Motion Sound KP-100S 208 Combo

I owned this amp for a 14 months and just sold it. Great features. Three band eq. Spatial expander.

The amp is too heavy for the volume it delivers. It should have been made of lighter materials in my opinion.

I felt a need to replace the woofers with an OEM woofer made by Eminence. Without the woofer replacement, I felt the bass response was lacking. The new woofers added 5 lbs. to the weight.

The biggest issue I had with this amp, is it just doesn't get loud enough. For 38 lbs., the amp does not put out 100 watts of volume.

Playing keyboard and singing, my voice would regularly distort at relatively quiet volume.

Built like a tank.

They're very nice at Motion Sound. They shipped out a replacement rubber handle (I misused it) very quickly. They were very eager to hear why I was selling it, and they wanted to know what I was replacing it with - two Yamaha MSR100 powered speakers.

I have a friendly acquaintance who gives me great prices. Don't expect to pay less than $500 for this.

This is the little brother to the popular KP-200s stereo keyboard amp, which I also own. So I'll be comparing the two quite a bit. Very easy amp to use.

Like the bigger unit, the KP-100s has basically the same features: (2) pairs of stereo 1/4" inputs (the KP-100 is a one-stereo-channel amp, unlike the KP-200s which has two seperate channels and two sets of EQ and volume controls), with knob controls for bass, midrange, treble, and stereo expansion. The EQ is active so above 5 is boost and below 5 is cut. There is also a master volume control and both a 1/4" hi-z and XLR lo-z mic input. On the back are a pair of XLR direct outputs and a 1/4" subwoofer output. Not featured on the KP-100s from it's bigger brother is the handy "click input" that allows you to use the KP-200s as a vocal monitor without passing the monitor signal back out through the direct outs. The KP-100s features a pair of 8" woofers and horn tweeters. Simple grill cloth cover that looks easy to damage so I bought an nice padded amp cover from Larry LeCover (www.lecover.com).

This is a very compact and lightweight amp - about 32 lbs. It's the only small dedicated stereo keyboard amp I'm aware of (somebody kick the other amp makers and wake them up please...).

Like it's bigger brother, the makers of the KP-100s expect you to set this amp behind you about 2' off the floor and tilt it towards the back of your head using an amp stand. It'd be nice if there was some tilt-back legs or something on the amp but there isn't. I find that the amp sounds best when I can put it directly behind my head about 2-3' back by sitting it on a shelf or on a cabinet or something. But nothing pointing at the back of your head sounds as good as when it's pointing towards your face, so it seems that no matter where you set it, the audience will get a better overall sound from the KP-series amps than you do.

On the sound: this ain't no KP-200s! What I mean by that is the bigger KP-200s benefits a great deal from the 10" woofers and has a remarkably full sound. The little KP-100s' bass response is much less than I expected and the rolloff is obvious. I play as a single act and my keyboard plays bass/drums etc. in addition to the key sounds - with the KP-200s I have no problem hearing every bass note faithfully but with the KP-100s some bass notes just vanish altogether. I know of at least two KP-100s owners who have replace the woofers with speakers that have heavier magnets and report a improvement in bass response (at the cost of adding to the weight). I may go that route myself eventually. But by the time you add the cost and weight of beefier woofers, you might as well have gotten the KP-200s IMHO. Motion Sound should've used better quality woofers, hence the "8" rating for sound.

But let me say that the overall sound of the KP-100s is clear and balanced otherwise. I see this being the amp of choice for jazz gigs. I bought it to use in very small intimate rooms that I play, and it's perfect for that. In fact, other people who play the same rooms with their regular full-size keyboard amps and powered speakers tend to overwhelm the room with bass even at low volumes. The people who like my KP-100s amp the most are the club managers who think it makes more sense to use a little amp than to bring in in a large beast of an amp only to set the volume at "1". I've already won a couple of gigs over my competitors because of this, so the amp paid for itself immediately.

I would not use this amp in a band situation unless it was a low-volume acoustic jazz gig. I'll bet the KP-100s would make a fine acoustic guitar amp also.

