63 Vibroverb RI and bigger OT?

Steven · February 4th, 2004, 05:14 AM

Got myself a 63 Vibroverb RI witch I like a lot. I´ve changed the bright cap to 0,120pf, put in a Weber "Copper Cap" module simulating the zag of a 5U4GB rectifier and I´ve replaced the stock speakers with one Weber 10A125 speaker and one Celestion Vintage 10. I´ve also use a home made ext cab with the same speakers. I´ve read somwhere that you can put a "bigger" OT in this amp to improve the sound. I would like to have a little more solid bass response in the amp. Would a bigger OT help? What kind of OT should I look for? A Bassman OT? If I was to replace the OT, is there any other components that need to pe changed also?

tlpruitt · February 5th, 2004, 12:07 PM

Go here to see the OTs that Allen amps offers.

http://www.allenamps.com/transformers.html

You would need a 4 ohm OT with a 4K primary. They have one upgrade OT that should bolt right on with no modifications (mounting holes to drill). Email them if you have any questions. They are great to deal with.

-Tim Pruitt

Steven · February 7th, 2004, 12:29 AM

Contacted Allen Amps but he didnt ship overseas :x . OK, I´ll keep on looking... Thanks anyway :) !

Big Cookie · February 7th, 2004, 11:02 AM

Try a Mercury Magnetics or Mojo Blackface Bassman output trans, either will give you the IRON that it needs to punch up the Vibro RI.

Steven · February 8th, 2004, 03:21 PM

If I did go ahead and changed the OT, is there any other components in the amp that need to be replaced at the same time or can I leave everyting else just as is? Am I correct in assuming that all OTs have the same colour code on the leads? (so if I was supposed to do the change myself I just have to connect all the leads in the same way that the old OT is connected? (I´m sort of a Newbie when it comes to the insides of a tube amp, but I do have good soldering skills and a lot of respect for the high voltages that lurks inside...).

tlpruitt · February 9th, 2004, 10:59 AM

Wiring in a new OT is not tough. Most new OTs come with a wiring schem with the wire colors. Don't assume the wire colors will be the same as the stock OT. You need a primary for 2 6L6's and a 4 ohm secondary.

The tricky part is mounting the OT of the new one does not have the same mounting hole placement as the stock one. If the mounting holes don't match then you have to drill new holes in the chassis to mount the new OT. None of this is brain surgery.

It's a shame you can't get an OT from Allen amps delivered to you. They have an oversized OT with stock mounting holes (and I think stock wire colors) that would be a breeze to install and really beef up the low end. You would get almost no OT saturation with a 4 lb OT in that amp.

-Tim Pruitt

tlpruitt · February 9th, 2004, 11:01 AM

Swapping the OT does not require any other changes.

-Tim Pruitt

Steven · February 9th, 2004, 01:23 PM

and yes I would have liked that Allen OT i guess but thats the way it is. I´m in the process of buying an BF Bassman-type OT from Mojotone instead. I did a quick check on my Vibroverb and saw that the colours on the leads to/from the OT was the same as the Mojotone with the exception of one in tyhe secondary, but I think I will be able to install it myself without killing me in the process :D .

Steven · February 10th, 2004, 03:20 PM

but does anyone have one of these lying around and wanna sell it???

Allen amps output transformator:

Upgrade Output Transformer for Vibrolux™, Tremolux™, Bandmaster™, Pro™, and Vibroverb™ amps. Same 2-bolt 3-9/16" mounting centers means NO DRILLING on your vintage chassis. 1-3/4" (VS 3/4" on stock OT) stack of high-performance lamination steel results in less insertion loss and extended low-end performance. 4lbs VS the stock 2.25 lb unit. Will not fit the non-reverb Pro without drilling. Unit is 1" wider than the originals. 4 and 8 ohm taps with 4,000 ohm primary. Paper bobbin with paper-layered interleaved windings.
#TO40MT $59

I wanna get me one but Allen Amps dont ship outside the States. Anyone that just happens to have one they dont need and wanna sell it to me?????????????????

Guess not... :(

February 4th, 2004, 05:14 AM	#1 (permalink)
Steven Tele-Holic Join Date: Mar 2003 Location: Sweden Posts: 511	63 Vibroverb RI and bigger OT? Got myself a 63 Vibroverb RI witch I like a lot. I´ve changed the bright cap to 0,120pf, put in a Weber "Copper Cap" module simulating the zag of a 5U4GB rectifier and I´ve replaced the stock speakers with one Weber 10A125 speaker and one Celestion Vintage 10. I´ve also use a home made ext cab with the same speakers. I´ve read somwhere that you can put a "bigger" OT in this amp to improve the sound. I would like to have a little more solid bass response in the amp. Would a bigger OT help? What kind of OT should I look for? A Bassman OT? If I was to replace the OT, is there any other components that need to pe changed also?

