Yamaha NS-A636 Review
Driver complement: - 3/4" dome type tweeter - 4" ferro-fluid cooled midrange - 8" woofer
Specs: - Sensitivity: 91 dB @ 1 W/1 m - Frequency response: 90 hz - 20 kHz (-3 dB) - Nominal impedance: 8 ohm - Amplifier power: 10-140 W - Dimensions: 13.2" H x 10.5" W x 12.5" D - Weight: 17 lbs with packaging
Midrange sounds reasonably good and clear. Perhaps I am overprasing the midrange because it easily sounds the best of the frequency range.
Treble is somewhat recessed. Not terrible, and overall the middle + high frequencies are quite pleasant, but listening closely I do notice a relative strength of midrange compared to high frequencies. Perhaps this has to do with midrange being exaggerated rather than high frequencies being lacking.
The amount of bass is meager. Despite an 8" woofer the speakers are rated only to 90 hz. Whatever bass is there is not deep at all. It largely sounds like low-frequency noise than pleasant depth to the music.
Even at neutral EQ and moderate volumes the bass is distorted. It is plainly obvious that some bass exists but it's mostly an acoustic mess of waffling woofer cone rather than anything with definition.
Turning the bass up via the equalizer only increases the distortion without adding depth or presence.
There are some tracks that sound OK bass-wise. These seem to have tighter bass that doesn't extend very low in the frequency range and good recording quality. So, perhaps the woofer does decently well in the bass department as long as it has to move a small amount and not too frequently.
I can see why some people in the reviews turn up the low and high frequencies of these speakers. The midrange is definitely way more present than the ends of the spectrum. But turning up the ends on the EQ, while perhaps balancing the SPL across the spectrum, does not really improve quality - highs blend into a constant whoosh and the lows blend into a constant hum.
Maybe these speakers would do decently with another woofer, or perhaps crossing them at high enough frequency where their woofer doesn't do much and using a subwoofer for the entire low frequency range? There are much better bookshelf options out there though, for example the Sony SS-CS5 are better than this speaker in every regard.
I got these speakers as a package deal with a Yamaha receiver (HTR-3064), and I noticed the receiver had the bass turned up all the way to +10 dB as well as I believe the treble was up +6 dB or so. This matches the EQ curves referenced in the reviews of this speaker (by both people who liked it as well as people who disliked it and expressed contempt for said EQ curve).