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I'm trying to get more punch or kick out of a 2245. The system that I had before my 4345 clones had dual 15" 2226 drivers. It had some serious kick.
My amp is a RAMSA WP9440 with 350 watts, I'm thinking I should try a bigger amp first? Maybe 6-700 watts?
Would a 2240 or 2242 be a direct replacement for the 2245 without changing the tuning? I'm not sure if I really need much below 50Hz, I just listen to 70s music, no home theatre.
I don’t think of the 2245 as a kicker... it is more about musicality and finesse. Where are you crossed over and to what?
If you crossed over at 250Hz to a 2202, I imagine you would have all the “kick” you could want.
Widget
I am crossed over to a 2123 at about 250 Hz right now. I've tried anywhere from 150 Hz to 300 Hz, I have an Xilica XP4080 active crossover. The red lights flash on my amp right now when I play it loud, that's why I'm thinking I might try a larger amp.
Basically it's winter here and I am bored and have too much time on my hands to think. I am thinking of buying a larger Crest amp, like a CA12, or a Crown Reverence 1 that is 760 watts.
You have me scratching my head. If you don't have it now more power is not going to do it. You should have the "kick" at any power level. Even if you X4 your power it's all headroom and at 100db,which should be a cake walk for 2245's, it should be there.Quote:
I am crossed over to a 2123 at about 250 Hz right now. I've tried anywhere from 150 Hz to 300 Hz, I have an Xilica XP4080 active crossover. The red lights flash on my amp right now when I play it loud, that's why I'm thinking I might try a larger amp.
Try placement.
Rob:)
Quote:
Originally Posted by robertg
Hi Robert,
What are your 4345 clones currently tuned to?
I would first try moving the box tuning upwards ( after verifying what the current tuning is ).
FYI, boxes tuned too low ( sometimes done by accident ) can stress the woofer making it lose punch by wasting output/cone-movement on those frequencies that are barely heard.
Have you verified that your 2245H's have actual JBL cone kits installed ?
:)
BTW; I do have a few retired Crest CA12's here collecting dust ( they require a dedicated 20-30 amp circuit to work their magic ).
If it’s a clone you might follow Earl’s lead.
I have listened to 4343’s quite a bit with 2235 fifteen inch woofers.
The perception is they hit hard but in reality they don’t have the linearity of the 2245 bottom end.
The 4345 has a very immersive presentation which people tend to like.
It comes down to taste in the end. Think Stargate. It takes to somewhere else.
If you can get them six inches off the floor everything works better.
Getting the blend right between the 2245 and the 2123 is best done with a modified second order crossover. The low and high pass are not symmetrical. The passive bandpass filter used from the 4344mk11 behaves very differently in Biamp mode. Greg said you have to measure the voltage drives on the actual driver terminals. He knows. I went this route because it works beautifully with my 2420 drivers and dusted titanium diaphragms. The blend is inperceivable right across the spectrum.
Some claim good results with the 3155 network using 2123 with 2446 drivers on 2311 horns. Whatever floats your boat.
I use a Yamaha Power amp 800+800. 350 watts should do it.
It usually takes a little while to set these systems up to give their best.
Something you may want to try, just for "shits and grins" is to let this run as a 3.5 way. IOW, don't the run high pass cap on the 2123 and let it roll of naturally at it's bottom end. You can just "jump" around the cap (but may need to disconnect the choke if present) for a trial. You won't hurt the 2123 in a home setting and may prefer the results.
This is what I ended up doing with the 2251J/2241H combination, and is the best they have sounded. Of course the 2251J has a very nice natural roll off at its bottom end that blends nicely with the 2241 (with 8 mH/95 mfd with a 100 mfd/1.2 ohm "Zobal").
Why would one want to ruin this beautiful rolloff by subjecting it to a cap?
https://lh3.googleusercontent.com/pr...937gpBFQ0KYGMw
I'd start troubleshooting at a pretty basic level. It looks like you're quad-amping? Confirm all your woofers are moving in the right direction with a battery charge applied to the binding posts. I've seen several systems with a simple connection reversed internally. Check your amps to speaker connections also. I've seen an instance where 1 end of a Speakon connector was accidentally wired backwards. You could put a 1kw amp on those woofers and get no bass if 1 is out of phase.
After confirming the above is all good and still no bass, you could try reversing polarity on just the 2245s with your crossover or at the binding posts and see if that helps.
Do you have measurement tools?
Depending on your definition of "punch" it may have nothing to do with the 2245s.
"Kick", "snap", "punch" however you define them can occur at frequencies pretty much all over the map! :dont-know:
My first step was to reverse the wires to the woofers and take a measurement. My ears couldn't hear a major difference but using my REW program I came up with this. Now they are out of phase. Green is right, red is left, blue is both.
I will have to check my box tuning next. I followed the plans here closely, so I doubt if my tuning is wrong. I did change the opening to my ports by rounding them slightly. here is a picture of the front of the woofer. I was told they were OEM recones.
Robert,
A couple of things;
(1) The blue trace; I would expect that both woofers playing together would add level/volume ( not subtract level, as is seen in your pic ).
- I think one of those 2245's is operating with flipped polarity to the other ( it could be your system electronics has a phase reversed cable ) .
(2) Unless the woofer cones are coated with aquaplas ( on the backside ) then the cone kits are aftermarket.
:)
That's with one of the woofer cables reversed. I was expecting a graph like that.Quote:
Originally Posted by Earl K
I'll have to pull one of the woofers and take a picture of the back side.
Easy just do an impedance sweep and the lowest value between the 2 peaks is your box tuning. As long as your are in a Hz or two all should be fine.Quote:
I will have to check my box tuning next.
Rob:)
Quote:
Originally Posted by robertg
Maybe just one is out of phase? Got a compass???
I have a 2241 with a reversed polarity magnet and no matter which way I wired them (both being the same), they were always out of phase with no bass until I purposely wired one out of phase. ...So caca occurs..., and from what I understand, it is about 1 in 50.