Speaker-Amp pairing
Toot-toot, the main train is coming to the station ...
I promised this, so here goes. It is a long and possibly boring post.
Speakers for the ears/room/soul
- be open to both stand mounts and towers
- listen and be absolutely convinced about their sound signature
- if your listening preference is easy going, choose speakers with neutral/warm sound
- if you are a foot tapper, headbanger, a neutral/lively/bright sound may be the match
- if available study the frequency/impedance/phase response curves
- ask questions if you don't understand what they mean for real world
- if the room is small-ish and/or budget is tight, choose stand mounts
- depending on budget, decide 2-way or 3-way (these have 2 or 3 active drivers)
- if considering towers, anything with passive radiators should be last choice
- passive radiators pose additional room LF issues, over and above their active counterparts
- if you have a large room with ample distance from walls (at least 3 feet) towers are easier to work with
- if possible, choose front ported models over back ported models; sealed is the best for small spaces
- back ported or multi ported models excite the room more intimately
- there is no way you can wish away room interference below say 300-400Hz
- the room may need some "treatment" or "equalization"
- if you think you can manage to sit in front of them for at least 30 mins at moderate level, the search is narrowing
- bass is nice in a demo room; nightmare in your living room
- that guitar lick or violin screech is great in a demo room; in your space they may pierce your ears
- pay attention to vocals rendition (male and female, high pitch and low timbre, main and/or chorus)
- listen to the overall presentation of music, it should be engaging; not just bass or vocals or guitars
- choose 8 ohm nominal impedance; nothing less than 6 ohm
- 4 ohm speakers are hungry beasts, choose at your own peril; amp mating narrows down considerably
- choose something that has an SPL sensitivity of 87/88 dB (or higher)
- choose speakers with smaller cone sizes for a small-ish room
- that 8" LF driver sounds great, but it digs deeper; meaning your room is dealing with more LF energy
- your seating postion will be between 6-10 feet from speaker plane
- speakers will normally be spaced 5-8 feet apart
- factor the above two points with reference to your room
- get stands for stand mounts, please
Amplifiers for your speakers/room/soul
- Class A/B solid state has the widest choice of makes and models (the following points apply mostly to these)
- so pick something that can provide at least, say 50-70W, of clean power (class A/B SS)
- more watts is not always better
- the only true spec is xx Watts/ch over 20Hz-20KHz at 8/4 ohms; others don't give complete picture
- read up on distortion levels at nominal and max power levels
- some manufacturers state peak current per channel; very useful information
- if your listening preference is easy going, choose amps with neutral/warm sound
- if you are a foot tapper, headbanger, a neutral/lively/bright amp may be the match
- check for balanced sound; one part of the frequency spectrum should not overwhelm overall presentation
- choose a make/model that is not known to heat up easily
- Class A and tube amps are exempted from the above criteria
- good class A and A/B amps will have "wazan"; bigger (better?) transformers, heat sinks
- class D amps are usually lighter so are exempt from weight criteria
- if possible and budget allows, look at amps that can drive 4 ohm speakers
- remote/tone/balance controls are nice to have
- remote for convenience, tone/balance because our ears/speakers/rooms/content are not perfect
- in today's age having digital inputs (DAC integrated) is a good thing
- DAC sonic signature is highly subjective though; much more subjective than amp/speaker signature
In the above recipe book or smorgasbord, "room/space" has been mentioned at least a dozen times.
So lets address the elephant in the room.
The room is the elephant!!
It is like that unwanted 3rd partner in a threesome, and you didn't want a threesome in the first place.
Literally "kabaab mein haddi"
Here I'll repeat this again, at the risk of sounding like a broken record.
Fix your budget for speakers + amp. Max deviation is 10% over.
Plan for other components, if you don't have them, viz., source, streaming service costs (including internet)
Pairing mistake 1
A pair of towers driven by an IA or AVR in a demo room.
Oh they sound just fantastic; I like the sound and I can actually afford them. Yippee!!
An AVR is very tricky; lots of room correction and PEQ may be in effect.
Also demo rooms are very well appointed in terms of room treatment.
Check if you can afford the IA too and possibly the source as well?

