Classic 30 replacement transformer (Hammond)

[drycounty71]

I am looking to replace the PT and OT on PV classic 30. Looking for p/n's for Hammond "classic" series. Anyone been down this road already? Thanks for any input in advance.

[vmazz]

I am in no way an expert at any of this. But I did just replace my OT in my champ 12 with an Edcor OT. I highly recommend checking them out ..impressed with the quality( I thinks they are cheaper and better than the hammonds). My OT is as big as my PT now. I am sure they have a suitable replacement for the Classic 30 OT and PT. You will need to now PT necessary stats and OT primary and secondary and I think the classic 30 is a PP with el 84s so you may want them to know that. If you call them they may be able to tell you what they have that is appropriate. Of course if someone here can chime in and give better advice...I just am really impressed with Edcor as others had stated and Im happy to buy made in the USA parts. Good luck.

http://www.edcorusa.com/Products/Default.aspx

[drycounty71]

That is part of my issue, the specs. are extremely difficult to find as far as already posted specs. Mercury Magnetics has what appears to be drop in replacements but too $$$. I saw somewhere on another forum that someone purchased an output transformer from Hammond for their classic 30 and paid somewhere around $40. Anyways, I contacted Angela.com and their response was "Hammond doesn't offer direct replacements for Peavey amps. Contact Peavey directly; they're usually very helpful supporting their products old and new." I already have their transformers, why would I want more??? Anyways, thanks for your post.

[Enzo]

I already have their transformers, why would I want more???

Possibly because you were trying to repair an amp. How would we know?

I can't imagine spending extra $$$ for a fancy power tranny, OTs may be a different thing. FInding a bolt-in for a Peavey C30 might be tough. But we are talking four EL84 down to whatever speaker impedances you desire. So there should be a number of choices available. You will have to figure out a mounting scheme on your own. A quad of EL84 will have about the same impedance anywhere they are. SO transformers made for that should work fine.

[drycounty71]

"Possibly because you were trying to repair an amp. How would we know?"

It was a rhetorical question directed at the statement made by the Angela customer service person. Of course I could contact Peavey and order another part.

So a OT based on 4 x el84's to a 16 ohm/8 ohm is sufficient info for sourcing a new OT? The reason for my asking is I was taken by the fact there seems to be a lot of info for the OT's I am looking at and didn't know which one I needed.

**From Angela.com under Hammond Push-Pull Output Transformers section**

ex.
1645 30W, 5000ct, Ultralinear taps 40%, 4/8/16 ohm, max. DC per side 128mA, 6L6GC, 6V6, 807, 5881, EL34.

I have a 30w amp but my tube type is not listed.

ex.
1609 10W, 10,000 ct, Ultralinear taps 40%, 4/8/16 ohm, max. DC per side 100mA, 6AQ5, 6V6, 6BQ5, EL84.

My tube type is listed but not the wattage range. This confuses me, I don't know what the centertap value is?

[ThermionicScott]

4xEL84 amps usually have an OT with a 4K primary impedance, if that helps.

[Enzo]

1609 10w - looks like 1609 model is a 10 watt transformer.

The impedance with center tap means the plate to plate impedance with specified load on the secondary. Put an 8 ohm load on the 8 ohm tap, and hte tubes will see the rated impedance.

My suggestion of selecting a transformer based upon application - the four EL84 for example - had in mind that it would also be of appropriate power rating. Most tubes will work fine into a range of impedances, as oposed to only one particular impedance. That is why you might see two different transformers intended for a similar application, yet they have differing impedance ratings.

[drycounty71]

I came across this link from another post where a similar question to mine was asked. This looks like it would work

Hammond 50W 2 x EL34 and 4 x EL84/6V6 30W Class A output trans- AWESOME

A great explanation on transformers both Power and Output was discussed at:

What's the deal with big iron transformers? [Archive] - The Gear Page
"What's the deal with big iron transformers?"

[Enzo]

Hey, I see in your sig, you have included Enzomod on your C30. You did the cathode bias conversion? Or what else has my name over there, I forget? Haven;t talked about those in a long while. WHat was your experience doing it and the result?

[drycounty71]

Hey, I see in your sig, you have included Enzomod on your C30.

I performed the cathode-bias mod based on yours/Steves notes, without the adjustable-bias mod portion. I have noticed very little in the way of change to the sound or performance. I appreciate the details of the notes section for the mod. Yours and Steve's notes made the mod easy to perform.

[wizard333]

The MM Classic 30 OT is very expensive.

BUT

The bassman OTs are not nearly as pricey, and work just fine for 4xEL84s. (2x6L6 want to see about the same plate impedance as 4xEL84).

In fact, thats what I put in my C30 and it sounds fine. The main difference you'll hear is ability to continue to sound defined and push low end at higher volumes.

[rudutch]

6L6/EL34 Universal 4.2K 30W Output Transformer Fits Fender Bandmaster, Pro Reverb, Tremolux, Vibrolux, Vibroverb

maybe?

[wizard333]

Biggest bang for the buck mods on a C30 are:

1) 100k mid pot; the stock 25k pot leaves things too scooped.

2) Alter the value of the "boost cap" to something more reasonable than .047. Even .001 and .0022 are pretty gutsy boost cap values (All this does is sub in a larger treble cap), and combined with the 100k mid pot gives a nice non-scooped midrange without the boost and a reasonable boost with the boost engaged.

3) Presence/Resonance controls. The circuits are already there, you just need to sub a pot for the fixed resistor.

The MM bassman OT (which I've used on a lot of amps) is a good mod if you are playing at high volumes and need the low end and overall sound to stay defined. If you are playing at practice volumes, you probably wont hear the difference vs. the stock xformer.

[Bruce / Mission Amps]

6L6/EL34 Universal 4.2K 30W Output Transformer Fits Fender Bandmaster, Pro Reverb, Tremolux, Vibrolux, Vibroverb

maybe?

A bit too small but this one kills with four hot idling cathode biased El84s in VOXY amps:

Tweed Bassman, Concert, 59 Bassman, Super Reverb, Output Transformer 4/8/16ohm

[drycounty71]

Bruce / Mission Amps, I went with the transformer you recommended for the tweed bassman. Too small? This thing dwarfs the factory OT! I haven't made my connections but once I have tested, I will post my thoughts on this for whomever is searching for similar info, to review.