MTS Transformer Upgrades are here!

[okstrat]

I'm still curious though - these amps have been around for awhile, how many 'dead power transformers' are out there. Output transformers go out more IMHO because you can kill them by misadventure. We all know excess heat can kill components, but a lot of the classic amps we know and love had parts WAY under spec - it was part of their tone.

I still think a filament transformer would take stress off the power supply and make it run cooler too, but since I haven't had a lick of trouble with any of my MTS amps (2 RM100s, RM50, 2 RM20s, RT2/50 and RM4) I'm not going to install one either. Totally agree that Mercurys are seen generally as a tonal upgrade over Hammond (don't tell Kevin O'Connor that though!) but I don't think filament transformers are going to make a **** bit of difference whether you use Mercury, Hammond or whatever. All the filament transformer does is heat up your tubes - no signal passes through it, as long as the transformer can supply power to the tubes to light up the heaters and keep it steady, it's not going to matter.

Mercury transformers are not snake oil, they will change the tone of the amp for sure. One might be able to get the changes they want though by modding modules OR modding the amp itself with component changes, and then transformers. The fact that you need to mod the chassis a bit to make the transformers fit sucks though, it should be a bolt in install, and this is going to sour a lot of people on doing it. Who wants to drill holes in their amp? I'm surprised Mercury is doing a custom transformer set for this amp and they can't make them the same size. It's not like our amps have puny little transformers, that's the main reason our amps weigh ten tons!

Also, as long as the power transformer is keeping a steady voltage to the amp, what tonal difference is there going to be if it is hot? As long as the voltage is steady, there shouldn't be any. Of course, the output transformer is a different story.

One other thing - are the custom transformers set up with the same color wires for easier install? Other than having to drill new mounting holes, are there any other issues with putting them in?

Pete

 

[Soulinsane]

The wires are the same colors as the stock RM100, plus each transformer comes with a diagram showing what each wire is for. Makes it look really easy at first lol. The MM's are larger than the stock set because they are designed with more iron and copper. I took careful measurements to insure the new set would be made to fit without problems. Drilling new holes does suck because you also have to remove a few boards. The RM100 takes more work and attention to detail than most other amps since everything is packed so close together. I thought about designing an locking swivel base adapter for the RM100 upgrade kit to allow transformer turning after complete installation but it's only an ideal so far. It would also make the whole install faster and much easier. You would remove the old trannys, bolt the adapters in their place, bolt the upgrade trannys to the adapter, and connect the wires. No boards removed and no chassis modification. I can definitely see the install process scaring some people but it should to some degree. I have had people change their minds about other DIY installs and bring amps to me after they open them up.

A hot PT will be less conductive and waste even more energy to compensate. It is possible to reduce copper lose and increase efficiency by building a transformer correctly with good materials but most places don't care about quality so long as it just works. A bad PT will heat up, choke power, and sound dark. Tubes amps are not the most efficient things in the world to begin with so every once of energy you can save counts. There are times when you might want to starve power to curtain components ( lowered voltage to preamp plates are a key to the brown sound ) but other parts need all the stability they can get. I agree that there are also amps that by freak accident sound great when curtain parts are over stressed. There are accidents in the winding process of some transformers that cause them to sound better than others. One thing I like about MM is they document those "accidents" they find in legendary amp transformers and make them standard in their units.

I also like to modify components in an amp ( or module ) to polish the tone. Its normally cheaper than replacing transformers, I agree, but in the end amounts to more work after test after test. Its the best way to go about things if you don't have a lot of money to throw at an amp though. You do some nice work from what I have heard and seen on this forum. I just wanted to start some where different for once. Try a different PT some time in an amp and see if it makes a difference. Its worth testing at the very least and you will see I speak the truth. I'm not sure how many PT failures there have been with the MTS, but I would think the first generation amps might be reaching the end of their ropes if they operated at the same temperature mine did. Only Randall service could give us the news on transformer failures. Again, I might have had a defective tranny set but I couldn't be sure with out another RM100 to compare temperature with.

A common thing I do hear is how dark the MTS sounds... remember how a hot tranny will cause a amp to sound dark and muddy? I think it has a little to do with the power supply filter caps but more with the trannys if they run hot.

 

[okstrat]

I think it's great that you and MM have a transformer set for our amps, I just thought it was a bit alarmist to say that the power transformers are going to blow in our amps when it's not a documented problem.

I'm a big poster boy for modding these amps - duh! But I never tell anyone that the stock Randall modules or amps are going to self destruct or are built poorly. Here's the thing - the stock Randall amps are built to a price point. And within that price point they are great.

Personally, if I was going to do a MM upgrade, I'd probably start with the output transformer and go from there, because that's where you are going to get the most 'bang for the buck'.

Pete