And finally, I really do like the stereo expansion feature that is the same on both the KP-100s and the KP-200s. If you use just a little then the sound seems to come from a spread of speakers rather than one box... too much and the reverb tends to overwash the rest of the sound. If you haven't heard it then you'll just have to trust me: the KP-series amps have a lot better stereo image than you might think, and the stereo enhancement effect carries throughout a room.

Seems solid enough and Motion Sound has an excellent reputation. The outer covering of the amp is the same tough stuff used in truck bedliners. Still, the front speaker grill seems exposed so I recommend a cover. Otherwise this is a sturdy little guy and I'm sure it's reliable.

Never had need for customer support with Motion Sound so far but I've heard nothing but postive comments.

If I could only own one keyboard amp or if I played in a band then I would own the larger KP-200s because it sounds better and has more power than the KP-100s... but it's also a lot more cumbersome. I'm lucky to be able to own both the KP-100s and the KP-200s and can use each where it's appropriate.

I bought the KP-100s for a specific use: small intimate solo gigs, and for that it's fine. Again, I think it's ideal for jazz gigs and the like. The bass rolloff of the KP-100s is noticeable even when you are only playing piano through it so you really should try this amp in a quiet environment and listen to it carefully before buying it. The KP-100s has made a good impression where I've used it, both with the management and the audience. If you don't need a lot of power and especially bass then this may be the perfect keyboard amp for you... in fact, if you're looking for a small stereo keyboard amp then this may be the ONLY amp for you!

Ease of use? It couldn't be easier. Owner's manual is three pages long, and only printed on one side per page! That's how simple it is to use.

The KP-100s is a stereo amp with 50 watts per side. It has (2) 8" Eminence Alpha speakers and (2) horns. The frequency response is listed as 70-17Khz with a crossover at 3khz. It is 15"H x 19"W x 13"D and weighs 38 lbs. There is two sets of 1/4" stereo inputs (for two stereo keyboards) and one balanced and one unbalanced mic input (they go into the same channel as the keyboards). There is a mic volume control but really this is a one channel amp: master volume and EQ are global. Active EQ: Bass, Middle and Treble boost/cut controls. There are also stereo XLR line outputs and a 1/4" unbalanced subwoofer output (does not disable bass output of the amp when used).

The "stereo expander" is actually a stereo phase control and is the same kind used in those so-called "vocal eliminators". It works by reversing the phase of the stereo signal (does not work on mono inputs). Also note that the recommended way to use this amp is sitting on a tilted amp stand about 2' off the floor directly behind you (pointing at the back of your head).

Wish list: parametric EQ would be a big help. Some KP-100s owners have replaced the woofers with better speakers that can reach lower frequencies (this increases the amp's weight though).

Ok, you have to qualify the "how does it sound?" question by noting that this is a very small amp and is not meant to compete with guitar amps or large PA's. I own the larger KP-200s also and if you are considering an amp for use in a band or club or any room with more than 50 people, go with the KP-200s which has twice the power and all the bass you'll ever want for keyboards.

Having said that, the KP-100s sounds great. It's very clear and not muddy in the least. Good clean power and sound for such a little amp. Just being stereo makes this amp sound better than any other small keyboard amp on the makret IMHO. The stereo expander circuit is a big plus because it amkes the sound seem like it's coming from seperate speakers. Too much expansion sounds like too much reverb so you use this judiciously. The sound overall is well balanced - very important for piano especially.

However the bass rolloff is very noticeable if you play keyboards with accompaniment through it... it seems to me like some of the bass guitar notes just vanish at times. I think better woofers would solve this but at the cost of adding weight to the amp. OTOH if you are playing in intimate rooms where too much volume and/or bass are prime considerations, or you don't use accompaniment, then this isn't a problem. This would be an especially great little keyboard amp for jazz.

The question comes up: wouldn't seperate powered speakers sound better? IMHO, yes they would - especially because if you use the KP-100s as recommended then the sound hits the back of your head, not your ears, so the audience hears you better then you do. But powered speakers require more cables, power and effort to use and should have a mixer to act as a preamp and EQ controller; whereas the KP-100s is much quicker and easier to setup... and having the sound hit the back of your head doesn't sound as bad as you might think. I own a pair of powered JBL EON G210's and I'll probably use the KP-100s more often.

