

Sweet build TM!

I like the pot labels and the heatshrink around some of the hook-up wire. Got the right glass for it too!

Is that a 130V MOV across the line there?

Also, just curious, what's your Source resistance on the FET?

ToneMerc · Post by **ToneMerc** » Sat May 28, 2011 12:27 pm

UltraHookedOnPhonix wrote:Sweet build TM!

I like the pot labels and the heatshrink around some of the hook-up wire. Got the right glass for it too!

Is that a 130V MOV across the line there?

Also, just curious, what's your Source resistance on the FET?

Thanks UHOP. The MOV is a 150V, the Source resistor is a 2.2K and the shunt resistor is 27K. If it wasn't so usuable I would most likely change the Source resistance to around 1-1.2K.

Mike

CHIP · Post by **CHIP** » Sat May 28, 2011 12:51 pm

TM,
Very nice build.
I see you went with an audio taper for the bass pot.
That's what I changed mine to, a 312K audio.

ToneMerc · Post by **ToneMerc** » Sat May 28, 2011 1:15 pm

CHIP wrote:TM,
Very nice build.
I see you went with an audio taper for the bass pot.
That's what I changed mine to, a 312K audio.

Thanks, yep it was easier to find the 300KA and I'm glad that I was lucky enough to get one on the high side. I will say this, I'll take the actual called for pot value more serious now. I guess my next trick to learn is scraping the track to get the value that you desire.

Mike

dogears · Post by **dogears** » Sat May 28, 2011 2:02 pm

Guys, the bass pot is not a big deal. It is a variable resistor. The actual value is not that important. Really.....

ampdork · Post by **ampdork** » Sat May 28, 2011 7:35 pm

Agreed. The value should not be terribly critical unless jazz mode is your thing. But value and taper does add up too. A high value linear is going to more difficult to dial in for some then a low value audio. I have not always had the impression that all dumbles were made with the most ideal tapers....but that is purely my opinion and impressions.

ToneMerc · Post by **ToneMerc** » Fri Jun 24, 2011 2:43 pm

Finally found it's home, a Taylor ODS cabinet. The suede color is actually more grape than purple.

Changed 22k to get the preamp voltages up slightly; string now: 2.76K>18K>2.2K

GE JAN 12AX7WA V1: 198/204V
GE JAN 12AX7WA V2: 198/205V
GE JAN 12AX7WA V3: 313/307V
Gold Lion KT77 V4-V7: 455V/453V screens

David Root · Post by **David Root** » Fri Jun 24, 2011 2:53 pm

Sweet cabinet! Mine is the same but w/brown VOX grille cloth and not suede, smooth blonde Tolex.

Thanx for publishing your dropping resistors and voltages. I have 3K, 2K2, 22K but I also have a parallel off the screen node of 24K, 2K2 for a buffered loop 12AT7. Might have to tweak them a bit when I get it finished. We'll see.

I bought three NIB GE JAN 12AX7WA '75s for $31 on EBay for my build. I guess no-one else was watching. How do you like their tone?

ToneMerc · Post by **ToneMerc** » Fri Jun 24, 2011 3:00 pm

Yep, thanks. I sent Taylor my suede and cloth and he squared me away.

David Root wrote: I bought three NIB GE 12AX7WA '75s for $31 on EBay for my build. I guess no-one else was watching. How do you like their tone?

Damn, I must have missed those

. I love the amp in general, I came into the build thinking that I'm most likely not going to care for the voicing and I was wrong.

Mike

amplifiednation · Post by **amplifiednation** » Fri Jun 24, 2011 3:08 pm

Very nice Mike! Glad the cabinet worked out.

talbany · Post by **talbany** » Fri Jun 24, 2011 3:18 pm

Mike
Amp looks..

Very nice work.Congrats..Keep it up.

All The Best!!

Tony

ToneMerc · Post by **ToneMerc** » Fri Jun 24, 2011 3:23 pm

Tony, I want to thank you as well for all these layouts, enlightenment and when I sometimes need a sanity check.

Thanks Amp Dad

ToneMerc · Post by **ToneMerc** » Fri Jun 24, 2011 3:26 pm

amplifiednation wrote:Very nice Mike! Glad the cabinet worked out.

Thank you again..........I have more suede you know

talbany · Post by **talbany** » Fri Jun 24, 2011 3:28 pm

ToneMerc wrote:Tony, I want to thank you as well for all these layouts, enlightenment and when I sometimes I need a sanity check.

Thanks Amp Dad

M
My Pleasure!!

Rock out!!

T

David Root · Post by **David Root** » Fri Jun 24, 2011 8:03 pm

I just checked my three 12AX7s on my VTV tester.

One is higher gain than the other two but the triodes are not as well DC balanced, so that goes in V1.

One of the remaining two is well balanced, best of the three, maybe 1VDC between triodes, that is going in the PI.

The third one is not that badly balanced, not as good as the PI tube but better than the V1 tube and that is going in V2.

Gain numbers in each pair of triodes are pretty close except the V2 tube, which is not as close as the other two.

I'm curious how others would do their selection.

Tube Amp Archive

Just what we need........another 183 build in progress

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Pimped and completed

Re: Just what we need........another 183 build in progress

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Re: Just what we need........another 183 build in progress

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Re: Just what we need........another 183 build in progress

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