Manzamp - Revisited!

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Smitty
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Re: Manzamp - Revisited!

Post by Smitty »

Nice work! Thanks!!
Mark
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Re: Manzamp - Revisited!

Post by Mark »

It’s something else. Pity it’s a tougher built.
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dorrisant
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Re: Manzamp - Revisited!

Post by dorrisant »

Mark wrote: Fri Apr 21, 2023 9:38 am It’s something else. Pity it’s a tougher built.
How so? If you can get the board, most of the preamp connections are made and the wiring seems simple compared to an ODS or the like. I will work on a PCB with Kicad. Then I can post the gerbers so anyone can get a board from wherever they may be. The board could be installed in a larger chassis to make it easier. I may do just that for a head version of this amp at some point.
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Mark
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Re: Manzamp - Revisited!

Post by Mark »

dorrisant wrote: Sat Apr 22, 2023 4:24 pm
Mark wrote: Fri Apr 21, 2023 9:38 am It’s something else. Pity it’s a tougher built.
How so? If you can get the board, most of the preamp connections are made and the wiring seems simple compared to an ODS or the like. I will work on a PCB with Kicad. Then I can post the gerbers so anyone can get a board from wherever they may be. The board could be installed in a larger chassis to make it easier. I may do just that for a head version of this amp at some point.
The choke in the first preamp stage was a hurdle for me as I don’t know where I would buy one.

The chassis is a piece of u shaped aluminium.
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Reeltarded
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Re: Manzamp - Revisited!

Post by Reeltarded »

Many cheap organs from 60s/70s have small 10h inductors. You might find one at a trash dump that has a bag full.

Send a message to Cbass. He ganked a Lowery and had a bunch.
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gktamps
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Re: Manzamp - Revisited!

Post by gktamps »

I have a ton of various coils and inductors. What does this one look like? What is the form factor?
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dorrisant
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Re: Manzamp - Revisited!

Post by dorrisant »

gktamps wrote: Mon Apr 24, 2023 3:46 am I have a ton of various coils and inductors. What does this one look like? What is the form factor?
This is what ic-racer used... Looks like three tied in series, maybe...
https://ampgarage.com/forum/viewtopic.p ... 01#p451401
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dorrisant
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Re: Manzamp - Revisited!

Post by dorrisant »

Mark wrote: Sun Apr 23, 2023 1:39 pm
The chassis is a piece of u shaped aluminium.
I think it could be built in a tweed Bassman chassis and certainly could be built in a BF Bassman chassis with a little rearrangement. I may mock up a board in Kicad and post the gerbers for anyone who wants to have one made.
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dorrisant
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Re: Manzamp - Revisited!

Post by dorrisant »

gktamps wrote: Mon Apr 24, 2023 3:46 am I have a ton of various coils and inductors. What does this one look like? What is the form factor?
Also, ic-racer posted on that he used three inductors he bought off of eBay. 1.0H each for 3H total. So if you like the tone in his clips that might be a target. One of the schematics denotes what looks like "I-22Hy". I wonder what the difference in mid boost would be and also how to calculate it.

https://ampgarage.com/forum/viewtopic.p ... 16#p237916
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Reeltarded
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Re: Manzamp - Revisited!

Post by Reeltarded »

The resonant peak is easy if you use any web calculator. Look for one with q factor as well and some even do bandwidth.

Now, the rest is hard and very confusing. There is no ser/para calculator for RLC, R/CL... nothing. There is paper and pencil and I have a headache from holding a pencil.

I have a stage that is .68u/2k7-500mH pushes 270Hz and has around 3.15 Q. I set for peak instead of trough.

POST 9k5. I have slacked, but humming like a radio.
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Reeltarded
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Re: Manzamp - Revisited!

Post by Reeltarded »

Another place to search is car audio. They use lots of useful values in networks of bandpass and high pass. Maybe even some $5 used amplifier has gold in there.
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ic-racer
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Re: Manzamp - Revisited!

Post by ic-racer »

The amp is still sounding good! Here is a recent one:

https://youtu.be/lugriVPJA7A?si=vErDPJR8FN5KIl8u
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ic-racer
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Re: Manzamp - Revisited!

Post by ic-racer »

Good to see some interest in the Manzamp. Especially since the EJ amp has surfaced. Like, what in the heck is a Manzamp preamp? My impression of the Manzamp I build was the tone was in the power amp section.
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Screen Shot 2023-09-06 at 7.42.50 PM.png
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Re: Manzamp - Revisited!

Post by Roe »

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Re: Manzamp - Revisited!

Post by jazzbass »

Hi Roe,

for me the price of the amp on Reverb of €389,375.01 seems like real madness, I point out the .01. :shock:

Franco
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