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safdiscos
05-08-2013, 05:06 PM
Hiya, I've been pondering buying a sub for a while now, i run two Alto ts115A active speakers, which I think sound fine, but I've had a couple of comments about the lack of bass, and I've got a couple of 18th birthday parties coming up and I'm sure they will be expecting the music to 'boom' as it's gonna be dance music and all that kinda thing. So my questions really are, do you all run subs at your gigs? also I'm limited really with how much space is left in my car and I'm thinking the Alto 12' sub would be a good compromise?. I saw the Alto sub has been mentioned on here before, has anyone bought or heard one yet?
Thanks
Chris

Excalibur
05-08-2013, 05:37 PM
Interesting that you are suffering an apparent lack of bass from 15" cabs. While I know you're not going to get the response possible with big wooden cabs, I've heard 12" plastic cabs give adequate bass without any processing, John's RCF 312s springing straight to mind.

As to sticking a 12" bass cab under them, well it's not the ideal configuration. A 15" sub and 12" tops would be preferable, but that's just me believing that "ye cannae change the laws of physics". :D I'd be a lot happier with a 15" sub feeding your 15" tops with high only, but if space and cost are an issue, well that constrains you somewhat.

Anything should help, and if you're struggling for bass, you could try running the tops full range to get as much as possible, but again, it's not ideal. I'm sorry I can't give any more helpful advice, but bear in mind two things.
1) If at all possible, listen before you buy.
2) When and if you've bought a sub of whatever size, see what sounds best to you, ie tops running high only from the filtered sub output,( assuming of course that it has one. Not all subs do. ) or everything full range. If it sounds right, it is right. Good luck.

safdiscos
05-08-2013, 05:50 PM
thanks for the advice, I did expect there'd be more bassy as there 15's and i heard them demo'd in the shop, but out at gigs, they do seem to be lacking a little bit, The Alto subs have got a built in crossover so im hoping (as my knowledge is rather limited to be honest) that just running from the mixer into the back of the sub and then upto the tops will sound okay, im gonna give 'get in the mix' a ring tomorrow and see what they say, I just wanted to get some totally neutral views first, i asked at DJkit about the 12' sub and they said they wouldnt bother and to just get the 15' hmmm

chrisj
05-08-2013, 06:44 PM
Hi Chris, I have an Alto TS15 sub which is 600w active and I have found it very good with a lot of control on it. I have never driven it fully but used it as additional sub when using Bose L1 and B1's. Last couple of times I used it with a pair of Behringer B208D 200w actives hanging from my gantry. It gave a lovely bottom end and I took signal to the sub then from link output to a B208D. The other channel straight to the other B208D and I was driving mono.
Getinthemix selling at £299, worth offering £280 and see.
Chris (as well).

safdiscos
06-08-2013, 07:01 PM
ah thanks, I think finding room for the 15' is the thing to do then, if I was to run the top speakers in full range mode, what would the sub be doing?

I appreciate this is most likely a stupid question :P but i don't know

Excalibur
07-08-2013, 08:01 AM
if I was to run the top speakers in full range mode, what would the sub be doing?


Basically you have two choices.
1) All cabs receiving a full range signal. Subs will only reproduce the low frequencies, as as the filter in there cuts out the high frequencies it can'rt reproduce accurately. Tops receive their normal full range signal, and function as normal. This way adds bass to the sound, but doesn't give the tops an easier life by removing the low frequencies which are " muddying" the sound.
2) Sub receiving mixer output, tops receiving filtered output from sub. This way cuts down the range of frequencies you're asking the tops to reproduce, and should allow them to sound cleaner and brighter. It also cuts down on the work done by the amp, as it's the low notes that are power hungry. The subs do exactly the same in each case.

Which way is best? Whichever sounds best to you. Simples.


The basic principle is that the lower the frequencies being reproduced, the larger the driver needed for best results. As the frequencies go higher, smaller faster ones are needed.

Ryu
07-08-2013, 08:29 AM
I run the 2) scenario that Pete mentions above, using SRM450v2's and n SRM1801 Sub and it produces a great balanced sound. If anything, running this combo seems to take the harshness off the tops (along with a little EQing of course)

safdiscos
08-08-2013, 05:22 PM
Excellent advice and help as ever! thanks everyone :)

oligunner
08-08-2013, 10:35 PM
I have the alto 15" actives and they seem to be fine on the bass.

However when needed I do use a bin. But when used its a strange setup as its a passive 18" bin (had given to me) so I run it through a amp via the control room output on my mixer then its a bit of equalising to do but it works for the time being until I get some active bins.

safdiscos
09-08-2013, 04:35 PM
I appreciate this is a difficult question to answer, but the speakers I've got the ts115A are 400 watt each continuous, so numbers wise what are we looking at, the bloke in the shop reckoned 75 - 100 people in a small to medium size venue could be catered for by these.

Excalibur
09-08-2013, 05:31 PM
The simple answer is double your tops combined output, so around 800watts rms. That's the ideal world answer. However, we don't live in an ideal world, so best advice is to get as loud and reliable a cab as you can afford. Then balance the sound with the knobs on the back. They turn down as well as up you know. Match the tops to the sub, then alter the volume with the mixer


Don't get hooked up on figures, as long as you don't buy a really small one and redline it permanently you'll be fine

paulg
09-08-2013, 05:47 PM
it's not the wattage that is important - you need to look at sound pressure levels (spl's) in decibels (db). For the Alto's you are looking at about an average of 124db which is so so. I reckon he's about right with the estimation of 75 - 100 people without you having to drive the nuts off them. Still, they aren't a bad offer at 800 quid or so for two powered tops and a powered sub

During your search for new speakers, you are best to look at the SPL's and not watts because it's very common now for manufacturers to put the same size amp in a whole range of speakers of driver sizes and outputs. (It's cheaper for them to mass produce one amp module rather than several different ones tailored to different speaker cabs).

The only downside is how quoted SPL's are measured - some are actual measurements in the real world, some are calculated mathematically. Others are measured using pink noise. Mackie often say that their SPL's might look lower than other manufacturers but that's because they are measured and quoted honestly. Still. it's fair to assume most manufacturers will quote the most impressive figure they can so it's still a reasonable way of comparing things.

Your ears and your other senses are by far the best judge.