Manzamp!

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jelle
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Re: Manzamp!

Post by jelle »

Looks great!!! Awesome job, cannot wait to hear what you think and how it starts up...BTW, sleep is for the weak! :twisted:
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ic-racer
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Re: Manzamp!

Post by ic-racer »

"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Manzamp!

Post by ic-racer »

"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Manzamp!

Post by ic-racer »

"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Manzamp!

Post by ic-racer »

"You feel like you're floating on a football field filled with marshmallows." -Dumble
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jelle
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Re: Manzamp!

Post by jelle »

What's up with those surgical tools?! Are you a MD or scientist type like me? :D

Looks absolutely great!! 8) 8)
10thTx
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Re: Manzamp!

Post by 10thTx »

Truly remarkable and very impressive build!

with respect, 10thtx
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ic-racer
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Re: Manzamp!

Post by ic-racer »

Going over everything 100 time paid off. It powered up in stages just fine. I'll admit to getting the diode for the LED indicator lamp wrong but otherwise it makes some nice sounds.
The voltages may be way off, but I can work on that.

I thought I wired the volume controls wrong, but the interactive controls are a 'feature'
"You feel like you're floating on a football field filled with marshmallows." -Dumble
Mark
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Re: Manzamp!

Post by Mark »

The voltages may be way off, but I can work on that.
How far are the voltages off, would using different tubes make a difference to the voltages, what do you consider the effect of the voltage differences to be?
I thought I wired the volume controls wrong, but the interactive controls are a 'feature'
I had heard the Bassman controls were interactive, but I never hear much about that anymore. What volume pots did you use, I seem to remember the posts on the Bassman's had something like a 30% taper and Fender used linear pots on their first reissues.

So what does it sound like?
Yours Sincerely

Mark Abbott
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ic-racer
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Re: Manzamp!

Post by ic-racer »

You tube videos to be downloaded in a few minutes.

Voltages are much higher than the 5f6a schematic. But who knows what the real Manzamp was like.

I played around with the Variac between 90vac and 120vac and I prefer the sound at 120vac. B+ is around 500v, first preamp tube plate about 250v.
No changes at this time. I'll let it settle in a while, realize those measurements are after a total of only 15minutes on-time in its entire life.

I'll put it back on the bench and make sure my power supply wires are all soldered well. I pulled them up during the start up.
"You feel like you're floating on a football field filled with marshmallows." -Dumble
talbany
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Re: Manzamp!

Post by talbany »

In all the Dumble amps I have seen always have around 180-210 on V1 (one had 130) input/recovery,part of the Dumble charm I would think!!..I can't think of any reason why he would deviate from those voltages on the Manzamp?..500v sounds a bit high for a Bassman power :? But hey if it sounds good..
You could maybe try a 5u4 in there and drop about 20 more volts..

Tony
Last edited by talbany on Sat Feb 02, 2013 3:35 pm, edited 3 times in total.
" The psychics on my bench is the same as Dumble'"
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rogb
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Re: Manzamp!

Post by rogb »

What a great build! Love the chassis, love everything about it.

You should be really proud of this.

I hope I'm gonna love the sounds too :D
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rogb
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Re: Manzamp!

Post by rogb »

talbany wrote:In all the Dumble amps I have seen always have around 180-210 on V1 (one had 130) input/recovery,part of the Dumble/Skyline sound I would think!!..I can't think of any reason why he would deviate from those voltages..500v sounds a bit high for a Bassman power :?

Tony
Tony, I've got 503 on my Bassman MC PT :D 244vAC line voltage

Mark suggested why:
======================================

Hello Roger,

Please see the attached specification sheet for our 40-18029. Please see the actual measured voltages in the lower left hand corner. These are actual measured voltages with all windings loaded to FULL rated load currents. Each set of taps was tested with different rectifier tubes. The voltages were measured after the unit was loaded for a few hours...

All voltages will read higher with less than full load current, when the unit is cold, and when used with solid-state rectifiers.

Mark Sacketti
V.P. of Engineering

Magnetic Components, Inc.
===================================

30v zener on its way now, still the amp sounds really good, especially the cleans, just shooting for some Feedback City "zhoosh" or whatever it's now called lol. Playing with the NFB for now.
tubedogsmith
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Re: Manzamp!

Post by tubedogsmith »

talbany wrote:..500v sounds a bit high for a Bassman power :? But hey if it sounds good..Tony
Especially with a JJ rectifier, I've found them to drop voltage more like an 5Y3 or something.

Great looking build there IC!! I can appreciate all the work you put into it!!
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Structo
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Re: Manzamp!

Post by Structo »

Looks real nice IC. :D
Tom

Don't let that smoke out!
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