Need OT specs for 5F6A Bassman

[srv]

Please help, need OT specs to have a transformer made for my Bassman clone project for me and my friend. It would be great if someone had exact specs, but if not I'll take the closest 6L6 pushpull thing possible... I need core dimensions, wire thickness, number of turns, style of winding (interleaving or not) etc.... please help, and thanks in advance! I know it would be much easier to buy one if only I lived in the USA. Sadly, I don't and expensive shipping+customs fee/duty+tax is just too much... I know a small company over here that makes custom order transformers, just the specs would be great! Thanks a million!

[mlp-mx6]

Why do you need to special order a transformer that is already widely available? (Just curious, not disparaging in any way.)

[srv]

It's not widely available in my country and importing it from USA would be too expensive considering I need at least two, if not more (when my friends heard I was making a Bassman, now they all want one). I know it's not trivial to make a good OT but then again, it shouldn't be magic and rocket science, if done by professionals according to correct specs, right?

[flood]

i'd be interested in this too; i live in india, and between the exchange rate, freight and the customs (both the duties as well as the red tape you have to g through) make importing from the US a no-no. i'm assuming we're looking at about 8k CT 50W or thereabouts?

i really want to do a 5F6A sometime; love the bassman sound, know a transformer winder who will manufacture to my specs and last but not least - i have a few possibly used 5881s (brown base, look EXACTLY like the tung-sols but are labelled arcturus and have side getters lying around... any idea if they're worth much?

SRV, what part of the world are you from?

[flood]

another somewhat related question - is it possible to use 6L6GCs in push-pull at LESS than 25W? 275-0-275 200mA secondaries on the PT. 8k CT on the OT. i would like to do a 5B6 bassman before i move on to the 5F6A and other 50W circuits... i would basically want to scale down the power stage to take the trannies i already have, and use 6V6s or 6L6s (i have a bunch of old GBs as well as the RCA metal can ones).

also, how would these sound in a 5F6 in place of the 5881s?

[tubeswell]

The traditional 5F6A Push-Pull OT has a 4k to 4k2 pri-zed and a 2R secondary and is rated for 50W. That's all you need to know to tell your winder. If they don't know what to do with that info, then go somewhere else.

FWIW it would pay to get multiple secondary taps if you are going to get an OT wound up especially anyway (like 2, 4, 8 and 16R) YMMV

[flood]

from : http://www.300guitars.com/2009/09/fende ... or-guitar/

"Let’s take a look at the output transformer. This was a costly and unique design for a guitar amplifier back in the 1950s. First of all it has a 2 ohm secondary which is an unusual output impedance. Why did Leo wire the 4, 8 ohm 10″ speakers in parallel for 2 ohms and not series-parallel for 8 ohms? 8 ohm transformers were much more common and probably cheaper. My theory is that the underpowered Jensen speakers of the time had a high failure rate as bands played louder. Leo may have thought that if a series-parallel arrangement was used then if one speaker failed it would silence the one it’s connected to thus only having 2 out of 4×10’s functional, plus doubling the speaker load to 16 ohms. This 2 ohm output transformer is also an interleaved design. Volumes could be written on transformers so we will not delve deeper into this at the moment. We’ll leave that to Sergio over at Mercury Magnetics."

[Andy Le Blanc]

If its a 4k/2, that's 2000/1 impedance ratio 44.7/1 turns

you should be able to make some educated guess by the outside dimension.
but specifics about the winding, lamination, and gaping I dont have.

[M Fowler]

Flood take a look at my post on the 5B6 I built for information.

http://ampgarage.com/forum/viewtopic.ph ... ght=#97393


Mark

[Structo]

You guys that don't live in the USA need to put your location in your profile so when you ask a question we don't have to be mind readers about availability of a product for you.

Nobody knows if you live in Europe the first time you post unless you state that and it is much simpler to put it in your profile so everybody can see without guessing where it is you live.

[mlp-mx6]

In the first post he stated that he is not in the USA. Does not say where is *is*, only where he is not.

[Structo]

I know, it's just a pet peeve I have.
Sometimes people will offer suggestions only to find out later in the thread that the OP lives in Kazakhstan.

[flood]

...in Kazakhstan.

IS NAICE! I LIKE!

[img:369:297]http://animalnewyork.com/wp-content/upl ... 770131.jpg[/img]

[C Moore]

I know, it's just a pet peeve I have.
Sometimes people will offer suggestions only to find out later in the thread that the OP lives in Kazakhstan.

I have the same compulsion. In addition, it allows us to offer help/aid to guys who may live very close by. I have often helped/been helped by people who live near me. When somebody needs to buy or borrow something in a hurry, it makes it easy to help when you know somebody's proximity.
That's All.....

[tribi9]

Just edited my profile. Now you all know I'm a Canuck!