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[Paragon]

Howdy all!

Been going nuts trying to figure out what to make with this amp. It is a small chassis (6x9.5) that I would like to reuse. below is the schematic for the amp.

The PT has a 1" core. The OT is about a 3/4 core with around a 10k primary.

As for tubes, I have a ez80, some 12ax7, 2 mismatch el84, and also 2 mismatch 6v6gt and a 6x5 (which I thought needed a separate filament winding on the PT which I do not have)

My mind keeps wandering on what to make and would like some insight from those with experience.

I was originally going to make an 18W clone but stumbled on this site and the Liverpool 2x el84 type. How would the liverpool be compared to an 18W? clean headroom? I will probably want to make a 6v6 plexi eventually.. not sure if I should turn this into one or not. The power transformer seems to be right for it (at least for voltage output).
Figuring out current draw with THIS calculator would show and increase of around 12mA on the HV and a slight decrease on the filament if I used a full bridge rectifier.

Any thoughts?

I would like something that has some nice cleans but also a good OD sound for blues and beyond into some hendrix and page and possibly into heavier stuff.

Thanks!


[img976]http://i72.photobucket.com/albums/i172/ ... ematic.jpg[/img]

[ampgeek]

Welcome Paragon! Lots of fun to be had here for sure.

I have built an Express (and a dozen or so others of various breeds) but not the Liverpool so I can't comment from experience on that specifically. Surely, others will.

I had been eyeing an 18W varient when your post came up so I had this already in my minds-eye:

http://www.el34world.com/projects/image ... tout_8.gif

Great group over at the Hoffman site for any required support. Many here participate there too.

Looks like the right amount of holes (your extra tone control could house the "hot switch") along with other similarities. I have to believe that your EZ80 could sub for the 5Y3 but that will need to be checked more closely.

Do you play out and, if so, what size/type of venues? Speaker cab options? Those might play into the clean volume requirements for your final circuit selection.

Is the current amp point-to-point wired? Maybe use a drop in turret or eylet board if that makes sense given the current hole locations. They are pretty easy to make yourself so that might be something to consider if more projects are on the horizon.

Post up a picture of what you have to get more creative juices flowing!

Cheers,
Dave O.

[Paragon]

I'll try to get some photos later. Here is a photo from the internet.

[img:800:600]http://img.photobucket.com/albums/v652/ ... 140140.jpg[/img]

It is currently PTP wiring with a few small strips for ground and power distribution from the PT.

This is actually the second one I bought. The first chassis wasn't in as good condition and did not thave the cover. Came with a bad OT. This second with the cover actually had a bad PT (go figure!!) The PT was on fire at one point. I dissected the coils and it looks like there was arcing in the primary or something as there were sections of melted wire.

Anyhoo.. the

I don't much.. still in the learning stage and currently have a Vox VT30 and AS60VTX (hybrid modeling amps)
I don't gig (obviously with my lack of playing skills) but would like to have some decent clean ability (I can usually clean the sound up with my current rig easily with the volume knob.. especially with the strat)

Looks like any amp I go for will have 5 to 6 pots unless I do a minimal design. I was looking at the Mark Huss 18W TMB, 6v6 plexi, and now the liverpool/2

My main concern is that the PT and/or OT might be slightly under sized looking at the core (I know the original was deemed a 12W but that was a clean amp, not a guitar amp so perhaps the small core OT will be fine)