February 5th, 2004, 12:07 PM	#2 (permalink)
tlpruitt Tele-Meister Join Date: May 2003 Location: Baltimore, MD Posts: 230	Allen Amps has a few OTs that would work. Go here to see the OTs that Allen amps offers. http://www.allenamps.com/transformers.html You would need a 4 ohm OT with a 4K primary. They have one upgrade OT that should bolt right on with no modifications (mounting holes to drill). Email them if you have any questions. They are great to deal with. -Tim Pruitt

February 7th, 2004, 12:29 AM	#3 (permalink)
Steven Tele-Holic Join Date: Mar 2003 Location: Sweden Posts: 511	Thanks tlpruitt Contacted Allen Amps but he didnt ship overseas :x . OK, I´ll keep on looking... Thanks anyway :) !

February 7th, 2004, 11:02 AM	#4 (permalink)
Big Cookie Banned Tele-Holic Join Date: Mar 2003 Location: Ennis, Texas Posts: 693	OT's Try a Mercury Magnetics or Mojo Blackface Bassman output trans, either will give you the IRON that it needs to punch up the Vibro RI.

February 8th, 2004, 03:21 PM	#5 (permalink)
Steven Tele-Holic Join Date: Mar 2003 Location: Sweden Posts: 511	Thanks Big Cookie!!! If I did go ahead and changed the OT, is there any other components in the amp that need to be replaced at the same time or can I leave everyting else just as is? Am I correct in assuming that all OTs have the same colour code on the leads? (so if I was supposed to do the change myself I just have to connect all the leads in the same way that the old OT is connected? (I´m sort of a Newbie when it comes to the insides of a tube amp, but I do have good soldering skills and a lot of respect for the high voltages that lurks inside...).

February 9th, 2004, 10:59 AM	#6 (permalink)
tlpruitt Tele-Meister Join Date: May 2003 Location: Baltimore, MD Posts: 230	Wiring is not tough Wiring in a new OT is not tough. Most new OTs come with a wiring schem with the wire colors. Don't assume the wire colors will be the same as the stock OT. You need a primary for 2 6L6's and a 4 ohm secondary. The tricky part is mounting the OT of the new one does not have the same mounting hole placement as the stock one. If the mounting holes don't match then you have to drill new holes in the chassis to mount the new OT. None of this is brain surgery. It's a shame you can't get an OT from Allen amps delivered to you. They have an oversized OT with stock mounting holes (and I think stock wire colors) that would be a breeze to install and really beef up the low end. You would get almost no OT saturation with a 4 lb OT in that amp. -Tim Pruitt __________________ Art is making something out of nothing and selling it. FZ

February 9th, 2004, 11:01 AM	#7 (permalink)
tlpruitt Tele-Meister Join Date: May 2003 Location: Baltimore, MD Posts: 230	Nothing else has to change Swapping the OT does not require any other changes. -Tim Pruitt __________________ Art is making something out of nothing and selling it. FZ

February 9th, 2004, 01:23 PM	#8 (permalink)
Steven Tele-Holic Join Date: Mar 2003 Location: Sweden Posts: 511	Thanks tlpruitt... and yes I would have liked that Allen OT i guess but thats the way it is. I´m in the process of buying an BF Bassman-type OT from Mojotone instead. I did a quick check on my Vibroverb and saw that the colours on the leads to/from the OT was the same as the Mojotone with the exception of one in tyhe secondary, but I think I will be able to install it myself without killing me in the process :D .

February 10th, 2004, 03:20 PM	#9 (permalink)
Steven Tele-Holic Join Date: Mar 2003 Location: Sweden Posts: 511	Real long shot... but does anyone have one of these lying around and wanna sell it??? Allen amps output transformator: Upgrade Output Transformer for Vibrolux™, Tremolux™, Bandmaster™, Pro™, and Vibroverb™ amps. Same 2-bolt 3-9/16" mounting centers means NO DRILLING on your vintage chassis. 1-3/4" (VS 3/4" on stock OT) stack of high-performance lamination steel results in less insertion loss and extended low-end performance. 4lbs VS the stock 2.25 lb unit. Will not fit the non-reverb Pro without drilling. Unit is 1" wider than the originals. 4 and 8 ohm taps with 4,000 ohm primary. Paper bobbin with paper-layered interleaved windings. #TO40MT $59 I wanna get me one but Allen Amps dont ship outside the States. Anyone that just happens to have one they dont need and wanna sell it to me????????????????? Guess not... :(