Opinions welome! Various OTs for the Express

[Jackie Treehorn]

I would guess that it was excluded because Ken felt it would be an improvement to not have the unused tap. Lots of guys say that the 16 ohm tap sounds best because you're using the whole wind of the secondary.

[rp]

BTW was reading up on dyi hifi this weekend. Turns out Heyboer made the original iron for the Harman Kardon Citation II. That's a big deal. In the vintage hifi world the most renowned and sophisticated OTs of their day and maybe all time were the ones developed for the Marantz 8b, the Macintosh unity coupled bi-trifilar, The Quad 2, and the Citation ones. I always liked the Heyboers' sound in guitar amps, and their accommodating service and fast turn around. Knowing more about their history lends even more cred.

BTW, no damn wonder their Hiwatt Partridge OTs are supposedly so fine. They know what they're doing.

[Jackie Treehorn]

Interesting, I did not know that. I asked Heyboer once if they could do a Mac style trifilar and they told me no. That's perspective, though, any push pull transformer will work for a wreck. Compare that to a McIntosh. Even the original company couldn't do the mc290, the reissue is a bifilar design.

I wonder if Ken sought out Heyboer because of that connection. Microscopically perfect is apparently how Ken described Heyboer.

[rp]

Interesting, I did not know that. I asked Heyboer once if they could do a Mac style trifilar and they told me no.

Jackie, maybe a Mac clone is out but I bet they could make you the proper PT & 2X OTs for a Citation II. If I had the money I'd love to dive into a project like that.

Here's a digression for you:

http://www.antiqueradios.com/forums/vie ... 3&t=153074

[randalp3000]

ARG,

I was tearing down to move my rig between services in church last week and an older gentleman come up and asked me who built my amp. He asked me if I ever heard of Heyboer, I said yes and he informed me that he designed transformers for them. We were running late and I didn't have time to talk to him and I'm really kicking myself.

I'm hoping I run into him again and can get his contact info. If I do I'll let you guys know.

[rp]

ARG, I'm hoping I run into him again and can get his contact info. If I do I'll let you guys know.

yeh man, he was probably there during the golden age, get his life story. maybe he did the citations.

[rooster]

Rp, "BTW was reading up on dyi hifi this weekend." Do Yourself In?

[Richie]

Ritchie, thank you for checking in, I am very sure you have run down a lot of OTs over the years.

Let me ask you, given the same build, which would you prefer -if you can make a sonic preference - Pacific clone of the Stancor, or the Stancor?

Of the current iron, what are your thoughts on MM in regards to the Express build? In regards to the shootout on the MCI page, I actually like the MM a lot. Do you have a preference in this shootout? Another question, have you tried the MojoTone Heyboer vs. the various Heyboer Express clones out there?

Answer to the first quest would be original stancor. And you have probably heard Glen mention about the differences between the transformers. Or what Ken told him they were or how they sounded. Black or grey bells. But the Pacific is also very good.
The stancors price has gone crazy.
And many would be hard pressed to hear a difference between them. Sometimes its more a feel, along with the sound. Or if you had the same amp,and could switch between transformers,you may notice one blooms or goes into feedback sooner or easier. Or the harmonics . One onote or chords being played.
Or one may sound more smooth on the high end. Or the lows may be more tight sounding. Even the Heyboers are nice too. I do like the Heyboer Power transformer over the Pacific. Some have reported more mechanical vibration on the chassis for the pacific. Although I like the voltage rating more of the Pacific. And all of this is just me, others may be just the opposite.

A lot of times its what people want, or if they want an amp that is closer to an original.. But I think its getting down to splitting hairs. Some may never hear it,some will.
I think people have to train their ears. Its not as much how good you can hear, its how well you know what your listening for.. I haven't used any of the MC or MM. I have heard them in other amps.

I like a lot of the old iron too. But again, you just have to try them and listen. Maybe the old metal they used then was different than now and maybe it effected how it sounds..

