One for the Speaker Techie's!!

[Totally Plucked]

Considering adding a small Active sub to the Active 15's I'm using at the moment. It has to be a 12 due to weight and my back etc.

Popped over to my local dealer today (Zelma sound & light) and heard the Kam Kab 12 (quite impressed) so it's a toss up between this and the Alto TS12A.

The spec states the Kam is 600watt RMS ...The Alto 300watt RMS. Now due to speaker sensitivity SPL etc a 300 watt speaker can sound louder than a 600 watt speaker etc ...Blah Blah Blah.

I have listed the spec for both speakers, which do you think would be the better? your opinions please

Kam KAB 12 - 12 Inch Active Subwoofer (SINGLE)

Features:

· 600w RMS active bass speaker

· Power handling: 600w continuous RMS, 1200w program power, 2400w peak power

· 12 inch driver

· Steel woofer chassis

Specifications

· Sensitivity: 94dB

· Frequency response: 50Hz-120Hz

· Audio input connection: XLR

· Audio thru: XLR

· IEC mains

· Fuse rating: 20mm / 6.3A

· Rated voltage: AC 115V-230V switched

· Power consumption: 65w

· Leads supplied: UK/Euro IEC

· 35mm pole mount

· Dimensions (WxHxD): 400 x 450 x 415mm

· Weight: 16Kg

· Product code: 4403

Alto Truesonic TS SUB 12 Specification:

· Power System: 600W Peak / 300W RMS

· Frequency Response: (-10dB) 47 Hz-125 Hz

· Maximum SPL @ 1m (half-space): 120 dB continuous / 123 dB peak

· Transducer Low: 12" Woofer, 2.5" voice coil, with double ventilation

· Active Crossover: HPF 80 Hz under analog processor

· Input Connector: L-R Input (Combo/XLR-F) / L-R Link (2-XLR-M) / L-R Output (2-XLR-M) Balanced (15 kΩ)

· Input Level: L-R Input Line 0dBu

· External Control: Volume Control/Phase Switch/HPF-80Hz By-Pass / Power on with Green LED/Clip Limiter with Red LED / Ground Lift

· Enclosure Construction: 15 mm Plywood cabinet, glued and reinforced, resistant black paint; metal grille, rubber foot

· Mounting: One metal standard pole-mount plus one metal handle

· Alto TS SUB 12 Dimensions (H×W×D): 370 × 530 × 480 mm (14.6" × 20.9" × 18.9")

· Alto TS SUB 12 Weight: 18.6kg (41lb)

· Alto TS SUB 12 Dimensions (WxLxH): 14.57in x 20.87in x 18.90in

· Alto TS SUB 12 Weight: 41.01 lb

[Excalibur]

Problem is ( unless I've missed something ) we're not comparing apples with apples. One shows sensitivity, and the other max spl. Perhaps the clever types can extrapolate one from the other, but I certainly can't. That would only have given perceived volume, which in my opinion isn't enough to choose a sub on.

Basically, since I have no experience of either, I can't help, sorry.

[Totally Plucked]

Problem is ( unless I've missed something ) we're not comparing apples with apples. One shows sensitivity, and the other max spl. Perhaps the clever types can extrapolate one from the other, but I certainly can't. That would only have given perceived volume, which in my opinion isn't enough to choose a sub on.

Basically, since I have no experience of either, I can't help, sorry.

Cheers for the reply Pete, same here I'm not knowledgeable to work it out either !

[AndyC]

I don't have any info on the subs you have mentioned but I have 2 Electrovoice ZxA1-SUB's 800 watts rms only 20 kgs
and I find for most places I have been 1 is normally enough.

Andy

[katman]

Sensitivity is normally given for a 1W input. The more power you put in the louder it gets according to the following formula

db gain = 10 * log(power2/power1)

so given that they rate it at 600W (assuming the amp gives that out), it works out at 10 * log(600/1) = 10*log(600) = 10* 2.78 (call it 2.8) = 28db higher at maximum output, add the sensitivity to that 94+28 = 122db theoretical maximum SPL

The Alto claims 120dB with its 300w amp (123 with its 600w peak), a doubling of power only increases the level by 3dB so I would say they are pretty much identical. Of course the REAL way to find out is to give them both a damn good thrashing !!!!

[deltic]

Although you don't say what model active 15's you have, adding a single 12" sub won't add much to the mix and will probably be overpowered/drowned by the tops.

[Excalibur]

Although you don't say what model active 15's you have, adding a single 12" sub won't add much to the mix and will probably be overpowered/drowned by the tops.

The theoretical preferred scenario is for the size of the driver to increase as the frequency decreases, in order to shift more air. As Andy says, with 15" tops, 18" subs would be preferable. Twelves may indeed not add much to the party.

Then we try to trade off low weight, ease of moving and physical size against desired effect. That's a tricky one, and pretty much a " try before you buy " scenario, for if the twelve inch subs add little to your sound, you've wasted your money. Can you borrow any twelve, and/or fifteen inch subs for a trial?

[addoaddo]

I would be sceptical at either of these manufactures giving you a correct power output figure, these are “adjusted” to make them sound better as a lot of people think more watts is louder.

Generally you cannot get a light Sub as a good sub needs to have a large magnet and a strong construction. Given that the Alto says it is made out of ply is a good sign but a 2 ½ inch magnet is very small for a sub.

As others have said given you main rig o would doubt these would add anything to your set up. As a rough rule I would double the power of the full range for the subs, which goes against what I first said but is correct for a similar designed system

[Excalibur]

I can't resist throwing this one in any longer. In my humble experience, as a general rule ( though not in all cases, as I just know we're going to get loads of examples ) passive subs are lighter than actives. Perhaps one passive sub and a lightweight amp might be an option? If it were big enough ( and I haven't done the sums yet ) a Peavey IPR and one 15" 8ohm sub might fit the bill. Just a thought.

[deltic]

I can't resist throwing this one in any longer. In my humble experience, as a general rule ( though not in all cases, as I just know we're going to get loads of examples ) passive subs are lighter than actives. Perhaps one passive sub and a lightweight amp might be an option? If it were big enough ( and I haven't done the sums yet ) a Peavey IPR and one 15" 8ohm sub might fit the bill. Just a thought.

Fancy you coming up with an idea like that............though i fear it may have been done before