Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: sluckey on December 01, 2015, 09:32:27 am
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I picked up this Hammond AO-63 last February for $20. This is a lot of amp on one chassis. Actually, its a complete 7591 main amp plus a complete 6GW8 reverb amp and two power supplies.
I wanted to convert to something but was not sure what. I finally decided to leave the main power amp alone and just replace the organ preamp with an Ampeg Gemini II preamp. Sounded good with a lot of potential but I couldn't decide what else to do with it, so it sat on the bench until October.
Then I got the idea to use the reverb driver and recovery (without the reverb power amp). After playing around for about a day I had a great sounding reverb section married to the Ampeg preamp. I had a lot of stuff just temporarily solder together at this point. Couldn't even flip the chassis over. So I proceeded to clean it up with proper soldering. While I was at it, I removed the reverb power amp components except for the tube sockets.
Then I added a Vibroverb 6G16 tremolo circuit. This circuit works very well with 7591s since the bias voltage is lower than 6L6s. I was very pleased with the trem effect. I did add a blinky LED just for eye candy.
I finally added a fresh faceplate to hide all the original chassis cutouts. I'm calling it done. I can't decide what to name it. It's mostly Hammond with a touch of Ampeg and Fender. Any ideas? It has a nice clean, warm sound that reminds me of my old Gemini II. Plenty of power too. It looks rough but it's a keeper! Here's the schematics. Pics to follow.
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Before pics...
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Conversion pics...
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FHamPeg
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cool conversion and very nice work. has kind of a franken-amp motif going with that cabinet. ;-)
--pete
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"FHamPeg" How would a Southerner pronounce that?
has kind of a franken-amp motif going with that cabinet. ;-)
That's just a temporary 'amp cradle'. That's probably all the cabinet it will ever get though! :icon_biggrin:
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"FHamPeg" How would a Southerner pronounce that?
has kind of a franken-amp motif going with that cabinet. ;-)
That's just a temporary 'amp cradle'. That's probably all the cabinet it will ever get though! :icon_biggrin:
Faaa-Haaammm-PEG with a sloooowwwww draaaawwwlllll :icon_biggrin:
why no nice cabinet?
--pete
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Ha-Gemini Revo ???
Lots of premium Mullards in there. Bet it sounds sweet. :icon_biggrin:
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How would a Southerner pronounce that?
DAT?
after dat, gator slayer, bent fender, peggy lu.....I love the southern drawll :icon_biggrin:
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How would a Southerner pronounce that?
DAT?
Got me! :l2:
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sorry, couldn't let that one pass by :icon_biggrin:
Nice (re)build btw
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Still looking for a name. Remember, it's a Hammond AO-63 with an Ampeg Gemini II preamp and Fender Vibroverb tremolo.
So far I've got "FHamPeg" and "Hamtone GemiVibe". Any more ideas out there?
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VibroRocket.
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FenPegVerbalo
Model A063 GemII
kinda sounds like a Johnny Cash Cadillac song :icon_biggrin:
EDIT
since my southern roots is Appalachia hill I think the pronunciation would be something like;
"Hot-damn boy, ain't she uh butte" followed by a good chew-spit-lip-wipe for literary emphasis :icon_biggrin:
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verbgemiond 63
--pete
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Hammer (HAMmond AMpeg FendER)
Though I think just 'Hampeg' with out the F is pretty cute
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Call it The Warbler.
Make sure you post about it in all the amp forums, post about it on your own webpage, and see how long it takes a silly manufacturer to get bent out of shape about the name... :l2:
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Still looking for a name. Remember, it's a Hammond AO-63 with an Ampeg Gemini II preamp and Fender Vibroverb tremolo.
So far I've got "FHamPeg" and "Hamtone GemiVibe". Any more ideas out there?
Gem Hammer
Gemmond
or
Hammond Vibrogem
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Lucky
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Vibropeg.
