Perfect match for ATC speakers

Depends on your budget and what sound characteristics you’re looking for. 

Well, not to be discouraging, but to be informative:

you've done the opposite of what I advise: try first to find efficient speakers you love, using sensitivity of 90 db as a starting goal.

you bought very inefficient speakers, low sensitivity.

Sensitivity: 85dB @ 1W @ 1metre

LOW sensitivity Speakers need HIGH Powered Amps. That increases the cost, size, weight, heat of required amps. All that reduces placement options. All that makes it harder to try Tubes in the future.

What size space, and what volumes will you be wanting?

If you can, I suggest you return them.


If not: also consider this:

Their specs appear to be honest regarding their limited ability to produce bass:

Frequency Response (-6dB): 56Hz-22kHz

Due to both limiting factors: start with the idea of eventually using a single or pair of self-powered sub(s). And, make sure your preamp or integrated amp has PRE-OUT.

You want to send the bass signals out to another amp, so your primary amp only needs to amplify upper bass, mids, and highs. It can then be lower power, and the speakers will sound better not trying to make low bass. 

Raven says low bass is 65% of the power needs.

" High-Pass Crossover

This addition to the Avian series provides an extraordinary advantage when using a subwoofer. It frees the power amp from 65% of the load it normally has to bear. This is like tripling the power of the amplifier in terms of its ability to drive speakers. It also frees smaller speakers from reproducing low bass frequencies that they really don’t reproduce very well which lowers overall distortion. This is all achieved with a gentle 6db per octave slope making it easy to achieve a seamless transition with a good quality subwoofer."

https://www.ravenaudio.com/product/blackhawk-mk3/

Your Speaker's Full Specs:

Drivers: HF ATC 25mm Neodymium soft dome, Mid/LF ATC 150mm CLD
Matched Response: ±0.5dB
Frequency Response (-6dB): 56Hz-22kHz
Dispersion: ±80° Coherent Horizontal, ±10° Coherent Vertical
Sensitivity: 85dB @ 1W @ 1metre
Max SPL: 108dB
Recommended Power Amplifier:  75 to 300 Watts
Nominal Impedance: 8 Ohm
Crossover Frequency: 2.2kHz
Connectors: Binding Posts/4mm Plugs, bi-wire
Cabinet Dimensions (HxWxD): 381 x 232 x 236mm / 15.00 x 9.21 x 8.46″ (grill adds 28mm depth)
Weight: 10.9kg

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Oh, thanks. Yes, I can return them. So, what do you recommend me? These are my specs:
- Room size: 20x10 ft.- Distance to speakers: 10 ft.
- Music: mostly jazz and classical.- Volume: medium.
Thanks again!

@soix ’s comment is on point

that been said, i would add that in my experience atc’s are very demanding of amps in terms of power as well as tonality - atc’s are ruthlessly revealing and hard to drive (quite inefficient)... their lower tier speakers present an irony in that the speakers may be $1500-2000 a pair but to make them sound really good you need double, triple that in quality of amp to handle

think ultra high grade high power solid state (which can be mucho $$$)

"you’ve done the opposite of what I advise: try first to find efficient speakers you love, using sensitivity of 90 db as a starting goal."

That above statement is BS. Those ATC speakers are outstanding. If you buy a speaker just because of its high efficiency rating you will end up something you most likely won’t like.
Are you looking for a separate amp or an integrated ?
What is your budget?
BTW, my friend has the ATC SCM7 and uses a 60 watt solid state amp with no problem!