Opinions welome! Various OTs for the Express

[rooster]

I have tried the MojoTone OT and the version sold years ago by Moose - both are Heyboer. These both have the sandwich dual type steel laminates that originated in the Stancor OT.

I have not tried the Pacific, the MCI, or the Heyboer version that RJ sells.

Has anybody here swapped iron in their Express builds who would care to comment on the results? I am looking at the saturation thing mainly, but bass content, as well, trying to find one that hangs in a little bit longer than the Moose version that I have.

As to my opinion regarding the MojoTone iron vs. the Moose iron (both Heyboer), I can report that there is a difference in the saturation and tone. To my ear, the MojoTone version sounds different/*clearer* in the bass frequencies, which I like, but does not saturate overall as quickly as I want. Eh, and it's a bit more complicated than that, the difference in the sound of the two Heyboer trannys. However, one thing is certain, the MojoTone iron presents a LOUDER soundstage - something I'm not too excited about.

Plainly, I want something in between. Thanks.

[rp]

Can't help you out, but, if you go all out and buy both the MC, and RJs Pacific, and maybe his Edcor, then you will be the TAG expert on the available Express OTs and you could make a full report that could become a stickie Actually RJ might be the expert, wonder if he ever tried the MC and Mojo?

[rooster]

rp, yes, this has occurred to me. I think the Pacific is calling my name right now.....

Its funny how most of us build an amp and - whatever iron we put in it - we think, eh, this is good, when in fact a change might be dramatic. Well, or subtly dramatic. I'm suddenly thinking that subtle is very important in regards to OTs.

[M Fowler]

I think there has been quite a few of us over the years that have built the Express with different iron brands.

Early days guys were using Hammond. My first Express was a Ceriatone then I built my own using Allynmey chassis and his Pacific iron set.

Next was a Express combo with JTM45 PT and MC 40-18088 40w 6k-2/4/8 OT.

Next was a rj's PCB Express with Edcor transformers.

My final Express was in PCB format using eyelets Martin Manning version using MC Express PT/OT set.

Each has it's own character but none were built with same resistors or caps so not a fair comparison in my mind.

[Drew.12345]

Afternoon,

Well.... This thread inspired me to do an OT swap in my Express this afternoon.
I had the Mercury Magnetics TW-OT (using the 6k6 primary)in there for about the past year and today I swapped it out with RJ's Pacific iron P#25525.
I realize that there is a bit of conversation going around where an apparent Pacific transformer # 11415 was cited as the real deal.
I made a call to Pacific this afternoon and asked to speak with an engineer and asked the differences between the two.
After 5 minutes of the engineer comparing both line cards I was told that the 11415 and RJ's 25525 were identical. +1 for RJ

Back to the comparison.
I found that the MM sounded more focused and had a wider bandwidth (somewhat like an EF86ish compared to a 12ax7) to my ears.
The pacific was a bit darker and smoother in comparison and I ended up leaving it in there as it sounded more like the Express demos that I have heard online.
Nothing wrong with the Mercury iron at all as I really like it as well and I put into another one of my wreckish builds and it still sounds great there.

I play mainly a tele and for me I believe the pacific in my Express is a better match.
I wouldn't say one was definitively better than the other... Just a different flavour....
My Express was putting out 402v on the plates today and was biased at -33v for each test.

Anyway.... Just my $.02

Andrew

[didit]

Mark, you wrote --

My final Express was in PCB format using eyelets Martin Manning version using MC Express PT/OT set.

Any comments specific to Magnetic Components iron?

Thanks .. Ian

[M Fowler]

I like the MC Express iron and would use it again but the PT is much larger then all the other brands.

I got nice darker tones with this Express version plus the addition of the Presonance to add more depth.

I don't think it is correct to say one brand is better then another without viewing components, speaker, guitar and cables used. It would have to be a very controlled test and even then it would be questionable in my mind.

[rooster]

Thanks, Andrew. I realize it's sometimes difficult expressing an opinion of something sonic, so many variables. But I think you told me something I can use. I did want to pursue this though. You didn't talk about saturation. Can you hear/feel/ sense a saturation difference between the Pacific and the MM? Does one distort sooner than the other? And, hard question, does the neck pickup of the Tele, using the Pacific OT, have a similar clarity to it? In other words, did the neck pickup 'washout' more with one vs. the other?

Thanks! Also, what did that MM cost, if you don't mind sharing?

