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I'd like to purchase a pair of passive speakers for an older amp that has only two channels (no subwoofer or surround channels) to use it as a monitor. I want to get a 3-way speaker set in order to obtain the widest possible sound range (bass+midrange+highs). This is what I found for 400$ a piece:


Grund Audio ST-36HD - 15" Three Way High Definition Loudspeaker


What would you recomend? (Online stores, best speaker companies, etc)

JBL K2 S9800 90KG per speaker
$25,000 per pair



JBL site

Will I loose a lot of bass range if I get a speaker with dual 8" compared to a single 15" speaker?

a couple of things....

3 ways are nice to listen to, but not a good choice for mixing. crossovers always create phase anomolies and a 3way's crossover will be in the vocal range, so mix on the 2ways and listen to glorious playback on the 3ways....

the formula for determining the area of a circle is pi times the radius squared, so a quick calculation shows that a 15" speaker has an area of 7.5 x 7.5 x 3.14=about 176 square inches. an 8" speaker has an area of 4 x 4 x 3.14=roughly 50 square inches. there are two of them moving in tandem, so the total speaker area of the 8" is about 100 square inches. the dual 8" will move slightly less air, but depending on the box and driver design, may give a similar bass response to the 15" speaker. 2 10" speakers certainly would.....

the advantage of the dual 8" driver is extended bass response while still using a driver that has good full range response allowing the tweeter in a 2way system to be crossed over at a point that is well out of the vocal range....

another option to extend the bass range would be a well balanced sub. if you are mixing in a small room, you'll want to have plenty of bass absorption in the room(bass traps, closets full of clothes, something...).

garyb wrote:a couple of things....

3 ways are nice to listen to, but not a good choice for mixing. crossovers always create phase anomolies and a 3way's crossover will be in the vocal range, so mix on the 2ways and listen to glorious playback on the 3ways....

Phase anomalies? Why, how? Then all crosowers will create phase anomalies including the 2-way speakers (they have to filter the highs too!).
I don't have a budget for both types.

garyb wrote: the advantage of the dual 8" driver is extended bass response while still using a driver that has good full range response allowing the tweeter in a 2way system to be crossed over at a point that is well out of the vocal range....

That's a good point. That's exactly what I noticed in the specs for some 8 " speakers, they had the high frequency crossover set as high as 12KHz.

garyb wrote: another option to extend the bass range would be a well balanced sub. if you are mixing in a small room, you'll want to have plenty of bass absorption in the room(bass traps, closets full of clothes, something...).

That's not an option because my amp has only 2 output channels.
Thanks for those good points. I might consider a dual 8" configuration now as opposed to a single 15". Something like this:
http://www.bhphotovideo.com/c/product/4 ... eries.html

sure, the phase problems inherent in a crossover happen in a 2way system, it's true, but a 2way reference monitor's woofer is full range. the tweeter is crossed over very high, maybe 5k, where phase problems are less likely to affect your mix. a 3 way will have crossover points at maybe 750hz and 3k, or 1k and 5k, which are very important bands...

adding a powered sub doesn't require another output. most powered subs go in between your amp and the speakers, or between your mixer's outputs and the amp.

a dual 8 box like that might be a very nice choice for extended bass in a nearfield. the jbl you posted is really a playback speaker(for home stereo). i wouldn't replace a good nearfield with that personally, but i'd bet that box has plenty of bottom. you might consider adding a speaker switch of some kind. the problem is that that box is meant to flatter you music, not what you want in a reference monitor(if that's what you want). how about something like this? it's a little more money, but a lot nicer, if you are using it for mixing. for your stereo, the JBL is probably more than sweet.

i used to use a pair of JBL 4406 and then had a similar speaker to the one you posted for presenting final mixes to the client. currently, i have a pair of Blue Sky Studio Ones, which as a dedicated 3 way system are a pair of nearfields with a dedicated sub. the Blue Skys are clean, clear and accurate, have extended bass and are pleny loud for the big presentation(which ain't that big in my home studio). http://www.abluesky.com/asp/default.asp

i'm not trying to dissuade you from making the purchase you are contemplating, i'm just suggesting that the 2way nearfield is still a vital mix tool.

actually, since we're talking about it and you brought it up, the auretone and other single speaker full range reference monitor are still valued by many engineers because there is no crossover..... http://www.prodistroaudio.com/page15.html ...but then again, westlakes were 3way and they were extremely popular in the biggest studios, especially for tracking, although most of those studios had a pair of auratones for mixing or at least checking the mix....

i guess you noticed the Grund is a PA/keyboard/playback speaker. if you plan on using it for a live keyboard monitor it would be ideal, but it would suck as a reference monitor.

I know the speakers above are for PA, I didn't care as long they had 3-way speakers with a 15" bass speaker.
However, I didn't realize that the phase problem is so common. I understand now why most studio monitors are amplified: phase shifts can be prevented using active filtering with seperate amps for lows and highs. Your BlueSky speakers are like that. Interesting! I'm glad you told me this, now I am thinking differently.
What's the phase shift sound like? There are Phase options in Scope mixers, but I can't hear much difference when I enable them.

well, the phase shift is more like phase cancellation. at the crossover points, you may have missing data, so it will sound like.....nothing where you should hear something. listen on another speaker and, surprise! as to it being common, well there's a cost for every gain. the crossover allows a speaker's range to be extended and components that are suited to each frequency band range to be used, but any filter will be less than perfect in it's operation, so a compromise is made in the steepness of the filter and protection and balance for the drivers. a steep filter protects the drivers better and allows better control of each component, but a steep filter has more phase and harmonic issues. most nearfield monitors use a full range woofer with a gradual dropoff between 3-5k and then a tweeter with a gently sloped crossover that matches the woofer's rolloff. if there are freqs that are coming out of both woofer and tweeter, then each driver must be perfectly in phase to avoid cancellation. since higher frequencies are less susceptable to partial cancellation, the higher the crossover point, the less critical phase alignment becomes.

no problem with using a PA speaker, but i wouldn't try to mix on it....