Upgrade MojoTone to Mercury Magnetics?

[Jim C]

What do you think the word "attest" means? It doesn't mean I "think" or I "imagine". It means direct experience.

Not to this crowd

 

[coreyfyfe]

Mojotone transformers are wound by Heyboer. Generally heyboer makes a good product, but what you're getting really depends on the design. Compared to Mercury in my experience heyboer is almost always a cheaper option, not sure about with the added markup for mojotone.

I've used both Mercury and heyboer in my own builds and repairs. Usually preference goes to whomever has what I need at a reasonable price and timeframe. I wouldn't swap out one for the other unless I was looking to burn some cash.

 

[KenD]

Mojotone transformers are wound by Heyboer. Generally heyboer makes a good product, but what you're getting really depends on the design. Compared to Mercury in my experience heyboer is almost always a cheaper option, not sure about with the added markup for mojotone.

I've used both Mercury and heyboer in my own builds and repairs. Usually preference goes to whomever has what I need at a reasonable price and timeframe. I wouldn't swap out one for the other unless I was looking to burn some cash.

My experience from building a few tubed audio amps is that magnetics can make a difference. I would upgrade in this order of priority:

1. Output: In my experience a better quality OPT produces a very noticeable improvement in the tonal output of the amp. Larger soundscape in 3 dimensions and better extension at both ends of the frequency spectrum. Whether that is desirable in a vintage guitar amp is another debate for another day - i.e. it may produce something other than "vintage tone".
2. Choke: better quality and more Henries does improve the sound but not nearly as noticeably as the OPT.
3. If the Power Transformer meets the specs required for the circuit and tubes in question this is the last place I would spend money on an upgrade.

 

[agedhorse]

Note that YOUR tone goals may be entirely different. I go through this all the time… better, worse, no different or just a little different. Get 5 players in a room and you will get 10 different opinions, all of them believing that theirs is the only correct answer.

 

[dponbass]

I like Mojotone stuff, namely their Precision 70s pickups, but no experience with Mercury or changing amp parts. It sounds like you are looking for opinons, I trust Mojotone for what its worth.

 

[Wasnex]

I regret "trying" to ask anything.

I believe Mojotone transformers are made by Heyboer.

Mercury Mags are generally more expensive. Which sounds best can vary by user taste and the model of amp you are talking about. AFAIK, these companies basically measure and/or tear down a transformer to determine the specs. Transformers are not precision made, so the original transformers in two otherwise identical amps may perform a bit different. Whichever company models the better sounding transformer will likely sound best.

Although I did some research on these companies, the only practical experience I have is replacing one power transformer. I bought a 69 SVT that was running a Mercury Mags PT. Unfortunately the PT was designed for 6550 based amps and my 69 runs 6146 tubes, which require a lower voltage screen tap. This is something I learned after receiving the amp. I did some research and eventually had Heyboer wind a custom transformer for me. I am sure Mercury Mags would have wound a custom transformer as well, although it would have cost more.

The 69 SVT sounds way better with the Heyboer...because it's the correct design for the amp. I will say that I believe the wire used in the Mercury Mags cable leads seemed to be a bit heavier. However, I don't think this necessarily impacts the gauge of wire used in the windings. I wouldn't hesitate to install the Mercury Mags in my 87 SVT if the original PT ever blows. I am not in the least tempted to install the Mercury Mags unless the original fails.

I have one or more amps still running Mercury Mags, although I did not have anything to do with installing them. Since I did not play the amp with the original transformer I can't say if it sounds better or not. AFAIK it sounds like it should.

If you have an amp running a healthy Mojotone trasformer, I would leave it alone. A Mercury Mags may or may not sound better, but the difference should be pretty small...IMHO certainly no enough to justify the cost of buying and installing a new transformer.

 

[Wasnex]

Whether that is desirable in a vintage guitar amp is another debate for another day - i.e. it may produce something other than "vintage tone".

Exactly. Pretty sure I have read comparison reviews on MM VS Heyboer that got down into these weeds.

 

[Dominic D]

OP, you seriously need to take a step back and understand that the people here WANT to help you. Condescension and ignoring valid request for more info won't help you in any way.

 

[KenD]

OP, you seriously need to take a step back and understand that the people here WANT to help you. Condescension and ignoring valid request for more info won't help you in any way.

A couple of people actually read and comprehended my question and then responded directly to it. Other responders were doing something other than being helpful.

Once again, "attest" necessarily requires first hand experience, not and exposition on what someone thinks or imagines or surmises that they "might" know about something they have never done. I don't need nor want "help" from the latter.

 

[agedhorse]

I have first hand experience with transformers and transformer designs by the hundreds, but even so I wouldn't (and couldn't) "attest" to anything as subjective at the potential differences in tone between transformers.

