How much sub do I need?

[jims]

Re: How much sub do I need?

We have an actual pipe organ, so no need to reproduce those low organ notes. We really just need to cover the 40 to 100 Hz range (ish). Probably the Titan 39 would be better in terms of performance for us, but the T45 has a really attractive form factor.

[badman]

Re: How much sub do I need?

The answer, IMO, is always "More" in an ideal world. For a church, I'd be surprised if a pair of T45s fell short, but with synthesized organ low notes if it gets used for that application you never know. Bill (not surprisingly) is advising you well here, and your call to use a highpass is very important, good thinking.

[jims]

Re: How much sub do I need?

Thanks Bill. I appreciate your input.

Luckily, I don't think we have any need for a professional church installer for this. I just don't want to screw up the specification part of it. ;)

[billfitzmaurice]

Re: How much sub do I need?

Two are either enough or they're not. Knowing how much output you need would help. A pair of T45 should have no trouble keeping up with your mains, I assume the congregation isn't into dubstep, but you never know. As is the case with all horns, and for that matter most subs in general, the larger the box the better the low frequency result. You don't see pipe organs using two foot pipes.
Not to downplay your potential investment, but most professional church installers will charge you $300 just to look at the place and tell you what you need. Add another zero to that for what you'd pay for a modest installation.

[jims]

Re: How much sub do I need?

Build two, add more if required.
Buy once, cry once.

The thing is, that building more than two significantly breaks the budget, and we also have the space constraints described above. I know you don't have a crystal ball, but are we pretty likely to be happy with two? Is there more info I could provide that would lead to a better recommendation? Maybe I could borrow a sound meter and measure dBs during our next show. Would that help?

I have to make the case for this, and if the case is that we're going to spend $1,000 and maybe it'll be enough and maybe it won't, then the expense likely won't get approved. If I can say with some certainty that it will be enough, then maybe we'll build them.

I might be able to build a T45 a bit bigger (maybe as big as 20"x24" could be shoe-horned into the space). I just mentioned the 15x24 size because it is mentioned on the product page. Will that make a noticeable difference in output?

[billfitzmaurice]

Re: How much sub do I need?

At this point, I'm trying just to get a sense of whether just two subs will be enough

Build two, add more if required.

If we went with a couple T45s, would we be advised to load them with LAB12's, or would the cheaper D12LFA be enough?

Buy once, cry once.

[jims]

We have a long-term folk concert series at my church, which is evolving from being mostly solo and duo acoustic acts to having some full bands with more electric instruments and drum sets. The space has dimensions of about 100 feet long x 48 feet wide x 20 feet high (so 96,000 ft3 total), and seats roughly 175 between the main floor and a back balcony. Current speaker setup uses 4 Peavey Impulse 100 speakers, two as mains and two as monitors. These are two-way speakers with 10" woofers.

This setup gives us adequate SPL (we don't want or need rock concert volume levels), but it's noticeably bass-deficient and I think we're pushing the mains toward their excursion limits in some cases. (They're perfectly ok for acoustic guitar, vocals, and keyboards, but not so much for micing a kick drum, and electric bass lacks authority).

The way the front stage area is configured and utilized, we don't have space to leave big cabinets out all the time (other than during the shows themselves), nor space to store big cabinets when not in use. There are a couple smallish triangular spaces against each side wall where cabinets could be placed permanently, but they would need to be somewhat size/shape limited. I measured and we could fit a 15"x24" BFM Tuba 45, or I could build a pretty large (if necessary) vented cabinet to fit in the space.

At this point, I'm trying just to get a sense of whether just two subs will be enough, and if so, what approach I should take. Vented cabinets are a little quicker and easier, but I don't think building the Tuba cabinets will be a problem. If vented, what minimum drivers are likely to be enough? If we went with a couple T45s, would we be advised to load them with LAB12's, or would the cheaper D12LFA be enough?

Cost is an object, but I think we would rather err on spending a little more on drivers up front than have to replace them with something better later on. I understand that crossovers and limiters will be needed as well....