active speaker system, ideally child friendly

i am trying to put together an audio system which sounds nice, but is also durable enough so that our 3 1/2 year old can push buttons on it. if he does break something, it can be replaced fairly inexpensively.

we will play CDs (classical, rock, folk, and children's music) and mp3s through our cowon d2 and possibly an ipod at a later date.

my thoughts so far are to move the costs away from the electronics, which can be a good idea anyway for budget systems from what i read, but is especially important with our child consideration. therefore, we could buy some active speakers, possibly a sub, and an NHT PVC Pro and hook them to an inexpensive CD player which plays many formats.

so i would really appreciate your suggestions in terms of the components for this system -- speakers, sub, cd player, cheap receiver instead of NHT PVC Pro. i am happy to buy used where i could get better value. one consideration i forgot to mention earlier, and a reason i am a little concerned about the active speakers, is that the room is fairly large (18' x 18' with a 20' ceiling), but we will not be here for more than a few years so i don't want to design everything around this constraint, just make the system work in this environment.

if i should bail on this idea and just buy a mini cd system, please steer me in that direction also.

some ideas:

1) NHT M-00, S-20 and PVC Pro with a good, cheap CD/DVD player.

2) KRK VXT6 with NHT PVC Pro + cd player. used sub or NHT M-00?

3) used Quad 12L with NHT PVC Pro + cd player. used sub or NHT M-00?

because of the nature of this sytem, i don't want to get really crazy budget wise, but i'm not so constrained that i have to keep it as inexpensive as listed above either so if you see a good fit that costs a little more, please let me know. if you think a passive speaker setup would suit our needs better, please let me know.

thanks very much.

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Thanks very much, Bob. A couple of follow up questions.

Would the KRK monitors work well in a large room (18' x 18' with 20' ceiling)?

Would you feel comfortable ordering VXT6 factory b-stock?

The VXT6 with the SVS sub and PVC Pro seems like a good value at roughly 600 + 700 + 80. The NHT M-00 with S-20 and PVC Pro is 750 total which sounds incredibly cheap. From your perspective, is the KRK/SVS/NHT system worth double the NHT only system?

Thanks again for your advice.
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From your perspective, is the KRK/SVS/NHT system worth double the NHT only system?

Yes. You could also get some omnimounts for the speakers and connect them to the wall and keep them out of the way. FWIW: A pair of VXT8 might be another way to go - probably enough bass in those without the sub.
I have been lucky enough to have both my (now) 5 and 7 year old boys almost completely ignore my systems. I handled their curiosities by allowing them to investigate while being supervised. Additionally, I had explained to them that I would allow them to touch things ONLY if they would come ask my permission first. They were made very aware of the consequences. Not one scratch was made by those little monkeys. It depends on how you handle things (sometimes). Cheers.
Thanks you all. Very helpful.

Pricing wise:
KRK VXT8 is 1060/pr
KRK VXT6 is 600/pr

There are used active Quad 12Ls (between 500-750 per pair on audiogon) and perhaps some other used active monitors for sale which might offer better price/performance. What are your thoughts? Any others I should consider?

Bob, here is a link to the 750 pricing for the NHT system is here if you're interested:
(Actually the system above includes the M-00, S-20, and PVC-PC and not the PVC Pro which I'm guessing you could substitute.) After the comments above, I'm leaning toward KRK or JBL or some other used active monitors.

Additionally, I don't have experience with biamped systems, but I am starting this system from scratch so I am not working around incompatible equipment. Can you point me to a link or information which describes what I need to think about for this setup as I expand this system? Design constraints.

Thanks again.
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If you teach him not to touch, you'll have the added benefit of not having non-functioning controls due to sticky finger's.
thanks. i'm currently leaning toward the KRK VXT6 (or possibly VXT8) with a sub and NHT PVC Pro, but I would welcome other options to consider. if there are other monitors with better price/performance, including used options, i'd be interested.

my son seems more interested in pushing buttons on a cd player (and possibly other components) than playing with a speaker so i am hoping to keep the durability high and cost low for the electronic pieces. thanks for all the advice on childproofing the system. i feel good about this.

bob, is the jbl lsr4326/lsr4328 a significant step up from the KRK vxt6/vxt8?

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