PDA

View Full Version : Replacing Bass unit 813B



David Ketley
07-27-2010, 07:50 AM
The cones are shot on the base units on my 813Bs and the cost of a recone is so high Im looking at just replacing them. Eminence suggest Kappa ProLF-2 or I could get some JBL units 2225H, E140, or K140. Anybody gone this direction if so what did you use. I also use a subwoofer with these speakers to fill in the lower end they are sounding very nice even though the bass units are slowly dergrading.
Dave

scott fitlin
07-27-2010, 09:21 AM
Well, you could replace the drivers with the models you list. BUT be prepared for a DIFFERENT sounding 813B!

The Eminence drivers sound NOTHING like the original drivers used in the 813. And, without reworking the passive crossover for the characteristics of the Eminence drivers, you run every possibility that your 813B doesn't work properly at all.

David Ketley
07-27-2010, 10:47 AM
Thanks Scott thats just what I wanted some honest opinions, I did not realise changing the unit would have such a profound affect on the final result!
Dave

SMKSoundPro
07-27-2010, 12:41 PM
Have the OEM drivers reconed, and the passive re-foamed.

You'll be very pleased!

scott fitlin
07-27-2010, 12:50 PM
Thanks Scott thats just what I wanted some honest opinions, I did not realise changing the unit would have such a profound affect on the final result!
DaveDavid, hi, welcome to the forum,I have a question. I see you are in the U.K. and am wondering exactly HOW MUCH it is to recone your original JBL woofers?

It is expensive to do here, as well, but, it IS your best option!

David Ketley
07-28-2010, 12:19 PM
Im getting quotes of around £120 each hence my looking at putting in new units. As its only the foam surround on the bass unit Ive managed to find someone who will tackle it for me the biggest problem is getting the right parts.
Is it worthwhile to upgrade all the capacitors on the crossover, does it give a marked improvement?
Thanks for your advice

Dave

scott fitlin
07-28-2010, 02:27 PM
Im getting quotes of around £120 each hence my looking at putting in new units. As its only the foam surround on the bass unit Ive managed to find someone who will tackle it for me the biggest problem is getting the right parts.
Is it worthwhile to upgrade all the capacitors on the crossover, does it give a marked improvement?
Thanks for your advice

DaveWait a second, you're telling me they want 120 British Pounds "JUST" to refoam the woofer? I thought that would be a price for a COMPLETE recone. I think that if a service center wants 120 pounds just to refoam the surround, they are quite high on their labor charge.

Is it worthwhile to re-cap your crossover networks? Use the search feature to find crossover recapping, modification, and also charge coupled crossovers. You can read about and see others crossover projects here on this forum. There have been many, with mixed results. Some have had TREMENDOUS improvements, others have gotten results that were not as good as what they originally had, and some say they heard no difference.

MY opinion on whether it is worth it to do is that when dealing with components that have 20 years or more on them, THEY DO DRIFT, meaning that over the years, and with use, their values are not what they were when NEW and within their useful operating lifespan. But, like just about everything audio, what you replace the caps with, might not sound quite the same as what you take out. So, there is both an artform, and a scientific approach to recapping and getting IMPROVED results. What this means is that some guys, especially manufacturers engineers and designers KNOW what to use with what, to create the MAGIC tone they are looking for. Many guys upgrade to very expensive brands of capacitors made from the finest and exotic materials, but it isn't always just a drop in procedure. Guys that know how to pick caps to go with other upgrade caps they are using, usually are the ones that have the best results.

So, YES it can be VERY worthwhile to recap and upgrade your existing networks, but you will be wise to research this, and ask lots of questions. Fortunately, THIS forum has alot of information and threads about successful projects for you to find out and ask about.