Use only the latest docs. That's the only true representation of the circuit. ZP doesn't care for rectifier tubes so much, and a 100 ohm sag resistor gives about the same effect as an ez81 rectifier tube. Less money and more reliable.
First Amp Build Question
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Re: First Amp Build Question
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Re: First Amp Build Question
I'm having some difficulty trying to narrow down which is the latest TMB schematic/layout. It all looks like it is from 200x. If that's the latest available, that's cool. I'll figure it out and work in the latest grounding schemes.
Does the 18watt crowd have a favorite chassis for a head build?
Does the 18watt crowd have a favorite chassis for a head build?
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Re: First Amp Build Question
The top of the page, where it says "newest version" in huge lettersJP77 wrote: ↑Wed 01/13/21 2:47 amI'm having some difficulty trying to narrow down which is the latest TMB schematic/layout. It all looks like it is from 200x. If that's the latest available, that's cool. I'll figure it out and work in the latest grounding schemes.
Does the 18watt crowd have a favorite chassis for a head build?
viewtopic.php?f=25&t=24430
That's from 2020.
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Re: First Amp Build Question
Was looking over that schematic just now. Wondering if you've detected any issues resulting from driving the tone stack with the anode, rather than from a cathode follower. Have you run this in a simulator or swept it to see how much it varies from the original Marshall design?
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Re: First Amp Build Question
That’s interesting,i’ve Been looking at the hiwatt custom 20 preamp and that tonestack is driven by the plate and I was wondering the difference.
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Re: First Amp Build Question
I seem to remember reading that cathode drive prevents the volume from changing so much when the stack is adjusted. Don't know how significant this is in the real world though.
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Re: First Amp Build Question
I've built plenty of them, and they're great amps. It was designed by Zaphod_Phil, who is an EE and professional amp builder/designer, as well as a founding member of this site.TriodeLuvr wrote: ↑Wed 01/13/21 12:13 pmWas looking over that schematic just now. Wondering if you've detected any issues resulting from driving the tone stack with the anode, rather than from a cathode follower. Have you run this in a simulator or swept it to see how much it varies from the original Marshall design?
This is not an "original Marshall design." It's an original ZP design, with the 18W power section.
lol, for that matter, there aren't many "original" Marshall designs either; they stole most of them.
Thanks,
Josh
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Re: First Amp Build Question
I'm still leaning toward a two channel build.JMPGuitars wrote: ↑Wed 01/13/21 8:04 amThe top of the page, where it says "newest version" in huge lettersJP77 wrote: ↑Wed 01/13/21 2:47 amI'm having some difficulty trying to narrow down which is the latest TMB schematic/layout. It all looks like it is from 200x. If that's the latest available, that's cool. I'll figure it out and work in the latest grounding schemes.
Does the 18watt crowd have a favorite chassis for a head build?
viewtopic.php?f=25&t=24430
That's from 2020.
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Re: First Amp Build Question
No preferred chassis? I was considering picking up the chassis from GDS along with the transformers unless there is a better chassis.
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Re: First Amp Build Question
The "Modern Classic" series is probably the safest bet for a two channel version.
I have my own chassis made, there are plenty of good options from popular suppliers. The GDS transformers are great.
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