You will want an amp with an audiofile footprint moreso than an amp built for PA/sound system duty. Something fast with a bit of headroom for bass transients.

Haflers fill this bill nicely. Used Crown DC150. Old Phase Linear 400. SAE. A nice older Yamaha .

Is using a vintage amplifier going to give me a different sound? Compared to a modern one?

These amps I mentioned are all audiofile level amps. They will faithfully reproduce ALL of the frequencies at power and will give your monitors a chance to exhibit their responses in a clean and accurate way.

I mention these simply because you can usually buy them cheaper than new and if they havent seen abuse then they become a bargain. Todays amps arent as good sounding to me. A lot of manufacturers cut corners and fudge specs to meet some sort of competitive level.

This isnt true with all, but a lot especially at a budget price point.

Bryston's got a twenty year transferable warranty. (I think there are minor conditions)
I have a 4B-ST, 250-300 watts or so per channel. Dual mono design, and toroidal transformers, XLR,TRS, and RCA inputs, with input sensitivity adjustment on the "Pro" models, Rack or not, ground lift.
I bought it broken, from ebay, (not purposely!) and they (Bryston) happily repaired it for me, at no charge. (I had to buy ($50) an original shipping carton from them before I could send'er in) I think it sounds pretty good for the price, and they're known for transparency and bass control, among other things.
By the way, I'm not a studio engineer, just a dude with a love for music, and a killer system to listen to/make it on. FWIW.

Mazz wrote: Bryston's got a twenty year transferable warranty. (I think there are minor conditions)
I have a 4B-ST, 250-300 watts or so per channel. Dual mono design, and toroidal transformers, XLR,TRS, and RCA inputs, with input sensitivity adjustment on the "Pro" models, Rack or not, ground lift.
I bought it broken, from ebay, (not purposely!) and they (Bryston) happily repaired it for me, at no charge. (I had to buy ($50) an original shipping carton from them before I could send'er in) I think it sounds pretty good for the price, and they're known for transparency and bass control, among other things.
By the way, I'm not a studio engineer, just a dude with a love for music, and a killer system to listen to/make it on. FWIW.

This is a very lucky and also very very rare find.

If this was a continuously possible scenario, I would spend 24 hours a day on ebay waiting....waiting....waiting....

I thought this was a good thread to tack this onto.

A good friend and former bandmate called the other day when he found a functional Nakamichi PA-7 amplifier at the local Goodwill for $4.50 !!!

HEADLINES - Local Goodwill Stores Under Attack!

And, in other news, audio professionals across the state have been seen running in the streets, giggling hysterically, clutching what seems to be, used, vintage audio equipment. It is still too soon to verify the exact cause of the commotion, but sources point to a local musician, who has been seen rockin' the house, on several occasions.

He is believed to be in cohorts with other local musicians, sources say. We will bring you more, as the story unfolds, but until then, for your safety, avoid standing near entrances, or exits of local Goodwill stores, as this seems to be where most of the recent events are happening.

i have an old macintosh mc 250. its been continually serviced (by macintosh) over the years. anyone have a reason why it WOULDNT be a good monitor amp? i prefer passive monitors.