Pacific transformers Versus Heyboer transformers?

[Mark]

As there are some people at the site who have the Two Rock kits and the Heyboer transformers, I was curious if you guys could do an A/B test of these two transformers.

Look forward to hearing some feed back on these transformers.

[dotyduke]

+1

[Mark]

I have heard that the Pacific transformers are very good. Though I don;t know which is better or just how they are different sounding.

[dotyduke]

Thanks.

[doctord02]

Mark, maybe PM Glen (geetarpicker) about the differances... I understand that when he built his two clones he went with the Pacific trannys because thats whats in his original Wreck... But I think he also played around with a clone that someone else built that used the Heyboers. Or Allyn, he'd know...

I've only used the Heyboer iron... The build Paul Ruby made for me had the original 5.2K OT that Doug Holt sold, and the one I built for myself used the Toneslut iron with the 6.6K tap. Both sound fine and any differance could be any of a million little things.

I have a 4.2K Schumaker OT that I'll use for a Rocket/AC30 ish build, and another Toneslut OT that will be used at some point.

[dotyduke]

Mark, maybe PM Glen (geetarpicker) about the differances... I understand that when he built his two clones he went with the Pacific trannys because thats whats in his original Wreck... But I think he also played around with a clone that someone else built that used the Heyboers. Or Allyn, he'd know...

I've only used the Heyboer iron... The build Paul Ruby made for me had the original 5.2K OT that Doug Holt sold, and the one I built for myself used the Toneslut iron with the 6.6K tap. Both sound fine and any differance could be any of a million little things.

I have a 4.2K Schumaker OT that I'll use for a Rocket/AC30 ish build, and another Toneslut OT that will be used at some point.

That may have been Allyn. I talked to GK last night for about an hour and he sdvised me to call Allyn about the Differences.
MD

[Moose]

Actually, "Pacific" and "Heyboer" are not the only considerations. And I'm partly to blame. I did some early research (my first wreck inspired amp is dated at the beginning of 2003, so REALLY early) and, as we've learned more, I haven't been here as often as I should be to contribute to the evolving knowledge base.

First some history. We started with a heyboer line card that called for M6 steel. There was a lot of debate over the 5200 or 6600 ohm taps as we knew of stancors with 5200 ohm taps and other wrecks had 6600 ohm taps.

Remember, this was when someone had purposely fed bad info, there was a lot of conjecture, and we hadn't seen the real deal in detail, yet. At that point, many of the rumors did not separate Liverpool from Express, even!

At the time, someone was selling the Heyboer iron, and had claimed to have done a lot of research. I promised to reveal nothing of our discussions, so I can't say more about that.

Anyway, he wasn't forthcoming with practical details other than to say the steel wasn't M6 and he had seen 6600 ohm taps personally. He also claimed that the lower grade steel sounded better. We later learned the M6 linecard WAS KFs, but read in a published interview that he spec'd the steel for some hi-fi project he was interested in.

So, we had a bunch of info that said:

1. We'd seen 5200 and 6600 ohm taps
2. The steel is NOT M6
3. We were darned sure the trannies were stancor style
4. The current vendor refused to sell trannies anymore.

We couldn't decide what was best, but needed to press forward. So, I did a group buy and spec'd the OT iron to M27, dual tap with 6600/5200 to satisfy all claimants.

I've been selling Heyboer, since.

We later learned a lot. We got information from good sources on KFs preferred steel, and of course we got fantastic pictures of Franchesca thanks to Allyn, Greg, Glen Kuykendall, and all those crazy cats.

After Glen and RHinson and a couple of other people did some experimenting, including Glen playing the real thing against some other extremely detailed builds, we learned that the original Pacific equipped Express amps were using M19/26 steel and that there was a difference in the feel of the amp compared to M6 or M27 steel.

I have since started carrying M19/26 steel and have distributed about 50 trannies with this compound to get feedback.

So there are now three considerations, in order of importance:

1. Steel type
2. Primary
3. Winder

I believe that numbers 1 and 2 are by far the significant factors. KF used a boatload of tranny winders, and usually stuck to the off-the-shelf designs he began with (thus the use of dynaco for rockets, stancor for early express/liverpool amps). Pacific just satisfied the greatest number of later express amps after stancor went out of business.


Anyway, back to the differences.

Getting a standard tranny from me on M27 will give you an amp that's slightly crunchier, has more top and bottom, and has a different and more aggressive feel.

Getting one of my Vintage Spec trannies (single tap 6600 for express, on M19/26 steel) or a Pacific OT will sound smoother, give less top and bottom, less crunch, but trades that off for the sustain and the singing into harmonics that is so cool in an express amp.

