QSC K10 for keyboard (how is the low end?)

I looked at past posts and saw a lot of people screamin about the QSC K series are great for keyboards.

But anyone using a full 88 keys on them? I've read that the low A on a piano goes down to 27Hz and I swooped by guitar center and the low end was listed at 51 Hz I believe for the K12 (they didn't have K10's in stock). Thinking about hooking up a board to one of them in the store.

I've thought about the motion sound but it's too heavy. I don't wanna go heavier than about 30-35 lbs which probably wipes out a lot of choices. I'm willing to spend up to $850.

Just curious if the bottom end of full range of keyboard speaks clearly.

I believe the bottom key of an 88 key piano is 55 Hz.

According to http://www.qscaudio.com/products/speakers/K_Series/series_specifications.php

the K12 is 6 dB down at 52 Hz, so I would not expect it to be flat to 55 (they might have a curve there somewhere)... but most people would not find that to be a dealbreaker.

A0 is 27.5 hz.

Thanks man. I just don't want those low sounds falling off the map and sounding faint.

I'm so close to caving in and buying one.

Hmmmmmm....

I just recounted and realized I had counted from A below middle C for 440, instead of A above middle C, so you're right, thanks.

It would be nice to know the exact frequency response for some of these amps.

I'd be curious to know the dB drops at lower frequencies.

It's not a big deal. Most large PAs can't get anywhere near 27.5 HZ. And I can't think of a song that uses that note on a piano. Synths are a different story as you can have a sub-harmonic that can get that low.

I wouldn't go anything smaller than something with a 10" speaker. At low volume they will do very well. If you want volume, then you will need a sub in addition to a full range speaker to get that low with fidelity. You may want to try a JBL PRX 615. It won't go to 27.5 hz, but it will sound pretty good on a piano voice.

I have a pair of K10's with a PC3X 88 key - lowest piano notes are not bad. The frequency is indeed below 30Hz, but the waveform, even sampling a 9' concert grand, is no where near a sine wave, but is mostly comprised of harmonics. I usually use the K10's gigging with my PC3 (76 key) and use a pair of E-V SxA 100+ in the studio with the PC3X. The EV's are 12" instead of 10".

I debated for several weeks whick K series to get, the 10 or 12. In the end, since I already had a pair of 12's in the EVs, I went with the 10's for lighter weight and easier load in/load out. I also have a pair of EON 15G2 that I leave in a fixed location - but overall they don't sound as good as either the EV or QSC pairs. If I had planned to leave the QSC's in one place most of the time, I would have gone for the 12's.

OTOH, if I were playing key synth bass, I'd probably want either the subwoofer that goes with the K10's, or something with a 15". As it happens (being a bassist also), I have a Trace Elliot bass head with both 2x10 and 1x15 cabinets for the occasions where I really want bass (and am willing to move the heavy and bulky cabinets).

Interesting appreciate the feedback BluesKeys. I'm just worried that some harmonics and undertones would missing and I wouldn't give me that punch I'm looking for (especially for rhode sounds). I have an roland 300gx (36 lbs)and an Electro 3 73 (18 lbs). They're light and easy to move around.

But saying that the QSC sound so good really helps me. I'm stuck between K10's and the K12's mainly because of the lower end. But the extra weight of the K12 is very unappealing. I saw the Ksub at 76 pounds is there something smaller and lighter out there of good quality?

When I need more bottom for left hand bass gigs, I add a Markbass Mini CMD 121P and I'm very happy with it. But I'm only trying to get good "bass guitar" out of it.

Some possible subwoofer alternatives... Yorkville NX200S, JBL EON 518S and PRX 618S

Yes! I like the look and weight of the Markbass Mini. I'll definitely check that out. Thanks!

I know you asked about the QSC K10's but I thought I'd throw this in:

I have a pair of QSC K12's - I do play my full 88 Yam. S90ES thru them... the low end SPANKS!! I actually have to cut it back a little.

I know you asked about the QSC K10's but I thought I'd throw this in: I have a pair of QSC K12's - I do play my full 88 Yam. S90ES thru them... the low end SPANKS!! I actually have to cut it back a little.

Very cool man.

I use a single k10 as monitor at home and occasionally as a mono keyboard amp for shows. The sound is good even though it's mono, and there's plenty of low end even without using the DEEP mode.

76 pounds IS a bunch to carry, hadn't really thought of the weight of the K Sub - I might just as well use my big Trace bass amp and either cabinet if I want more low bass (already paid for - taking up floor space already). I still think for piano that the K10 is quite adequate - I pump Hammond bass from an Electro 3 through mine frequently. If I was 30 years younger, I'd have bought the K12's - still think 12" is the sweet spot for keyboard amp.

I too have a K12 and S-90 XS and it is the best sound reinforcement I have ever had.