Bryston 2B overhaul advice needed

Hello,
I purchased this 1986 Bryston 2B cheap on eBay. I kind of wish I hadn't... it sounds good, but it has an annoyingly loud mechanical hum coming from the case as soon as it is powered up. Bryston told me that these older power transformers were prone to this, and this is one reason they switched to toroidals.

Does anyone know what it would take to upgrade the transformers to toroidal? i.e. which transformers, and whether I can drop them in without changing other components, etc.
Also, which caps should I buy if I were to do a re-cap? And, there's a couple IC's on the back I/O board - what are they? I'm sure there's better ones available now
And what about transistor replacement, any advice?

It sounds good as is, but I would love to know that it is in top spec since it will be powering the NS10's I mix on.
thanks,
JS

Here's a pic of the insides.

Not trying to be snarky, but have you asked Bryston these questions? I have found them to be extraordinarily helpful with their older products.

You need to know the primary and secondary voltages of the existing transformers to then source a toroidal replacement. Then you'll have to get dimensions and see if they will fit. I am skeptical from the pic you supplied.

Any good Sprague, Panasonic or Nichicon caps will make fine replacements.

Would not do anything with the transistors. I would be suprised if you found anything that was vastly better in that package.

a 4b from the same era manifest 180 VA of core loss,
transformer disconnected from rectifier,, with plenty of the annoying acoustical noise.

you will spend more on parts than the unit is worth, just my opinion.
but there are many power toroids available.

while into the unit, why not take a look at the output stage stability network (or lack of). 
A  Zobel with conventional values of 0.1 uF and 10 ohms, before the inductor, might be a good place to start.
IMHO. bigger improvements there than in capacitors. 

Do you have Doug Self's book on power amps?

Thanks for the replies. Bryston told me that upgrading to toroidals would probably cost $400 if done by them. And I would have to ship the amp.
I don't have Self's book on amps, although I have Small Signal Audio Design, which is great. For other things.
I don't hear hums or buzzes in the speakers, so perhaps re-capping isn't worthwhile?

I was thinking that a good way to know if I can trust what I hear through the amp would be to measure its frequency response. With a line-level processor I usually do that by looping through it with FuzzMeasure. Not sure how I would do that with a speaker-level output, though.

The schematic of 2b (in the attachment)  is identical to the 2BLP version (downloadable at Bryston site) where 100VA 56V to 66Vct power transformers are used. You can ask Bryston for replacement power transformers for 2BLP, it will most probably fit inside your chassis, and DIY. You will need of course to do some mechanical adjustments. Or you can find somewhere else similar transformers, be aware of the small available height in the chassis. 

It took a while to get to it, but based on your advice I installed two Avel Lindberg Y236405 toroidals. I also installed a power switch on the front panel and converted the ¼" headphone jack to an ⅛" jack.
The amp is much, much quieter in the room now. Only problem was the the transformers were slightly large for the case, so the cover is a little high in the middle and is bent over at the sides. I'll accept that for the improvement gained!
JS