The vintage spec FEELS different when you play. What the pick attack produces, what your left hand needs to do with vibrato to generate sustain, and all that subtle touchy stuff are palpably different, even if the recorded tone isn't really that different.

There's no practical difference between my Vintage spec tranny and the Pacific tranny except the color of the endbell. I've been told by some good ears they can't hear a difference, though I haven't done a blind study or anything. I know the Pacifics are very high quality, wound the same way, and expect them to perform brilliantly, as well.

I'm actually realigning my stock and I won't carry the 5200/6600 on M27 next year as a regular item -- only keeping a few for the folks who have a stated preference for them.

I'll have M19/26 in either 6600 for expresses (my current vintage spec, like the Pacifics), and I'll add a 5200/4300 dual tap on M19/26.

The express tranny suits my preferences, and by going 5200/4300 on the dual tap we've still got a fantastic Liverpool tranny, but that tranny becomes more versatile. Folks can use it for liverpool amps or experimenting with any quad 6v6/el84 setup like an AC30 or 36 watter.

That's going to confuse things a little more, so I hope my brief history helps.

[rooster]

Chris - Wow, a man possessed. Good call on the 6600 single tap and the change in steel. When you get the Rocket iron in house, let me know? I am still thinking a single tap is my preference but I would still try it.

[Fischerman]

Getting a standard tranny from me on M27 will give you an amp that's slightly crunchier, has more top and bottom, and has a different and more aggressive feel.

Getting one of my Vintage Spec trannies (single tap 6600 for express, on M19/26 steel) or a Pacific OT will sound smoother, give less top and bottom, less crunch, but trades that off for the sustain and the singing into harmonics that is so cool in an express amp.

I have the dual tap 6600/5200 and I always felt my amp was too aggressive, too crunchy, too scooped, wasn't smooth enough, and didn't sustain enough. It's probably other stuff too but it's interesting that you pretty much nailed what my amp sounds like and where I'd like it to go.

Just a curiosity question but does anybody know how different these are from a JTM45 OT? Those have a 6600 primary (among others) and I know they're wound differently (seperate secondary windings for one...multiple primaries...etc.) but has anybody tried a JTM45 OT with an Express?

[fishy]

I'm in the same place as Fischerman.
My build just lacks the character I expected from the amp.
Its not bad, kind of as described in the earlier post.
I am certainly intrigued to put the vintage spec into it.

Thank s for the info Chris.

[Richie]

I think either are good. I've used both,and NOS and others.
I like the Pacific OTs and the Moose Heyboer PT. I like the Stancor 3801,which are getting hard to find and pricey....
And the old Motorola 1949 that is in the Trex. It was very smooth with singing susuatin. But finding another is like finding a needle in a haystack.
We've seen some other transformers in a few real wrecks that were different. As for the other models like rocket the A470 dynaco, or bob hinson tranny is good. the liverpool i used pacific OT..

[2tone]

I thought the output trannies on the Express and Liverpool were the same, whether Pacific or Stancor..

[Mark]

Dear Richie and Moose

Very good replies.

[Jackie Treehorn]

I've only used the Heyboer iron... The build Paul Ruby made for me had the original 5.2K OT that Doug Holt sold, and the one I built for myself used the Toneslut iron with the 6.6K tap. Both sound fine and any differance could be any of a million little things.

I bought my original transformer from Doug Holt, too, back in July/August 2003. It's a heyboer marked 11415 TW-OT. The interesting thing is that's the same part number Pacific uses, I believe. Also, I measured it and it's a 6.6k although for a long time I had thought Doug Holt sold 5.2k's. Do you know the model number of that transformer in your amp? It would be interesting to document all the different transformers that have been sold as trainwreck replacements.

My understanding of the chronology of the transformers is the originals had the Stancor, then there was the Pacific copy of the Stancor, and then I suspect a Heyboer copy of the Pacific. Is that correct?

[Moose]

My understanding of the chronology of the transformers is the originals had the Stancor, then there was the Pacific copy of the Stancor, and then I suspect a Heyboer copy of the Pacific. Is that correct?

Maybe. I think the more correct way to express it would be Heyboer and Pacific both copied the Stancors. And KF claimed to have used others, though I understand that most later era Express amps have Pacific, so he probably bought a goodly batch of them.


As for Doug Holt and 5200/6600, I can't comment on specifics. But, from your experience, you can understand why we were all so confused 5 years ago!

I like the Stancor 3801,which are getting hard to find and pricey....

I really wish I'd snagged some iron a couple of years ago when they were relatively cheap. Sometimes old iron sounds SOOOOOO good.

Live and learn!