Ultimate Hammond Conversions thread

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eniam rognab
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Re: Ultimate Hammond Conversions thread

Post by eniam rognab »

that tone sucking fiberglass? gawd why dont i just short out my PT......
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Blackburn
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Re: Ultimate Hammond Conversions thread

Post by Blackburn »

Formica's where the tone's at!
eniam rognab
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Re: Ultimate Hammond Conversions thread

Post by eniam rognab »

Blackburn wrote:Formica's where the tone's at!
if that tone is a kitchen counter-top! what are you making down there in texas

"amp souffle" bar-beee-cue fender dogs? southern style marshall chitlin's?
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Blackburn
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Re: Ultimate Hammond Conversions thread

Post by Blackburn »

Crazy cool lookin' build so far! :D

You should really do a dedicated thread for your build so people can really check it out. Spread the Hammond repurposing even further!
eniam rognab
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Re: Ultimate Hammond Conversions thread

Post by eniam rognab »

Blackburn wrote:Crazy cool lookin' build so far! :D

You should really do a dedicated thread for your build so people can really check it out. Spread the Hammond repurposing even further!
hey thanks buddy! thats a great idea! i could even record some tracks or something.... i finished up all the wiring today, gonna bring it to school tomorrow for all the fan-saaay test equipment. current limiter n such power her up good'n slow

thread created, her name "ham-rock" http://ampgarage.com/forum/viewtopic.php?t=24959
darefugee
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New build

Post by darefugee »

So I built a couple amps using pieces from a pair of AO-29 chassis, and there are some tubes left over. I want to use them in a new amp build or maybe build some preamp modules. Don't want to buy any new tubes, just use up the ones laying around.

I have a few 6au6 and 6ba6 pentodes and some 6c4 and 12au7 triodes. I'm thinking maybe a low-power bedroom amp using the 12au7s in push-pull with a pentode or two in the front end, shooting for a Vox-y sort of sound. Anyone try anything like this yet?
Thanks,

Roger
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xtian
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Re: Ultimate Hammond Conversions thread

Post by xtian »

I like the Hammond 12au7 as push-pull power in my AX84 Firefly!
I build and repair tube amps. http://amps.monkeymatic.com
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donzoid
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Re: Ultimate Hammond Conversions thread

Post by donzoid »

Well, its been a while. Hell I could put a whole thread about that on Garage Talk better than here. Anyway my first 18 watt, cathode-biased beast is up n running. And she is uuuhuuuugggly. Inside AND out. But sounds good! Don't try to shame me into cleaning it up...but rest assured I am already ashamed of the internal appearances.

Ended up going to a 30uF power cap and a 5y3, put a 10uF Kemet cap on v1b bypass (footswitchable) and its sounds much tighter this way than when it started with a 5u4, on a 50uF supply cap. It was way too mushy on the bass side then, but seems to really like this 5y3 and the final tweek will be to try another 10 to 14.7 uF on V1a bypass as its tight now, but still a bit bassy. Headshell is almost ready and she will be along for the ride at next Friday's gig along with the Express!
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lord preset
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Re: Ultimate Hammond Conversions thread

Post by lord preset »

An update on my AO-39 to Lite IIb conversion. So far no one has been foolish enough to buy my lovely creation on Craigslist, so in the intervening weeks I had time to grow dissatisfied with the lack of headroom and general swampiness of the thing. Arguably that's what it should be but it's really not my style, so I decided to try the AC-15 lite circuit that sluckey included in his conversion write up.

It actually sounded quite cool on the bench - not much more headroom but it definitely had a nice voxy vibe to it. Unfortunately when I popped the chassis back in the cabinet, the EF86 began howling right off the bat. The cabinet is fairly small and is made of pine so lots of resonant vibration is unavoidable. The same tube does fine in my AC30 clone and tube dampers were of no help.

So I bagged that idea and looked for a different 12ax7 based simple preamp circuit to try and settled on a Matchless Spitfire. I followed the Spitfire values for V1 and the tone stack but left the original cut control and PI values as is. Howling was gone, a bit less mush, but still not there. The last tweak was to pull the rectifier tube and pop in an octal SS rectifier I had on hand. Now the amp is a bit louder and punchier - and probably as good as it's going to get. The transformers in the AO-39 are pretty small so there is only so much volume and punch to be had. So back to Craigslist, but this time I will have a harder time describing exactly what it is. :roll:
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Re: Ultimate Hammond Conversions thread

Post by donzoid »

Aw, she's not THAT ugly once she puts her makeup on. Shown here on top of her evil twin (the Express). First show tomorrow afternoon...outdoors too! I'm hoping someone will get some video so I can post a link for those who want to hear her "squeal".
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lord preset
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Re: Ultimate Hammond Conversions thread

Post by lord preset »

donzoid wrote:Aw, she's not THAT ugly once she puts her makeup on. Shown here on top of her evil twin (the Express). First show tomorrow afternoon...outdoors too! I'm hoping someone will get some video so I can post a link for those who want to hear her "squeal".
Not ugly at all and very cool with the twin. Clips are in order.
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lord preset
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Re: Ultimate Hammond Conversions thread

Post by lord preset »

Some pics of the final mods.
lord preset wrote:An update on my AO-39 to Lite IIb conversion. So far no one has been foolish enough to buy my lovely creation on Craigslist, so in the intervening weeks I had time to grow dissatisfied with the lack of headroom and general swampiness of the thing. Arguably that's what it should be but it's really not my style, so I decided to try the AC-15 lite circuit that sluckey included in his conversion write up.

It actually sounded quite cool on the bench - not much more headroom but it definitely had a nice voxy vibe to it. Unfortunately when I popped the chassis back in the cabinet, the EF86 began howling right off the bat. The cabinet is fairly small and is made of pine so lots of resonant vibration is unavoidable. The same tube does fine in my AC30 clone and tube dampers were of no help.

So I bagged that idea and looked for a different 12ax7 based simple preamp circuit to try and settled on a Matchless Spitfire. I followed the Spitfire values for V1 and the tone stack but left the original cut control and PI values as is. Howling was gone, a bit less mush, but still not there. The last tweak was to pull the rectifier tube and pop in an octal SS rectifier I had on hand. Now the amp is a bit louder and punchier - and probably as good as it's going to get. The transformers in the AO-39 are pretty small so there is only so much volume and punch to be had. So back to Craigslist, but this time I will have a harder time describing exactly what it is. :roll:
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lord preset
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Re: Ultimate Hammond Conversions thread

Post by lord preset »

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donzoid
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Re: Ultimate Hammond Conversions thread

Post by donzoid »

Dayummm! LOVE that tone. What guitar/pickups?
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lord preset
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Re: Ultimate Hammond Conversions thread

Post by lord preset »

donzoid wrote:Dayummm! LOVE that tone. What guitar/pickups?
A Reverend Flatroc. It's got Filtertron-ish HBs.
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