selecting / ordering the transformers for Rocket & Express

Express, Liverpool, Rocket, Dirty Little Monster, etc.

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idnotbe
Posts: 24
Joined: Sat Mar 18, 2017 2:25 pm

selecting / ordering the transformers for Rocket & Express

Post by idnotbe »

i am going to try my first build - one Rocket and one Express.
and want to buy very good sounding transformers.

after reading a few thread, i am going to order from Heyboer with the specs on this site :
http://www.toneslut.com/transformers/


1. for Express, (2 * EL34)

International Power Transformer (i need 220v input)
Primary: 240V
HV Taps: 300 - 260 - 0 - 260 - 300 (300mA)
Heater Tap: 6.3V (7.5A)
Rectifier Tap: 5V (3A)

Standard Output Transformer (i want crunchier, more modern tone rather than vintage)
Primary: Dual 5200 / 6600 Ohms
Secondary: 4 / 8 / 16 Ohms
Steel: M27
Watts: 35 (conservatively)

did i pick the right ones?


2. if i want to add a choke to Express for tighter & modern voicing, what can be the spec?


3. for Rocket, (4 * EL84)

i think "International Power Transformer" on the website works for Rocket too.
but not sure about the OT.

i read Rocket OT is made with the special winding (reverse winding?) for hi-fi sounding.
what's the exact spec to order??


4. For Rocket, what's the exact spec for the choke?


5. if i show the site to a Heyboer sales guy, can i order the right transformers?
in other words, are the specs on the site enough & complete to order the transformers?
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Ron Worley
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Re: selecting / ordering the transformers for Rocket & Express

Post by Ron Worley »

Heyboer made me a multi voltage Express PT that worked great. I made this amp for a mate in the U.K, but needed US mains to be able to test it before shipping it. I don't remember the price, but it was very reasonable. I think Phil at Heyboer will know what you want.
Ron
telentubes
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Re: selecting / ordering the transformers for Rocket & Express

Post by telentubes »

rj, a member of this forum, has done most of the transformer homework for Rockets and LPs, has them custom made and offers them for sale. You may want to check his site, rjguitars.net, and see what's available. Hopefully he will see this post and chime in.
Bob S
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Re: selecting / ordering the transformers for Rocket & Express

Post by Bob S »

+1 on rj.
Rj is very well respected here - for good reasons.
Contact him through his website - even just for advice.
Why Aye Man
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M Fowler
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Re: selecting / ordering the transformers for Rocket & Express

Post by M Fowler »

I would contact www.rjguitars.net and buy the Pacific or Mercury transformers or get a kit which is the best option.
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RJ Guitars
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Location: Los Alamos, New Mexico
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Re: selecting / ordering the transformers for Rocket & Express

Post by RJ Guitars »

You guys are very good to me... I appreciate that! I have Pacific winding a 120/240 tap Wreck spec PT for me that will include a 5V rectifier tap as well. These should be in my hands late next week. The Heyboer and Mercury Mag trannies are also very good and I'm still partial to those that Edcor wind for me. Thanks again, rj
Good, Fast, or Cheap -- Pick two...

http://www.rjguitars.net
http://www.rjaudioresearch.com/
http://diyguitaramps.prophpbb.com/
Mark
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Joined: Sat Jan 15, 2005 8:10 am
Location: Sydney Australia

Re: selecting / ordering the transformers for Rocket & Express

Post by Mark »

I don't think I'd be ditching the choke resistor for a choke. The choke resistor does provide some sag to the preamp. The power supply is otherwise quite stiff.
Yours Sincerely

Mark Abbott
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