Tone is not directly impacted to the "quality" of the build. Tone is a subjective perception that can vary with a dozen or more variables. Things like the steel alloy (that can have 30% variations in magnetic properties in a normal production run depending on the alloy and annealing process), insulation variances, winding tension, VPI process, temperature, aging, etc.

It's an art and science to get parts with consistent tone over a large number of production runs.

The other issue with perception and taste is that one player may love what another hates. This means that the same part can be an upgrade to one player while at the same time be a downgrade to another.

This disregards the variations in the hundreds of other components (including tubes and pots) that are also responsible for measurable differences in tone (which may be perceived as positive by one player and negative by another.

This is why you aren't getting a simple yes or no answer… there isn't one. It's not being disrespectful, it's being honest.

 

[beans-on-toast]

Heyboer makes excellent products. Mercury markets their repro products as tone clones. They are different designs.

Another good company is Hammond Mfg..

Classic Transformers

Guitar Replacement Hammond manufactures direct replacement transformers for popular tube amps from Fender, Marshall, Vox, Ampeg, Orange, Gibson, Silvertone and Yorkville / Traynor....

www.hammfg.com

Guitar Amp Replacement Transformers

Keep your classic amplifiers grooving with drop-in power transformers, chokes, and output transformers designed to preserve the original look and tone of vintage amplifier components....

www.hammfg.com

I use Triad and Toroid toroidal power transformers. Engineering support from both companies is excellent.

Power Transformers | Custom Transformers | Triad Magnetics

We have the ability to design a completely custom power transformer or modify an existing standard product for any application. Learn more.

www.triadmagnetics.com

Power Supply Transformers - Toroidal - Toroid Corporation

Toroid offers a variety of standard power supply transformers for single primary, dual primary, solid-state, multi-voltage and power supplies

toroid.com

Which transformer is best depends on the application. There are many options.

 

[KenD]

"Which transformer is best depends on the application. There are many options."

I agree. With no wish to start another eruption, let me put it this way:

If one were interested in this amp, primarily because it hews comparatively closely to the original Fender '59 5F6A circuit, then one might consider the advisability and appropriateness of an upgrade in magnetics and, if so, the Mercury product line comes into consideration.

Link Removed

 

[agedhorse]

Or possibly a downgrade?

 

[abarson]

"Which transformer is best depends on the application. There are many options."

I agree. With no wish to start another eruption, let me put it this way:

If one were interested in this amp, primarily because it hews comparatively closely to the original Fender '59 5F6A circuit, then one might consider the advisability and appropriateness of an upgrade in magnetics and, if so, the Mercury product line comes into consideration.

Link Removed

So is LittleDawg claiming that a Mercury OPT is superior to other makes? I'd want to experience the difference before entrusting my money to the venture.

 

[KenD]

So is LittleDawg claiming that a Mercury OPT is superior to other makes? I'd want to experience the difference before entrusting my money to the venture.

Who said that? No one.

 

[abarson]

Who said that? No one.

Then I don't understand the supposition of an "upgrade" merely on the basis of the name of the manufacturer. Just because it was made by X does not mean that it is "better". What is your definition of "better" and what are you comparing it to?

 

[agedhorse]

Then I don't understand the supposition of an "upgrade" merely on the basis of the name of the manufacturer. Just because it was made by X does not mean that it is "better". What is your definition of "better" and what are you comparing it to?

Correct, like I mentioned earlier it may be perceived by different players as an upgrade, a downgrade, or no preference either way.

 

[KenD]

Then I don't understand the supposition of an "upgrade" merely on the basis of the name of the manufacturer. Just because it was made by X does not mean that it is "better". What is your definition of "better" and what are you comparing it to?

Alas, I am on probation so I must self-edit a more fulsome response, for fear of violating the terms of my probation and incurring further administrative action. I will simply say, therefore, that I decline to engage.

 

[agedhorse]

Perhaps you do not understand HOW subjective this topic is, and why there is no singular answer. Your closed minded, pre-concluded approach may have rubbed a few folks the wrong way.

I spent the last 4 years working on a LOT of audio transformer redesigns with one of the top audio magnetics engineers in the world. Not only did they have to sound as the amp design team wanted, but they also needed to comply with modern safety regulations under the 62368 standard if they were to be sold world wide.

We developed samples where some on the team liked sample A better than sample B, others on the team preferred sample B over A, and some could easily live with both. Who am I to say which sample was an "upgrade" since the results were split?

Since magnetics was not my specialty in school, I had to spend a week reviewing magnetics theory, as well as the design and especially the manufacturing of wound components. What I discovered is that with all of the variables involved, a good chunk of the work involved qualifying the design margins that included tolerances and aging characteristics of the materials, especially important when comparing with a "golden sample" that may be 30 years old.

 

[Jim C]

Andy, can transformers be made the same way as in the 50's or are there materials and/or practices that no longer meet EPA approval?
For that matter, has UL and other sanctioning bodies changed safety regulations / applications that would also potnetialy change tone?