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henapen
08-07-2007, 08:52 AM
Hi, I've recently acquired a pair of JBL 4691B Cabarets for my band but (being a bit of a novice!) I'm unsure what would be the best power amp for these. At the moment we are only playing small to medium venues and I don't intend getting any subs for a while (my bass rig is just adequate) but clearly I would like to bear this in mind for the future. I have used my carlsbro stingray bass head (300W) to try them out but I am aware that this might not be the best answer.

Any advice you could give me regarding the suitability of different types of amp and how best to set it all up would be great!

I've really enjoyed looking through your forums and found them to be very informative - if a little above my head most of the time :o: - so please bear with me if I seem a little slow...

thanks

hen

Zilch
08-07-2007, 11:46 AM
Drive them with a pro amp, and a small mixer if you're using them for vocals.

I swapped out the E140s for 2226H.

Invert on the subs, when the time comes, if you're into stacks:

henapen
08-08-2007, 05:24 AM
hi zilch - thanks for the advice - if I'm looking for a general amp to power these what rating would be most suitable? people say the jbls are very efficient so does this mean I can go for a more powerful amp or stick to one closer to the speaker rating. for example if I go for a 1000W power amp is this likely to cause a problem?

thanks

louped garouv
08-08-2007, 05:31 AM
http://www.jblpro.com/pub/obsolete/Cabaret_Series2.pdf

there's a chart on page 5

:)

henapen
08-08-2007, 06:03 AM
http://www.jblpro.com/pub/obsolete/Cabaret_Series2.pdf

there's a chart on page 5

:)

thanks that's useful - it says 200-400W so I assume I can go for higher rated amplifier but how high?

edgewound
08-08-2007, 12:42 PM
Any advice you could give me regarding the suitability of different types of amp and how best to set it all up would be great!

hen

Hey Hen,

What are using them for? Bass guitar? or PA? and what's gonna go through them?

For live sound, anywhere from 400-1600 watts is safe and clean with more headroom at the 1600watt area.

Your 1000 watts would provide enough headroom, but... with higher power....now you need to put safeguards into place to prevent launching the cones across the room...namely a highpass filter tuned to 40hz and above and a compressor limiter would certainly keep a governor on the signal going to the amp.

The 4691B is tuned to 40Hz. That means if you plan on miking the drums and running keyboards, bass and any other instruments through them than can make below 40Hz you don't want to overwhelm the E140 woofer and drive the voice coil out of the gap or "bottom it out"....which you would hear and doesn't sound good at all....with probable destruction of the woofer.

For PA vocals only, you shouldn't have any problems....plug and play. There are lots of new amps on the market that have a high pass(low cut) filter built in that can be switched in and out.

Hope that helps... and I didn't throw too much info at you:)

henapen
08-08-2007, 01:09 PM
Hi Edgewound (great handle btw :applaud:) thanks for the valuable advice!

I'm mainly intending using the 4691Bs for vocals and guitar (we're a 5 piece with 2 vocals 2 guitars +bass and drums). From what you're saying it probably is not a good idea to send the drums and bass through the jbls (which was my gut reaction anyway) and as we're only booked for small to medium venues I think I can get by with my peavey black widow cab for those going through the bass amp.

What would be the situation if the drums went through the jbls but with a low output volume from the mixer? or perhaps this is tempting fate? Anyway I've got my eye on a hill audio 2x350W that looks pretty cool. fingers crossed.

thanks again!

hen

edgewound
08-08-2007, 01:25 PM
Thanks for the :applaud:on my handle:).

If you must....go very low on the drums...esp the kick drum, because that can kill all your headroom in the blink of an eye.

With small rooms you can usually get by without mic'ing the drums...or just use a single mic between the hi hat and snare for presence.

I'm a guitar player...so drummers...no wait....everyone... bitches about the guitar player being too loud...but he doesn't hear the crack of the snare in his ear on every beat;) like the rest of us in front of him....and he has no volume control other than his sticks and hands...if he's good.

henapen
08-08-2007, 02:00 PM
LOL brilliant summary of the problems musicians face with drummers :p I'm a bassist so I rarely notice anything anyway :snore:

thanks for the advice on the drums - I think I know how I'm going to deal with it now. I pity the band having me as sound guy.....:banghead:


Thanks for the :applaud:on my handle:).

If you must....go very low on the drums...esp the kick drum, because that can kill all your headroom in the blink of an eye.

With small rooms you can usually get by without mic'ing the drums...or just use a single mic between the hi hat and snare for presence.

I'm a guitar player...so drummers...no wait....everyone... bitches about the guitar player being too loud...but he doesn't hear the crack of the snare in his ear on every beat;) like the rest of us in front of him....and he has no volume control other than his sticks and hands...if he's good.

edgewound
08-08-2007, 02:43 PM
LOL brilliant summary of the problems musicians face with drummers :p I'm a bassist so I rarely notice anything anyway :snore:

:banghead:

It's fun to talk with other players on the follies of gigs.

The guys I play with are like brothers to me, and two of them are brothers....but we do have our minor quibbles.
Same group of us has been at it almost 20 years now.....and it's still fun and therapeutic.

henapen
08-08-2007, 03:28 PM
Yeah I'm really happy to get back into it - it's been over 10 years since I was last in a serious group and back then we always seemed to be playing in venues with pa's all set up, now I'm doing it for myself I'm seeing how much effort actually goes in to the whole deal.... our lead vocalist is in a never ending debate with the lead guitarist but they love each other really :bs:


It's fun to talk with other players on the follies of gigs.

The guys I play with are like brothers to me, and two of them are brothers....but we do have our minor quibbles.
Same group of us has been at it almost 20 years now.....and it's still fun and therapeutic.

henapen
08-16-2007, 12:56 PM
thanks for the great advice on this thread - I'm feeling a bit more confident but I still have some (fairly basic) issues. For example - I'm considering an amp that produces 600W on two channels into 4 ohms. Now I assume that if I put that into the JBLs at 8 ohms they will produce 300W - if I bridge it then will it do 600W?? and is all this safe for the amp and the speakers!?

Also because I will only have one amp I can't bi-amp so what is the best way of ensuring the speakers produce plenty of low end? is it just a question of boosting the level on the mixer or can they be set up in a particular way?

I apologise if these issues a) are really :blink: and b) if they have been answered in previous links - I have had a look and can't find the answers I need.

Once again I put my trust in you good people to help put me out of my misery!!

thanks

hen