I've owned a KP-200s for over a year with zero problems. I know lots of Motion Sound amp owners and I've never heard of anyone who's had a problem with them. Motion Sound seems like a good company and their products are very highly rated. Also, the KeyPro (KP) amps are covered with a polymaric coating like they use for pickup truck beds and it's plenty tough. However the front speaker cover has no protection and is bound to get torn or damaged so I would highly recommend buying a padded cover for your amp from Larry LeCover at http://www.lecover.com/.

Never had the pleasure but I hear the people at Motion Sound are very amiable.

This is the smallest, lightest, handiest, cutest keyboard amp I've ever owned. And despite my misgivings about the 8" woofers, I am glad I bought it. I have to play in small, intimate rooms often and I should have bought the KP-100s long before I did. I was worried about what I'd read about the bass response (concerns are justified if bass response is important to you, unless you also want to use a subwoofer - but if that's the case then you need the bigger KP-200s anyway) but frankly in small rooms I haven't missed the bass like I thought I would. In fact, I think this is the ideal keyboard amp for light jazz, acoustic acts, or any situation where quality low-volume music is desired. I'll bet the KP-100s would make a terrific acoustic guitar amp as well. It has great clarity (that's it's best feature), good power for it's size, and the stereo expander really does make a difference if you use it sparingly. Even my wife can carry this amp comfortably (no I don't make her carry my gear - she wanted to try it), and it slips into my VW trunk with room to spare. Again, buy it a padded cover and protect your investment.

One side note: my KP-100s had just arrived so I took it to a new gig for me that was a very small room, about 50 people capacity. The regular pianist used a hefty Peavey KB-300 keyboard amp. After I played my first set, the club owner came over to see what kind of gear I used, especially the amp because they had often had customer complaints about the music volume. I was only supposed to play one night but I wound up taking over some of the regular pianist's nights... so in that sense, the KP-100s paid for itself the first time I used it.

Stereo keyboards really should have stereo amps and few companies other than Motion Sound have addressed this need. The KeyPro amps are the answer. I doubt there is a better small keyboard amp on the market than the KP-100s. If you need a small keyboard amp, this is the one.

This is a stereo 50 watt keyboard combo. Quite compact and very easy to transport. 2 stereo channels + 1 mic channel. Made 2003.

The front panel is very straight forward. 4 x 1/4 jack sockets (Channel 1 Left, Channel 1 Right, Channel 2 Left, Channel 2 Right), Pots for Gain, Enhance (stereo balance) Bass, Mid, Treble. Then there's the Mic input, with 1/4 jack and xlr coskets and a Mic Gain pot.

Back panel has just power socket, DI's (xlr) left and right, 1/4 jack for sub bass output (below 100hz), to connect to powered sub base unit.

The pre-amp works in stereo so true effect of the steroe patches come through. Can run in Mono mode.

Although there are 2 channels, there is only 1 gain pot, with no master gain. In my opinion, the lack of master gain/vol is quite limiting. Also there is no effect send or return, again quite limiting.

I use a Roland VK8 and D50 and play mainly acid jazz, so the organ is the main instrument. The sounds this thing produces are very smooth and musical. Patches really come to life when in true stereo, especially the VK8, really give the leslie sim a lifelike doppler sweep.

My main criticism is that it's not loud enough! Its a 50+50 watt combo, but its a very quite one! I would expect to get more volume from a twin 50 watt amp.

I'm not expecting earth shattering power form a small combo, but I would expect it to compete in the volume stakes with a similar small sized guitar and bass combos. Unfortunately it doesn't and often needs Di ing to help the sound along.

Also when DI ing, the lack of a master gain after the DI out is very annoyin as you cannot change your onstage moinitor volume with out affecting the front or house sound.

Fine so far, seems well built.

Had no need to contacts them.

Overall its sounds great but is too quiet for lots of gigs. Example, many of my gigs are small UK pubs (maybe 75-100 people) and it sometimes struggles if they're full.

Also the lack of Master Gain limits usefullness when used on bigger stages as a monitor.

I'd recommend it as a practice amp or for very small gigs. If you want something bigger venues this isn't the box for you.