The old Motorola,i'd hate to destroy it to have it cloned. But I think the number on it was a Thordarson made transformer. As for the Rocket, the 470 is ok, but I like the pacific better. There are many others out there that also sound good in these amps.
And although the OT is the soul of the amp, there are many things that have to be right before and after the OT. And that is the fun part!

[rooster]

I picked up the black bell cover A3801 and I see it is a different build than what is being made by Heyboer and Pacific. Those trannys have three E-cores, one sandwiched between the two. This tranny has two E-cores, reversed in the center. The size is identical, BTW. I'm also thinking that the Heyboer piece is made from two different steels - M6/M26/M6? I will also assume the Stancor is just one.

So this is significant physically, and I assume sonically different as a result.

Again, I'm asking, how is it folks have set out to duplicate the Stancor and missed the obvious?

[rooster]

Richie, THANK YOU for that info! I will put the Stancor in later tonight and I can't wait to hear it.

I, too, have run into some older output iron that sounds good, all Schumacher and Triad. They were very busy and well respected, too. The Thordarson I have run into has not been so exciting. They say the founder of that company was a genius. However, one thing that I see on some of their trannys is a weld line that joins all the lams. This seems an 'anti-good' idea but then....there it is! But I like that you found something from that company that you like.

The Triad product was used in the early Magnatone amps and overall these trannys are very sweet sounding, IMO. I have read that Stancor and Triad merged at some point but I really don't know the exact history. Chicago was quite the hub of transformer production and still is to some degree. Schumacher, of course, is all Mexican now.

[RJ Guitars]

It's definitely going to take several people to combine all they know to get an overall expert opinion... but everything above is some of the best straight forward contributions I've read here in a while.

There are numerous versions of the Heyboer Wreck output transformers. The output transformes that I sold from them were tagged as the "vintage" style output. They were intended to take some of the edge off the previous versions... it's important to recognize that a large number of the early Wreck clones were made with the older style Heyboers and many of them sounded awesome.

Yes, if you talk with Pacific's engineering folks you can sort through a bunch of the verbal clutter that has fogged up the Wreck transformer scene lately... one funny thing I can add - JM doesn't use the original KF part number transformer sets, he has his own versions as well.

Edcor transformers are probably the most pure HiFi transformer of the bunch. They really don't change their preferred HiFi winding scheme in my custom units... except I did get them to push the wattage ratings a bit. They also always use M6 steel which has it's positive and negative aspects. If I could ask them to experiment with these trannies it would be to listen to the same design using M19 or M29 steel. They are a true mom and pop outfit and have been wonderful to work with but less of a custom shop than either Heyboer or Pacific have been. Of all the output tranny's I've tried in a Wreck circuit these are the most focused. They always win the QC status - their work is stellar from the consistency in their winding to the cosmetic look of them, to the superb way they pack them and ship them... and their prices are great.

I have a couple Stancor A-3801's that I plan to build with someday, including one of the Gray ones. I also have a set of MM Wreck trannies that I got from Colossal.

Thus far the best sounding one I have built with is the Pacific with my part number (I haven't built with the other Pacific part numbers but I expect the same results). I like this tranny mostly because it just sounds so rich and full sounding. It's not the most focused but it has a lot of flavor to it but not muddy sounding at all. I will have to hear the Stancor and MM to really know how they compare... but more than anything else thus far to me, they all sound different. Each one seems to have it's strength and if the rest of the build is done well, you'll find a sweet spot.

YMMV

rj

[rp]

Rp, "BTW was reading up on dyi hifi this weekend." Do Yourself In?

Nah, if it's tubes I can't get enough. I've long learned to compartmentalize the guitar amp nonsense and hifi nonsense into separate parts of my brain, that way they both can be true at the same time.

Keep the OT reports coming.

edit: just caught the typo. haha - now I get it!

[Richie]

The Triads were used in early fenders too, and the ones I have heard that had them sounded very good.

