Do OT's Break In?

[tweed5259]

I have a question, I put a MM Tone Clone OT in my 5F6-A and I did two recordings with it, and one sounds awesome, it was the first day I installed it, it had a real smoothness to the highs, a singing quality, which it has since seemed to have lost.

There was one time where the speakers became disconected while the amp was on, and I know that's trouble, but it still works, I've just noticed that now it sounds more sterile, not bad, just not as great, like that old vintage amp great, where you can crank the presence, play on the bright channel on 9, and no bass on the dial, with a telecaster and it still sounded smooth and amazing!

can anyone help me get back the tone I've lost? Or do I need a new OT?
thanks.

[mac1amps]

You may have "cooked" your [power] tubes to the degree of losing their high-end "sparkle" (especially if they were new tubes prior to the speaker incident). The transformer upgrade is permanent, PERHAPS unless it is subject to long term "abuse" (such as alot of "dimed-out" use with an attenuator IMO), but even then, it would take alot of abuse to blow-out a Mercury.

[Steve Conner]

There are literally hundreds of factors involved in tone, both real and psychological. I'd strongly recommend blaming something cheaper than the O.T.

[dai h.]

(hopefully this is not your problem, but) one time I had a marshall 50W that had its OT go open on one side of the primary, and it basically sounded very bad after that. Checking for an open is easy, open = zero ohms (no connection). Otherwise (I don't know how this would sound, but) maybe shorted windings are possible?(if the OT was damaged after the open secondary episode). I might check the DCR, and see if it's significantly different (seems usually pretty close but not quite exact). Also, possibly an open connection with a bad solder joint could be possible. At least I'd hope it wasn't actual damage to the OT, since obviously that's an expensive part and a bit of a PITA to replace.

[scole]

hey tweed, what is your plate voltage? what is your bias setting? did the amp lose power as well. tubes break in faster than ot's and cap etc. double check your voltages. it souds like your bias has drifted.

[lmolter]

This may be a bit off-topic, but since the original post mentioned the Mercury Tone Clone OT, I was wondering if these transformers (OT, choke, and PT) are seriously worth the extra money? I'm trying to be true to the original design in the Bassman I'm building. I used pricey caps (Atoms and Vitamin-T's), and I'm getting to the point of purchasing the iron. I can see the benefit of a good OT, but will the PT and choke really have an effect on the tone? And I will accept flames on my choice of caps. I haven't soldered them in yet <grin>.

Larry

[mac1amps]

Over the past couple of years I have upgraded maybe a dozen amps with premium grade O.T.'s and "chokes" (mostly using Mercury's, but some using hi grade Hammond's [the 1600 series, NOT their new "drop-in" replacements] as well). These amps included some [virtually] brand new Dr.Z's, as well as a Vox re-issue, a PV Classic 30, and some SF Fenders (Deluxe, Vibrolux, & (2)[re-built] Bassmans). Each one of the upgrades resulted in a substantial improvement in bass response (REAL Bass response, not just added "fartsy" bass, such as what often results from increasing the value of coupling caps), high-end definition with reduced harshness, improved sustain, and improved touch sensetivity. All of these improvements were evident whether the amp was being used "clean", or driven into heavy clipping. Another nice feature being the added versatility of having a choice of speaker impedance options. I've found the "choke" upgrades to definately be part of the improvement (I upgraded a SF Deluxe of my own, first without the [new] "choke", and later installing an upgrade). With respect to the POWER transformers, there's somewhat of an indirect influence on the overall tone, but I think the main advantage to upgrading power transformers is primarily to assure long-term stability of the amp's operation. Yes, these can be quite "pricey" upgrades, there's no argument there (that's the main reason why I've been trying out the Hammonds-a "poor man's Mercury"). I'd have to say though, that each one of my clients that had this done found the results to be worth every cent (my client with the [4] Dr.Z's, had every one of them upgraded, after hearing the improvement of the first one. FWIW, this is a seasoned studio "session" player).
With all that said, I WILL have to say that I found the results to be less evident with very low power amps (10 Watts or less)

[Chris - CMW amps]

@Mac1amps: +1!

Regarding PT-upgrades: I do experience more note-seperation all else being equal. Depending on the budget most of the time I do start with the OT and choke. Altough iron and speakers do have a very great impact a well tuned/voiced circuit is the start from every amp imho so most of the time I do modify the circuit and an OT/choke-upgrade at least.

@tweed5259
There's some change in OT-tone* (becoming slightly smoother sounding) after some hours playing at (louder) volume but the situation you decribed must be a defect, maybe the OT is broken due to unloaded situation/etc.
Good luck!!!

* don't forget new tubes do also "need" some hours to break in so it's best to use used tubes to hear the OT-sound slightly changing.

[tweed5259]

voltages are normal, amp definitely didn't loose any power, it just doesn't sound as good, I'm going to buy a whole new set of tubes this weekend, hopefully it's just that.