Anyone AGAINST using a Twin for PSG?

Chris Rice · Post by **Chris Rice** » 9 Jan 2014 1:52 pm

Tim Marcus wrote:
Chris Rice wrote:
Tim Marcus wrote:In fact, there's not a single amp that Leo Fender designed that uses EL84 tubes.
6G9 Tremolux used 6BQ5/EL84 power tubes briefly.
http://www.thevintagesound.com/ffg/tremolux_blonde.html
That's the one exception that I mentioned nice find!

Ah, I thought you were referring to the Musicmaster Bass with the 6AQ5 power tubes. Also odd.

Chris Rice · Post by **Chris Rice** » 9 Jan 2014 1:56 pm

Marty Broussard wrote:Hey guys two quick questions:

Are the Twin Reverb and Super Reverb the same circuitry with Twin having more power ?

Are both channels the same with just effects added on one?

Thanks!!

The blackface Twin Reverb has a mid knob on the normal channel, the Super Reverb does not. The Super Reverb is tube rectified, the Twin Reverb is diode rectified. Other than that (and the extra pair of tubes and beefier transformers to get more power out of the Twin Reverb), I believe the circuit is pretty much the same.

The effects channel has an extra gain stage to make up for signal loss in the reverb and tremolo. The channels sound similar, but not the same.

Marty Broussard · Post by **Marty Broussard** » 9 Jan 2014 2:00 pm

Thanks Chris!

Tony Prior · Post by **Tony Prior** » 10 Jan 2014 7:48 am

Atom Schmitt wrote:Well, I'm glad to see nobody thinks this is a silly idea.

I'm starting to think the only problem this Twin is going to present for me is that I'm going to be torn between using it for guitar and using it for steel.

Well Atom, if it's a silly idea you are about 50 years late with the notion!

Ok , on to the next problem, The Twin Reverb, has probably been the #1 double duty amp for Guitar/Steel players for 40 years or more ! Not to worry, ONE twin Reverb has got you covered with both of your Instruments ! Join the family !

Oh and just for those that may think it is too heavy..ok , a stock Twin comes in at around 68 pounds ( no JBLs') A Nashville 400 is around 60 pounds, a Session 500 is over 70 pounds..a Vox AC30 is 65 pounds.. Yes, the Twin is around 68 pounds but thats not the reference, the reference is , how much heavier is it than the amp you are lugging now ? If you are lugging 60 pounds..it's plus 8, not plus 68...

Use the twin..live a Little !

Tim Marcus · Post by **Tim Marcus** » 10 Jan 2014 8:25 am

Chris Rice wrote:
Marty Broussard wrote:Hey guys two quick questions:

Are the Twin Reverb and Super Reverb the same circuitry with Twin having more power ?

Are both channels the same with just effects added on one?

Thanks!!
The blackface Twin Reverb has a mid knob on the normal channel, the Super Reverb does not. The Super Reverb is tube rectified, the Twin Reverb is diode rectified. Other than that (and the extra pair of tubes and beefier transformers to get more power out of the Twin Reverb), I believe the circuit is pretty much the same.

The effects channel has an extra gain stage to make up for signal loss in the reverb and tremolo. The channels sound similar, but not the same.

and they are out of phase with each other because of that extra triode

the Musicmaster, I think, was designed in the CBS days - making the Tremolux the odd duck. Post CBS its a crapshoot - lots of strange designs and lots of "improvements" to Leos designs that were actually pretty bad.

As far as the weight goes, a Twin with a single 15" Neo Speaker will be very light. The older the Twin, the more likely you will find one with a removable front baffle. A new baffle is about $75 - put in a Telonics speaker and the amp will weigh under 60 pounds.

Jack Hanson · Post by **Jack Hanson** » 10 Jan 2014 12:42 pm

Atom, perhaps this will help answer your question:

http://www.nbc.com/the-tonight-show/vid ... /?tin=2090

Chris Boyd · Post by **Chris Boyd** » 10 Jan 2014 12:53 pm

Paul would sound amazing through the Sears "amp in case" setup! The backline Twin sure sounds great..

Ken Metcalf · Post by **Ken Metcalf** » 10 Jan 2014 4:18 pm

A Twin is not a Twin

I have owned a reissue, a mid 70s, a 1970, a 66 Showman and now a 67 Blackface. and not all Twins are created equal.
Some just sound better that others even from the same years.

A well maintained with good quality speakers is a safe bet.

Atom Schmitt · Post by **Atom Schmitt** » 15 Jan 2014 12:07 pm

Well, I survived the weekend for the most part, using the Twin. It nearly killed me a few times because it's got an ungrounded plug, but that'll be replaced this week. I took a look and realized that it's got one Jensen speaker (C12Q?) and one peculiar replacement of dubious origin.