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I'm kinda liking Hampeg GemiVibe. Hope I don't step on any toes with that name! :icon_biggrin:
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Hafmmenderpeg Gemivibroniverb AO-II-63
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Before I seen anyone's reply, I thought "Hampeg" . So I'm happy with your selection. Could you hang the Reverb tank off the bottom of the top Cab panel in the front? You got a good deal on the amp for $20 and you've made into something good. Great job! Platefire
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Slu-AO Vibe.
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Could you hang the Reverb tank off the bottom of the top Cab panel in the front? You got a good deal on the amp for $20 and you've made into something good.
I've found an even better way to mount the tank. I used the original "L" brackets and mounted it on the back side of the chassis. The price was actually $19 and shipping was $18. No tubes were included but that's still a great price for what I got. Haven't seen one that cheap since April.
Tubenit, how would you pronounce "Slu-AO Vibe"? (Ain't gonna give shooter another shot! :icon_biggrin: )
Still liking that Hampeg and GemiVibe (pronounced Jimmy Vibe)
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Slu-AO vibe Slew A Oh vibe :icon_biggrin:
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SlamPeg?
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Ain't gonna give shooter another shot
I'm just a one shot wonder anyway :icon_biggrin:
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Hey guys, I went with "Hampeg GemiVibe". I dressed it up a bit too. Still not much more than a simple three board chassis stand. Easy to flip into any position. I'm calling it done this time. Really. :wink:
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Well done! did you have the grill or diy it? and is the top board maple?
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Oooooooooooooo nice!
My plate is pretty full at the moment and itch'n to get into this one.
I had thoughts of keeping the reverb as is and making a combo with two speakers but having a closer look at the chassis and those huge trannys might make it very heavy.
Looks great Sluckey.
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Looks Awesome !! We are missing a way to upload sound samples here, I think lots of people would like to hear the sounds of all those amps posted in the forum !
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Y'all are too kind! :smiley:
The top is clear coated mahogany. I made the front grill using a sheet of expanded sheet steel from Lowes. 3/4"water pipe to roll the bend. 1/2" aluminum strips for the trim were bent then glued using JB Weld. Rustoleum patio furniture paint. I had everything except the expanded sheet and the chest handles. That poor man's cab cost me under $20. :icon_biggrin:
Timbo, save the schematic in my first post. It has the original plus my conversion schematics. Might come in handy sometime.
Kinda wish I had a website again! Here's one last pic...
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Nice! :icon_biggrin:
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Looks Awesome !! We are missing a way to upload sound samples here, I think lots of people would like to hear the sounds of all those amps posted in the forum !
There are several ways to get a sound clip here. Look in the "sound clips" forum. You'll find plenty of clips as well as how to post them.
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Der Hampeg! it's done!
wery wery nice!
industrial with style. kudos
--pete
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I think I'll put a big Raytheon sticker on the back! :laugh:
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I think I'll put a big Raytheon sticker on the back! :laugh:
oh no's! then it for sure will stop working! :wink:
that's like slapping on the yankee version of the lucas electric curse... :BangHead:
--pete
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Nah! I know a lot of retired FAA technicians who are now on Raytheon's payroll. They'll take good care of me! :l2:
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Oh yeah, this is where the reverb tank went...
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I looked at the finish product earlier and was wondering how you did the reverb but I see you have revealed the mystery. Man! The amp really looks sharp sluckey. That light face plate and expanded metal cover looks great against that darker wood. Very impressive. You got the touch :bravo1:
Platefire
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Looks Awesome !! We are missing a way to upload sound samples here, I think lots of people would like to hear the sounds of all those amps posted in the forum !
There are several ways to get a sound clip here. Look in the "sound clips" forum. You'll find plenty of clips as well as how to post them.
I was thinking about to post the sample in the same thread as the amp is shown, maybe with that small player, idk just an idea. By the way, where is the sample your amp !!?