[Drew.12345]

Rooster,
Tying my best to be helpful. these are tough questions

" You didn't talk about saturation. Can you hear/feel/ sense a saturation difference between the Pacific and the MM?"
Saturation... The MM to my ears sounded a bit high fi-ish if that makes sense.
The saturation was more abrupt and harsh to my ears and Really would cut through the mix like a chainsaw in a band situation IMHO. It Sounded good but again more in your face as it was bright and angry. It still sounded great but not like like the Express videos I've seen online. In comparison, I now have the MM in an EL84 trainwreck style amp with just a volume and cut which is where the I took pacific iron out. This amp is now a lot brighter with the MM OT and I have use less cut to try and smooth the saturation out. It would definitely make the amp more useable with humbuckers IMHO.
The Pacific I would say was much smoother and a hair thicker with my single coils. It really sounded more liquid in that it was smooth and thick with great sustain and I did not find it harsh at all.

"Does one distort sooner than the other? "

IMHO I would say that the distortion comes on at the same spot but the MM would give a bit more illusion of distortion coming on quicker as the brightness would be more prominent like adding more presence if that makes sense.

"And, hard question, does the neck pickup of the Tele, using the Pacific OT, have a similar clarity to it? In other words, did the neck pickup 'washout' more with one vs. the other? "
For the record, I don't really use the neck pickup often in my tele.
I did try my Express this morning on the neck pickup to answer this but did not try the MM directly to compare so I'm just going off memory. The pacific didn't really wash out but if it were me I just would add more presence to compensate for the pacific with the neck PU and would be right back in the game.
So given the smoothness of the pacific it would say the controls were a bit more useable as the harshness was not as apparent.

"Thanks! Also, what did that MM cost, if you don't mind sharing?"
I believe I paid about $190 if memory serves me correct. It was a bit of a gamble as I really like Mercury products and still really do.
I really like the MM TW-OT and it's a great fit for my other build so it ended up being a win-win for me.

If I had to do it over again and was building an Express I would just email RJ and get the pacific.

Again, just my $0.02 and hope it helped.

Feel free to PM me if you wish as well if I didn't respond correctly or if you have any q's.

Andrew

[rooster]

Thanks again, Andrew. Yeah the neck pickup thing is a thing for me, not that I hang out with it more than any other pickup, but to me it tells me a lot about the amp - any amp. When you have an amp that can do some magic on a neck pickup, i.e., make it more dynamic/clear/present then you have something. I personally am beginning to think that this is all OT.

MCI has a little OT shootout on their web page that is very interesting. Have you guys seen/heard this? They have the MM, Heyboer, MCI, and Weber brand, as well. Very interesting. Click on 'paper vs. plastic' on the home page. Ha, it's really a shame the Pacific isn't included here!

Here's a question regarding the Heyboer trannys. Does anyone know if the model made for MojoTone vs. the Moose version are identical? I had Phil make a few trannys for me and he seemed really committed to NOT duplicating various company's trannys. Which is to say I suspect there is some difference although they look the same. Here's the numbers: 9960815 (Moose), 9960718 (MojoTone). I will call Phil on Monday, but I was wondering if anybody else has checked this out?

[Richie]

A lot of great current made iron. And a lot of old vintage overlooked iron.

I've tried probably more old than new. And there are many of the old out there. One of the best sounding ones was one I got from an old Motorola hi-fi from 1959. There are many others by Stancor,Thordarson,Merit,Haldarson, and other Chicago made transformers.

[rooster]

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?

[Colossal]

Rooster,

I've built a couple of Expresses with the MM OT and have a Liverpool and an Express on the bench now (personal builds), both of which have MM iron. I have to agree with Drew's assessment of the MM OT sounding hi-fi-ish; in a good way, not implying tinsely sterility. It is very smooth, wide, and clear sounding. I find the lows to be punchy, full, and tight and the highs not at all fatiguing. Of all the reports of Expresses having top end to spare, I found the amp to be well balanced and use/like the 500p bright cap. I definitely preferred the amp with the 6k6 primary, it just had more of everything. The 5k2 had more of a woofy low end, but lost the clear, 3D space of the 6k6 primary. Distortion sounds very even with a nice shimmering quality and excellent separation.

[rooster]

Colossal, hey there, I am glad to hear that you like the MM. In the sound bite, I liked it, sure. And I think what I hear is described by you and Andrew both.

Today I picked up a Stancor OT so it will be the next thing I try in the amp. I have wanted to try one of these from day one so this will resolve a few questions, I'm sure. I'll get back to you on this experience in a few days.

One thing does occur to me and it's a simple thought. If somebody is cloning the older RS OT in early Marshalls, OTs that included a 100 volt tap, and they say that the 100 volt tap makes a difference to the audio, how is it that this never occurred to Ken? When he had Pacific clone the A-3801, why did he skip the taps? Knowing the thoughts he had on wire and caps and tubes, how did this not become an issue? Eh, but maybe I misunderstand his appreciation of the Stancor OT.

Too, it may be that I won't like the Stancor iron as much as I like the Heyboer pieces that I have. In which case, eh, I will stop wondering about this. However, if I do like it better, then I'll come back here and get even more crazy on this subject.

[rooster]

!