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Topic: Fender preamp |
Chris Erbacher
From:
Sausalito, California, USA
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Posted 19 Sep 2003 12:21 pm |
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hey out there, just brainstorming here and am in need of some answers. i was wondering if someone out there has ever used a chassis for a fender twin as a preamp and then ran the signal into another amp, one with more power. if somone did this would it work? i guess i am unsure as to exactly how these things work, and am wondering if the capacitors inside the chassis would give that sweet coloration to the sound even if it weren't hooked up to the rest of the amp, and considering the speakers were the same, if that makes any sense. as to how this relates to my situation, i play a zb d10/11 thru a webb with a jbl and it seems that most of the guys i listen to that have played a zb have used a twin. i love my webb, and am wondering if there is some way to combine the preamp section of a twin (ie the caps and wiring and such) and still run this into the webb to achieve the ultimate union in sound? or would this be overkill and just a waste of time? or not work at all? or would the signal be changed by the webb because it is at the end of the signal chain? the way i figure it, the caps are for coloration and sweetness (i could be way off base here) and the webb is for clarity and power, not to mention lots of control with the eq being what it is. just brainstorming here and thought this sould be a good place to ask a question, thanks in advance  |
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Michael Lewis
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Posted 19 Sep 2003 1:14 pm
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Hey Chris,
There are some forumites that are much better qualified to answer (J.B. Arnold, where are ya?) but I can tell you this much. The Twin can be modified to a preamp out - Buddy Cage and others have done it for years. The key than would to go from the twin to a power amp and speaker cab. I don't know if the Webb comes with a tap into the power amp section, but if it doesn't, running the preamp into the Webb would be double preamping and you probably wouldn't be pleased with the result. The idea is sound and the preamp section of the twin is so wonderful it has been emulated by numerous companies. I hope this helps.
Mike
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Chris Erbacher
From:
Sausalito, California, USA
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Posted 19 Sep 2003 3:00 pm
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| yeah the sound i like is that chicken pickin' sweet sound, like garcia, tom brumley, cage and others who used a zb thru a twin, however, i was trying to avoid a complete change of amps, especially since for the most part i am stoked with my webb, and i am getting a pretty nice sound out of it. i was just wondering if my idea was accurate or not, i am always tinkering and looking for newwness in the search for the exact sounds i hear in my head. i did catch the post by jb arnold a while back and my curiosity was raised as a result of it, but i'm not sure i want to spend another heapof money to see if i can get that sound. i know garcia had the ultimate system with the two twins as preamps and the macintosh power amp pushing the already ample signal thru his hard trucker cabs, quite a sound, and in stereo at that. does anyone know how they were able to get the impedance matched between the twin preamps in that system and the power amp? thanks again for the help. |
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Ken Fox
From:
Nashville GA USA
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Posted 19 Sep 2003 4:16 pm
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| The Alembic F2-B is basically a two channel Showman preamp that is used to drive a power amp. The preamps for Showman, Twin, Super, Pro, Deluxe, and even a Princeton are basically the same. Some have reverb and others do not. The F2-B schematic would be a good quide to doing what you want. You must have a speaker load on a Fender amp or it will kill the output transformer. To avoid this, pull the output tubes out when using the head as preamp. I have a copy of the Alembic preamp. If you want it just send me an email. |
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Bill Hatcher
From:
Atlanta Ga. USA
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Posted 19 Sep 2003 9:14 pm
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| Alembic F2B----just the best!!! |
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Bob Metzger
From:
Waltham (Boston), MA, USA
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Posted 20 Sep 2003 4:11 am
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Every MI amp is basically three parts: preamp, power amp, power supply. Any amp can be made into an active preamp, essentially by disconnecting and and standbying (Did I invent a new word?) the power amp. The Twin Reverb is no different.
