Bolivar Model 64 Speakers

[Nodieskys]

Yes that is a classic symptom. Especially if pushing in one area of the cone makes it worse, and/or pushing elsewhere makes it better or disappear. The voice coil is wrapped on a short cylindrical piece like toilet paper roll, and it sits in a narrow gap between the outer magnet and inner pole piece. If it's off center it will rub, sound bad and eventually wear through the voice coil wire. This driver may have a narrow VC gap, or it may just be a bad refoam job. I have never shimmed when doing a refoam but it sounds like maybe you should on this one. Actually I had one this spring that started rubbing at high volume, so I may have to get into shimming myself. It's a PITA but it's also a guarantee.

Hello guys dose anyone know the measurements of the boxes of model 64 ??

 

[Woodness]

Did you shim the voice coils? Like I stated earlier, they are tight, doubt you could get lucky enough with test tone, etc. I did try the ol' rotate 180 and it did not help me either.
Good luck!!

No. I have no idea what to do in that respect. Might have to get them to a pro.

 

[toxcrusadr]

Sounds like it is either way off center during a refoam, or the voice coil former itself is out of shape and rubbing no matter what you do. That's usually the result of overdriving. When the speaker hits overexcursion on a heavy note, the back end of the voice coil former (imagine the end of a cardboard toilet paper core) hits the magnet in the back, which deforms it, and how it hits the walls. JBL was known for narrow voice coil gaps for the VC to ride in, so it is easy for this to happen.

 

[Woodness]

Sounds like it is either way off center during a refoam, or the voice coil former itself is out of shape and rubbing no matter what you do. That's usually the result of overdriving. When the speaker hits overexcursion on a heavy note, the back end of the voice coil former (imagine the end of a cardboard toilet paper core) hits the magnet in the back, which deforms it, and how it hits the walls. JBL was known for narrow voice coil gaps for the VC to ride in, so it is easy for this to happen.

Can that be repaired?

 

[Woodness]

Hello guys dose anyone know the measurements of the boxes of model 64 ??

14” x 12” x 26.5”

 

[toxcrusadr]

Once a VC gets deformed, my impression is it is not very repairable other than replacing the voice coil or the entire VC/cone assy, assuming a suitable replacement can even be found.

An off center refoam can be fixed by refoaming, with shims.

 

[ramzilla]

No. I have no idea what to do in that respect. Might have to get them to a pro.

Plenty of info on this website, or see YouTube about shimming voice coil for refoaming. Not that hard to accomplish.

 

[Woodness]

Plenty of info on this website, or see YouTube about shimming voice coil for refoaming. Not that hard to accomplish.

Thanks, I did the refoam myself. Looked up shimming and it doesn’t seem too bad after all, if I can find the time.