Is the demo room approximately the same size as your listening space.
Can the speakers be placed/positioned in an approximately similar arrangement.
You can't do any room treatment (living rooms can't have mattress on walls, etc ..).
You may have to consider some sort of DSP element (more monies and effort).
The pickle jar is getting bigger now; rethink.
Pairing mistake 2
Hungry speakers (FS or BS) with "dingleberry" amp. Yes this happens quite often than you think.
Nothing wrong with the amp itself, but it can't drive them multi LF + MF + tweeters.
It cannot provide the desired SPL without distorting or clipping.
Clipping is dangerous; it can fry tweeters.
You try to push the volume higher, and it just gets muddled and noisy.
Amp needs an upgrade (more monies) or drop the speaker choice.
4 ohm speakers with low SPL ratings are the worst; you know why?
They can kill amps and commit suicide too.
Pairing mistake 3
Actually this is not amp-speaker pairing, this is room-speaker collusion.
Sticking FS/BS near walls and praying that LF issues, boom or muddiness will disappear.
May be if I get that amp or this DAC or whatnot. You suffocate speakers, they will voice out their frustration.
Throwing expensive electronics at a physics problem is not a solution.
Room treatment, DSP. Can you go down this route?

FYI, in my setup there are no real side walls; left is open, right has a stub wall (so yes a corner)
Once when I was doing some cleaning thought I'll move the entire setup about 6" to 8" to the right.
Guess what, my wife complained that the sound is all screwed up; and it was actually.
If stand-mounts can exhibit such Jekyll-Hyde behavior, imagine multi-ported towers.
I can't do room treatment; DSP sounds very complicated and intimidating to me.
Pairing mistake 4
You bought cute speakers. They are small, sexy looking and smell good.
You have a large room and you sit 8-10 feet away. Your amp is a beast. What went wrong here?
Hmmm ... the small cones/drivers can only energize the room to an extant.
You can't beat physics, at least not in this known universe.
If you are a guy who loves bass, you will need a subwoofer (more monies and real estate)
Pairing mistake 5
You have the perfect sound + the amp too. In the demo room it sounded great.
A bit of sparkle on the HF. You bring them home. And they howl at you.
Bright speakers + bright amp. You will need something to absorb the HF energy.
Good luck trying to convince HM to have thicker drapes or drapes on the wall.
Don't even try to suggest furniture change; you'll be homeless

Pairing mistake 6
Warm speakers with warm amp. Sounded OK in demo room.
In your house it may just sound dull; may not engage you at all.
Pairing mistake 7
Dealer or someone says this combo is great for abc, xyz genre.
If you don't listen to these genres, walk away. If you do, think again
Are you gonna be listening to only those genres and a set of 20 artists?
The system is supposed to entertain you; not the other way around.
And how they heck does the amp or system know music genres?
It should play anything decently recorded from a half a decent source reasonably well.
Pairing mistake 8
Amp and speakers with or in room is great. Laboriously worked out placement/position, room coupling, etc.
The source and content plays truant. Yes this happens.
DACs and/or badly remastered content will land you here.
Enter the humble tone controls; does your amp have these?
If yes, use them to the hilt; don't be shy.
Well ... the above are some of the common surprises/shocks that pop in this hobby.
Even seasoned players in the game can be upended every once in a while.
I have had my share of issues with every one of the above and with every change.
But luckily I have built my system over years and done incremental changes.
Not lost any money or fun or gotten frustrated. Work with your gear and room.
Personally, I choose components that allow for tweaking the sound signature.
This is again very subjective; some folks don't like fiddling knobs or controls.
Also, when I go in for something, I set realistic expectations.
I'll pause for now. Maybe others can chime in. In humility, will not hijack the thread
Cheers,
Raghu