Also look up the cross reference guide. They had many they would cross. Like A Merit for stancor etc.. And too when dealing with older iron, don't discount them. Sometimes you never know,you might try one not knowing how it was used or abused in an amp. it may sound dull lifeless low wattage distorted, for who knows what reason or why.
Sometimes they may measure ok but sound like crap. While another may sound really good. Its probably good to keep a good OT to have something to compare others to.
I think somewhere their was a post about Ken going through many transformers of the same model or type, to find one that he felt sounded good enough to him to use in his amps. I guess similar to listening to a tube. So I guess he had a pile of ones that didn't meet the grade.

[rooster]

All good Richie, and I read that story about Ken choosing particular trannys in the 'Deric stories' I think.

And here's another one from me. I put the Stancor in last night and then got up this morning and started playing it. Now, this wasn't NOS, although I have no idea what amp it was used in or what kind of usage it saw. I do know it has sat on a shelf for the last 10 years. But I digress. When I first starting playing it, it actually didn't sound that good. It distorted too soon and didn't have the volume or clarity I was experiencing with the Moose Heyboer. Haha, I was thinking this was a big mistake. So at this point I pulled V1 (a questionable tungsram) and put in a JJ gold pin 12ax7 (ECC83 MG). The clarity improved a bit but I was still disappointed with the tone and volume. But I kept playing. During this period, I started rotating between the different ohmages of the OT. Not sure if all here would agree, but running an 8 ohm load, the 16 ohm tap brings on significant volume and clarity/presence/treble. The 4 ohm tap reduces volume and adds a bit more distortion. IS THIS SOMETHING YOU GUYS WITH THE STANCOR EXPERIENCE ALSO? The Heyboer did not do this to this degree. Alright, but then, after 15 minutes of play, things started to change. The volume came up and the distortion lessened. After 30 minutes I realized I had a smile on my face and then felt WAY better about the purchase and swap. I can only assume from this that there was some type of settling in process going on.

I've got the amp running right now, guitar unplugged, and just went out to check that 16 ohm tap again, and it's still true, the volume is significantly louder and the tone is brighter. But at least now it is somewhat in the 'too loud' range and the 8 ohm tap's tone and volume seems 'normal'. (On this subject, I remember Glenn saying that Ken told him to try all the selector positions, and considering the impedance mismatch on the primary, this certainly makes a lot of sense.) And, BTW, the taps on the OT read something like .5 ohms, .6-.7, and .8-.9 on my DVM prior to install.

OK, that's where I'm at right now, happy that I did this. The distortion factor, which is maybe better referred to as the harmonic content - to my ear - is very different than the Moose Heyboer. The double stops are noticeably improved, richer to my ear. I would still suggest that the Heyboer had its thing but it just didn't 'fill in the blanks' as well. I am also convinced that this will still improve as the day goes by, as I leave the amp on and revisit it with fresh ears.

P.S. A follow up, after running the new OT for five hours today, the 16 ohm tap is not as loud as it was when I at first fired it up. In fact.....I think I must have the 16 and 4 ohm taps reversed! Ha! Blame this on faded cloth leads maybe and my haste to install this. At any rate, it seems this OT needed to run for a while. Oh, as to my take on it: I'm in heaven. Using no pedals, the tone is extremely inspiring. It's the kind of amp - sound and feel - I have never had before. And I have to add that the controls on the amp seem much more in sync than before, as if treble/mids/bass/presence are sitting better in their range. Go figure.

[rp]

You always need to let everything warm well up, like 30mins before making serious judgments. Though usually if you really hate it right away it's bad sign. I'm rooting against the Stancor, pro Pacific or Heyboer. Only because if you LOVE the Stancor hundreds (thousands, millions!) will read about it and bid then into unobtanium, and I've already got a long list of parts I failed to stock up on when they were easy and cheap. So, the Stancor sucks, right?