Lets hear it !!! :m11
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Done. Thanks
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Very cool and impressive build! I like the cab head too! THANKS for sharing your stellar work.
With respect, Tubenit
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Very nice. I love the silver Marshall knobs against the white and the polished industrial look is awesome. Especially the old washtub type handles.
Does she sound like the ampeg from your younger years? Is it tough to get the power tubes to breakup? I guessing it is more clean and swirly. I only have 1 Ampeg and it is a 6V6 PP, but it does have the diamond cloth.
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Ed, I think it sounds like my old Gemini II. But that's been a long time since I heard that amp. My hearing has changed considerably and sometimes I don't trust my memory too much either! But it does have a nice clean warm tone. I like it best through my Jensen C12N. Playing through my Sunn 2x12 with Celestion Heritage G12H really brings out the bottom end, but I like the single 12" Jensen sound better. My Jensen P12N is too bright for my taste. And the Celestion Blue is too bright also. I wish I could try that Jensen 15" Concert Series that was in my old Gemini.
Breakup? It stays clean all the way up to hurting my ears. I ain't heard any breakup! :laugh:
Just had a thought. I'm gonna try my Emi 15" Big Ben tomorrow. Here's one more pic. You'll get a laugh out of this!
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Those Avatar cabs are held in hi regard. :icon_biggrin:
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Ed, I think it sounds like my old Gemini II. But that's been a long time since I heard that amp. My hearing has changed considerably and sometimes I don't trust my memory too much either! But it does have a nice clean warm tone. I like it best through my Jensen C12N. Playing through my Sunn 2x12 with Celestion Heritage G12H really brings out the bottom end, but I like the single 12" Jensen sound better. My Jensen P12N is too bright for my taste. And the Celestion Blue is too bright also. I wish I could try that Jensen 15" Concert Series that was in my old Gemini.
Breakup? It stays clean all the way up to hurting my ears. I ain't heard any breakup! :laugh:
Just had a thought. I'm gonna try my Emi 15" Big Ben tomorrow. Here's one more pic. You'll get a laugh out of this!
You just cannot decide on knobs or input jacks for your AC15 can you? I really like the Avatar cab, but I am surprised to hear you say the Celestion is bright sounding with the Hampeg. Prolly because it is a very clean amp and does not compress easily.
That is why I asked about breakup. I had a Gemeni around for a couple of months and it just got loud, but I did like the sound. Hard to explain an Ampeg tone since we are so used to hearing Fenders. They seem to have a balanced sound like a Port City Pearl.
I'll bet you will like your Big Ben. Don't you have a Weber Cali 12?
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Don't you have a Weber Cali 12?
That's right, I do! It's in my Leslie. The Cali brightness is tamed a lot by the Leslie cab with the cheese block sitting directly in front of the cone. I'll give it a try.
I finally put a jump switch on the AC-15. Rather than drill another hole, I just pulled one of the input jacks. I now use a single jack and can switch between either channel or both with the 3 position toggle.
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Nice Score and Fine Conversion :thumbsup: :thumbsup:
Franco
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Just beautiful Steve. I really like it. I miss your website. It was like coming over to you house once in awhile to see what you had been doing.
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I'm working on it Barry. Maybe a nice Christmas present for me. I'll be sure to let you know if I get the site back online. I already have a page for this AO-63 conversion.
...Steve
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Steve,
Curious if you have tried the Weber? I have been thinking of getting a couple and want to know what you think of them against your Celestion Blue. Like in what way they are different.
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Yes, I've tried it. Bottom end is very solid. But the brightness is kinda muffled because of the Leslie cab. Kinda like having a huge beam blocker in front of the speaker.
But, this Cali had a very bright in your face high end when in my TDR cab. Bottom end was solid too. Reminds me of the sound of a JBL D120 smooth cone. If it sounds so bright to me I wonder what someone with good ears would say?
I don't even know how to compare it to the Blue.