It was a lot harder to dial in the tone I was looking for with this amp, trying to strike a balance between having enough cut and ripping my ears off, but I still liked it. Although my Black Box blew up on me on Saturday night... at first I was thinking it was the amp blowing up. At set break I started checking everything to see where the issues were coming in, and as soon as I pulled the SGBB out everything returned to normal, but I didn't realize how much I like the sound of that unit out in front of everything, because the highs sounded a lot more brittle for that second set, which made the EQ-ing even tougher. But, after this is all fixed, life should be good. I probably just need to replace the 12AX7 in the Black Box.

Tim Marcus · Post by **Tim Marcus** » 15 Jan 2014 3:57 pm

your dangerous grounding may have taken out the black box

make sure you put a grounded power plug onto the twin and have it converted properly, removing the "death cap" and ground switch. Put a 1/2" hole plug to cover up the hole after pulling the switch

don't let your tech put the ground wire under the power transformer lug either - its not safe - it needs its own ground lug or something that will not loosen over time.

Mitch Ellis · Post by **Mitch Ellis** » 15 Jan 2014 4:15 pm

Tim Marcus wrote:

As far as intermodulation is concerned, that can easily be designed out of a tube amp. Remember that the Twin was ultimately still designed for guitar - with a few careful modifications you can lose the ghost note and still have a gorgeous and powerful sounding amplifier

Tim,
What is intermodulation distortion? Does it have something to do with the fact that there are two speakers? How can it be easily designed out? I have a '72 twin with the original JBL D120F speakers and when using it for steel, it sounds great.....at a low volume. When I increase the volume to a less than moderate level, it begins to distort just a little. In fact, some have told me that they don't hear any distortion. Others say "Yea, maybe a little." I have the master volume on 10 and the channel volume on about 7 or 8. I always use a Nashville 400. Have I just simply gotten use to the sound of it? Thank you.

Mitch

Dave Hopping · Post by **Dave Hopping** » 15 Jan 2014 7:03 pm

Chris Boyd wrote:Paul would sound amazing through the Sears "amp in case" setup! The backline Twin sure sounds great..

I saw it was a very clean-looking silverface,which got me wondering whether it was a reissue or an original.

Jerry Van Hoose · Post by **Jerry Van Hoose** » 15 Jan 2014 7:14 pm

Regarding the Fender Twin Reverb on The Tonight Show, it looked to be an original, given the appearance of a master volume control on the far right side of the control panel. Also, there wasn't a "drip edge" surrounding the grill which is present on the "68 reissue".

Atom Schmitt · Post by **Atom Schmitt** » 16 Jan 2014 7:46 am

Tim Marcus wrote:your dangerous grounding may have taken out the black box

Ugh. Hopefully it's not too expensive a trip to the tech.

Lane Gray · Post by **Lane Gray** » 16 Jan 2014 8:16 am

Mitch, intermodulation distortion is when two notes combine to make a third. It's usually the result of another form of distortion: even the almost undetectable forms (there's some distortion that sounds clean, but a scope would reveal oddities).
If you have an overdrive box, you can hear IM on your steel. Hit strings 5 and 8 with the fuzz on: if you're in tune you'll hear a G# in the background, and it'll dive to a lower A as you hit the A pedal.
And it's an electronic artifact, not an acoustic one, so one speaker vs. 2 will have no effect.

Mitch Ellis · Post by **Mitch Ellis** » 16 Jan 2014 6:38 pm

Lane,
I don't have an overdrive box. The man that I got the amp from told me that he bought it new in '72 and that it was all-original, but that a repairman had "gone through it". If it has the original tubes, would changing them help? If so, which ones should I buy? Again, the distortion isn't awful, it just gets a little "fuzzy" sounding when the volume gets to a certain point. Can a '72 twin be made to sound as clean at a high volume as a Nashville 400? Thank you for your help.

Mitch

W. Van Horn · Post by **W. Van Horn** » 20 Jan 2014 10:49 pm

First, I love playing steel through my twin.
Someone mentioned doing double duty w/ both channels - on my early 70s non-master volume twin I have noticed that the tone settings on the first channel effect the sound of the second channel.
For example, if I am playing through the vibrato channel and turn up the EQ and/or vol knobs on the dry channel, I can hear it.
Maybe it's voodoo I'm inventing, maybe it's particular to my amp. I always turn all knobs on the channel I'm not using to zero because I hear a difference on the channel I'm playing.
Anyway, Twins are good steel amps.