Hammond AO-44 conversion

[tubenit]

I bought a Hammond AO-44 with the hopes of using ECL84's which didn't work out.  So, I decided to make it a single ended amp similar to a Fender Champ but with a 5E3 tone stack. I was able to make this conversion fairly inexpensively in that I had a speaker, tubes, wood, grill cloth and many components left over from other projects.  Maybe $185-200 total?

It sounds great! Very happy with it. Despite the exceptionally crowded chassis,  it's almost dead quiet at idle. I'm thinking it's probably around 4-5 watts total?  I initially tried it with NFB, but like it better without ......... so it currently doesn't have NFB.

I didn't want to use 6GW8 tubes as they aren't manufactured anymore and they're expensive.

Instead I used a 12AV7 in V1 and Tung-Sol 6V6 and a JJ EZ81. 


With respect, Tubenit

[tubenit]

It's almost the same size cab as a VibroChamp.  I set it up so I can switch to a 10" speaker later IF I want to.  It has a Weber 8"  8ohm currently.  And the OT is a Champ replacement that allows 4 ohm or 8 ohm choice.


The cab top is spalted maple and there is some trim on the front spalted maple also.  The front panel is a scrap piece of black walnut that I book matched.


All and all, I'm pleased with it.        I will say the small chassis was a challenge to wire up, but any concerns about floor noise disappeared after turning it on and playing it a couple of hours.


With respect, Tubenit

[Latole]

Nice job !

[Platefire]

Sweet looking amp tubenit!!! Very nice work! You must of got it right the first go around. You didn't mention any tweaking other than the NFB.
I love my Champ also. Funny, it's the first amp I built and now seems to be my main amp I use now. I have done some tweaking over the years. Anyway Great Job

[dogburn]

Looks great! And it's nice when you can cobble something together with bits you have lying around.

With adding a tone control, wouldn't it be pretty close to a 5F2a Princeton?

[pullshocks]

Tubenit, what power transformer did you use?

[tubenit]

I used the Hammond AO-44 power trannie that came with it.


With respect, Tubenit

[tubenit]

If anyone would like to hear how the amp sounds, I did a quick demo here:


Old R&B tune new amp build


With respect, Tubenit