subwoofer expert needed....

[dvjorge]

Hi guys,

I am triying to find a way to improve my JBL PB-12 sub or change it. The first option Iam concidering is to change the sub driver, but I removed it to see its quality, and the driver looks very well built. I don't know if changing it for a Peerles, Eminence, Dayton or any other could make a difference. Also, I noticed the JBL doesn't have any absorbing material inside. I don't know if some insulation material could benefit the bass performance. Second option is to buy the new Klipsch 12'' Synergy Series which impressed me a lot. The bass I like is the "floating type" I mean tha bass which gives more deep time, insted of be fast and solid. It is difficult to me explain it since English is my second language. I hope you can understand.
Thanks for any help.
George.

[Mr Peabody]

If you know the Klipsch does the job, buy that, you may keep throwing money into that JBL and never get it to satisfy you. I don't know what the cost of the Klipsch is but if you like low vibration bass like for home theater the upper end Velodyne are awesome. Like around the SPL series. If you have the funds the Martin Logan's can also move some air.

Damping material always helps a speaker, If you haven't yet, try playing around with the JBL's position in the room. You'd be surprised how much difference placement makes in a sub.

[kexodusc]

Agree with Mr P.

You could put a good driver in the JBL, but I would suspect the cabinet is built to certain standard consistent with its original price range, and a higher quality, heavy duty woofer is likely to demand a new amp, and better cabinet (yes, with damping material) or you won't be getting the best out of the new driver.

[dvjorge]

Thanks guys. I had time without write any topic but I know you. I am member of the forum since 2002. Yes, the risk of change the driver could be a wrong step. What happen is I don't have too much space since I live in a condo. The new Klipsch Synergy Series is a good sub but nothing to be crazy for it. The box is bigger than the old model and price isn't cheap. It is around $600. In this price range, there are a lot options. HSU has the VT II Mk 3 in 499 (black finish), and I am also looking the new Paradigm SC series, the 3200 looks awesome, but I don't have any referece about how it sound. Do you think it could be good idea to fill the JBL box with some damping material?
Thanks.

[Vardo]

If you like the sound of the Klipsch sub, then go for it....personally
I would try out the HSU VT2/3 as it is a tremendious value and
a great sounding sub.

Give it a try, 30 day money back garantee....good luck , vardo

[Alex at SVS]

I agree with the above that replacing a driver could do more harm than good since enclosure space needed for a driver is made up of several different variables. As far as putting damping material, there's a lot of cheap options and if you're looking at grabbing a new sub anyway, yes and I think you learn a lot just from the experiment. Who knows, maybe you'll like it so much you won't even need a new one ;^) I don't think there's any real risk of breaking the sub with it though, just be careful not to strip the enclosure box tightening the woofer back in (something I've done myself)

If that doesn't work out for you though, Klipsch is certainly a quality speaker company and from a buying POV is much easier since you can listen before you buy. I'd suggest doing a little research on SVS subs as well though since if floorspace is at a premium an SVS PCi sub might be perfect for your room. They use a cylinder design to minimize floor space while still using a large enclosure volume that good, deep bass needs to sound its best. If your room is under ~1500 ft3, then go with a 25-31 and we'll custom tune it down to 20Hz at no extra charge. This is going to drop SPL a bit, so if you're over 1500ft3 I'd suggest going with a 20-39 instead (same tuning point, but has a larger enclosure space so it won't drop as much low-bass SPL) And we've got a 45-day trial period if that's a concern as well.

Alex
SVS Customer Service

[filecat13]

As much as I love JBLs in general, I'll say what others aren't: the PB-12 is an old dog, and you can't get it to do any new tricks for you. It comes from a time when JBL's entry level subs were not very good. if you google it, you'll see many people who have had problems with them, so I wouldn't even try to improve it.

Almost anything from SVS, Hsu, and Velodyne will be better, even 10" models. JBL's more current models would fare better than the PB-12 as well, but if you're spending less than $400, I'd recommend one of the above rather than another JBL.

However, if you truly want to kind of bass you say you do, you're probably going to need to spend more than $400 to get it.

[Mr Peabody]

Alex, I haven't looked at SVS before but I plan to, they sound interesting. Are the cylinders sound as critical to room placement as a box? I'm assuming since they save room the cylinder stands up?

[Sir Terrence the Terrible]

Alex, I haven't looked at SVS before but I plan to, they sound interesting. Are the cylinders sound as critical to room placement as a box? I'm assuming since they save room the cylinder stands up?

Its not whether the cabinet is a box or a cylinder, its the wavelengths they handle. Below 200hz ALL subwoofers are at the mercy of the room. A cylinder is not going to change the way a wavelength propagate into the room, but it does tend to lessen or eleminate enternal cabinet resonances.

[Mr Peabody]

I would think the enclosure would make a difference. It makes a difference in my subs response depending on which way the driver fires. Like, back wall, front wall or side, each direction provides a different response in my room. The only cylinder enclosures I've dealt with were Bazooka tubes and they did have a recommended way it should be installed to optimize performance, of course that's a car. I was thinking if the cylinder stood up there may not be any walls for the wave to hit and therefore may be easier to place. This does raise another question as to how the wave would travel from a cylinder. I need to visit their website to see what I can gather.

[Sir Terrence the Terrible]

I would think the enclosure would make a difference. It makes a difference in my subs response depending on which way the driver fires. Like, back wall, front wall or side, each direction provides a different response in my room. The only cylinder enclosures I've dealt with were Bazooka tubes and they did have a recommended way it should be installed to optimize performance, of course that's a car. I was thinking if the cylinder stood up there may not be any walls for the wave to hit and therefore may be easier to place. This does raise another question as to how the wave would travel from a cylinder. I need to visit their website to see what I can gather.

Mr P,
You have a couple of things confused here. What you are describing is not the orientation of the driver in the box, or the box type. You are talking about the relationship between the distance of the driver itself to an adjacient wall, different animal. This is more a room induced response than a driver positioning response. The closer you put the driver to the wall, the more the wall has an impact on the total output from a frequency response and amplitute perspective.

If you took your sub and placed it in a anechoic chamber, no matter which direction you turned it, it would measure the same at frequencies where the bass is omnidirectional. The wavelength of the signal in relationship to the size of the cabinet is more important, as deep bass waves are so long, they just bend around the cabinet at any frequency, and with any enclosure. The long wavelengths take the cabinet out of the equation, and driver orientation as well. Since the wavelength of a 20hz signal is 54 feet, any wall or surface less than 54 feet away will effect the output at that frequency. This is why driver orientation, and cabinet type do not make a difference in the way bass propagates within a room when frequencies are low.

[Alex at SVS]

Yes, the cylinders stand up. The 25-31 stands about 31 inches tall (that's where the 2nd number comes from in the models) and they're 16 inches in diameter. Sonically, they're almost identical to box subs. The real determining factor on how low end bass is handled is enclosure space much more than the box shape. This is one of the main reasons small subs can almost never handle below 30Hz bass well, if they can even touch it. Since bass is omnidirectional, placement should be considered the same as how you're position a box sub.

Hope that helps.

Alex
SVS Customer Service