You can modify the device to make a 'line out' as implemented by Fender on later examples of the Twin R. which will accomplish your goal or make a 'preamp out' which is somewhat similar in function but different in sound. Once you've isolated the preamp as a device, you can tweak, modify, re-design it to make it a powerful preamp tool in its own rite. There is, to my knowledge, no generally accepted adaptation (mod) of this device as a preamp which people are endorsing universally. Hence, enter the Alembic. That doesn't mean it isn't possible; it just means it hasn't been done on a 'mass' level yet. I've heard individual examples of Twin/Showman preamps (essentially the same thing) that sound fantastic.These have been 'one-offs' and the circuit hasn't been released to the public or isn't available. It's all about the point in the circuit one decides to 'pick off ' the signal and how it's integrated to the power amp. This is design work, best done by an experienced tech. There's no reason that once the preamp is designed and passes the sound test that it can't be built into a suitable sized enclosure (small) and used as a outboard device for recording and/or live gigs with a suitable power amp (like a Webb). It just hasn't been done yet, except for the Alembic, and ,of course, other preamps. If you have the will to do this and can follow thru, you could make this happen but the road may not be a straight line.
BTW, to 'standby' the Fender Twin power amp (so you can use a Twin Reverb amp as a preamp device; think pin  is easy.
Have fun,
Bob M.[This message was edited by Bob Metzger on 20 September 2003 at 05:30 AM.] [This message was edited by Bob Metzger on 20 September 2003 at 07:18 AM.] |
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Bob Hoffnar
From:
Austin, Tx
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Posted 20 Sep 2003 5:59 am
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A big part of the twin sound is from the 6L6 power tubes and the transformer. A pre amp out will not give you the sound of a twin.
I put a vote in for the Alembic F2B also if you want to go the pre amp / power amp route. It can sound great but does not really sound like a twin.
Bob
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Bob Metzger
From:
Waltham (Boston), MA, USA
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Posted 20 Sep 2003 6:12 am
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This is where the design part comes in. To just add a 'preamp out' jack is only a small part of the idea. There are other steps to take to make this idea a workable reality. I've heard excellent examples of this on a one-off basis.
One must consider that a possible reason for not using the Twin Reverb amp as is, is the power amp and the 6L6's. Could it be possible that certain folks like the sound of a Fender preamp but wished it could be competently matched and coupled to a very clean and powerful solid state power amp? Of course, this might not sound like a Twin but then again, it might be something that alot of players would really like alot. Until it's created, who is to say?
I also would say that I bet the Alembic wasn't designed expressly for steel guitar use, if you get my drift.
Bob M.[This message was edited by Bob Metzger on 20 September 2003 at 07:28 AM.] [This message was edited by Bob Metzger on 20 September 2003 at 07:33 AM.] |
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Donny Hinson
From:
Glen Burnie, Md. U.S.A.
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Posted 20 Sep 2003 7:59 am
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| I'd suggest using a graphic EQ with your present amp, you might be surprised! A good graphic equalizer will allow you to "contour" the sound, and emulate the sound of other amps (sans all that "overdrive" stuff). The tone controls (usually only 3 or 4) in most amps are very limited in what they can do. An active graphic equalizer, with as few as 6 or 7 bands, is far superior, IMHO. |
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Chris Erbacher
From:
Sausalito, California, USA
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Posted 20 Sep 2003 4:04 pm
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| so what you guys are saying is that the caps used don't really color the sound and give it the sweetness? (i'd like to avoid another thread denoted to tone, because everything in the chain will affect it if you ask me) according to the posts i've read here, i got the notion that the caps in different variations would give you the different types of tones and general vibe, in the twin amp. for instance some guys like the orange drops, but the jb arnold post talks about others. is my thinking off base? when i look at garcia's rig, i see a blackface and a silverface twin put into one cab, stripped of it's speakers. then they ran the signal into a power amp and into a hard trucker cab with three jbl's and i think another to act as a passive transducer (this one you can't tell it's there, or i am completely wrong). to my ears, this is a sweet sound, and i was wondering if the reason for this is because of the preamp. any more help out there? i really appreciate the replys so far, thanks. |
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Bob Metzger
From:
Waltham (Boston), MA, USA
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Posted 20 Sep 2003 4:16 pm
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I think that your thinking on the subject is clear and you should experiment away and see if you can make it work. The magic will be in the details, though.
If you're speaking of Jerry Garcia of the Grateful Dead, I doubt that any gear that he used was stock. Just focus on your own stuff and get it as good as you can. This sounds to me like a noble experiment. Let us know how it comes out; you've got me interested now.
Bob M. |
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Chris Erbacher
From:
Sausalito, California, USA
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Posted 22 Sep 2003 1:58 pm
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| bump |
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