Active Subs

[DaveySimps]

We are looking into purchasing some active subs for our 636 seat proscenium space. It is a relatively intimate feel due to continental seating and no balcony, so we do not need ridiculous amount of subs, but we have officially decided that the best way for to go (for many reasons) is with a couple of active subs. This is more to enhance effects and music playback, as out LCR system does a fine job with overall sound distrobution. For those of you who have used active subs in this capacity, which ones do you like, which ones do you recommend to stay away from. We have open ins and outs on our DSP, so integrating them into our system in not a problem.

~Dave

[kovacika]

Yorkville UCS1P rocks, especially when paired. They couple very well.

[Eboy87]

Questions:

1) What tops are you using
2) How big is the space
3) What's your budget?

[avare]

Adding to Ian's questions:

4) What SPL are you wanting to achieve?
5) Are you planning a mono sub or multichannel?
6) what in your mind is a "ridiculous amount of subs" and why?

Andre

[DaveySimps]

1) What tops are you using? Renkus Heinz TRX Series (we are not interested in purchasing the Renkus Heinz Subs)

2) How big is the space? The house is 636 seats (17 rows total) in continental arrangements with only a single aisle in the middle of the house. I am working on getting the actual dimensions, but cannot seem to find the drawings as of yet.

3) What's your budget? we are trying to keep the speakers under $4,00o for a pair.

4) What SPL are you wanting to achieve? an absolust max of 105db, even though that would be excessive in most cases, having the option for an effect if needed might be nice conceptually speaking. As I mentioned in my original post, they are mostly to beef up the low end on tracks and for effects, we are happy with our overall system as is.

5) Are you planning a mono sub or multichannel? My inital thoughts are one box per side (depending on the box of course)

6) what in your mind is a "ridiculous amount of subs" and why? two dual 18 sub boxes per side would be ridiculous as it would be WAY over kill in power, plus it would take up to much real estate.

Thanks!

~Dave

[Eboy87]

It's near the top end of your budget, but have you looked at the VRX918SP from JBL? They're a self-powered single 18" box. They also have the PRX version of the same box, but I've only heard the VRX. If you know where to look, and get lucky, you might find a pair of used Meyer 650's or 600's that'll fit in that budget. Now those are nice boxes.

If you're looking to go with a single box per side, I'd recommend staying away from the horn-loaded subs out there. I've never heard them sound good as a single box, YMMV.

The Yorkville offerings are good too, but I personally haven't heard them. THere's always the 18" Mackie, but I've heard (in both senses of the word) less than stellar
things about them; they just don't sound "right" to me. They also used to have a nasty habit of farting, which is the best way I can describe that noise. Whatever you plan to get, definitely demo a pair.

[museav]

How is your system really run? You mentioned having LCR but then talk about one box per side. In a true L/C/R system you would have no sound to left or right with anything panned center, so do you really have L/C/R or is it a mono + stereo system or even an exploded mono array? Are you maybe thinking aux fed subs?

How do you plan to crossover and process the subs? Does your existing system processing accommodate this or would any processing necessary have to be part of the $4,000 budget?

How are the subs going to be mounted and do they need to be flown? Do you have any constraints on size, weight, power requirements, etc?

What type of low frequency response are you looking for?

The 105dB output level is pretty meaningless without knowing the size of the space, so that piece of information is needed for the SPL number to have much relevance.

[DaveySimps]

Yes, I really like the JBL VRX's. I have heard them several times, and they are definately in the running. For this application, I agree with you, we are stearing clear of the Mackie stuff.

Our system is a true LCR system, not l/r + mono. Right now I am thinking they would be run off of an aux. As my original post indicates, our existing DSP has enough available processing, ins, and outs to take care of the job, so the $4k is literally just for boxes, even cableing can come out of another line item if it had to. The subs are probably going to be ground stacked, no flying (again, depending on teh sub). We have 2 20A dedicated circuits available, so power is not an issue. We have a 6'x6' area clear on each side where we can place the boxes with out obstructing anything, so this does give us a decent amount of real estate to deal with. I am still workig on getting the actual drawings, but an educated estimate of the room is 85' at its widest point by 105' deep by 45' in height. The absolute dimension of the proscenium (for comparison purposes) is 52' wide by 28' tall.

Thanks for your thoughts.

~Dave

[mnfreelancer]

I haven't personally heard the Mackie SWA-1801 so I can't attest to it's tendency to "fart" but I have ALWAYS been impressed by the Mackie SRS-1500 and it's successor the SWA-1501. For a 15 inch super-compact cabinet it puts out an impressive amount of well-balanced low end. I have always thought the JBL 18 cab sounds "dry", kind of subjective but that's been my impression.

[museav]

Sorry, I missed the comment on the DSP I/O but there are some processors that may have sufficient physical inputs and outputs yet may not be able to provide the appropriate routing and/or processing so you might want to make sure what you have can be programmed to provide the routing and processing necessary. It does sound like you have the power and physical space issues addressed.

Not knowing the space, my concern with ground stacking is that with a 105' depth you could conceivably have a 20dB or greater difference in level between the front seats and the rear seats. Add to that the 'power alley' from split subs getting the same signal and you might have the front middle seats 25-30dB higher in level than some of the off-axis seats at the rear of the house.

Since it was already mentioned, the VRX918SP can be flown using the VRX-AF array frame, but it would apparently be pushed to provide 105dB to all seats in your room. If you went with the VRX918SP you might be better off to fly two together next to the center array, that would minimize the 'power alley' effects, help even out their coverage of the seating and get some coupling, and thus additional output, from the two subs being together. The Yorkville LS800P seems to not have as low a LF response as the VRX918SPand is not flyable. The Mackie SWA1801 also cannot be flown. It is actually difficult to compare the output of these devices since the specs are not real clear on whether the numbers represent whole space or half space and the Mackie SWA1801 specs actually state a "Maximum SPL @ 1m" of 129dB and then a "Peak Output @ 1m" of 135dB, the higher number may be intended to represent half space loading but it is not at all clear.

Slightly off subject, with your existing R-H TRX mains you will likely be greatly on your own for the system settings and tuning, don't forget to budget for any assistance or equipment you need for that.