[lion_heart190]

Hello, anyone out there? :wave:
Google search brought me here and I signed up because I am extremely frustrated.
A few years ago I re-foamed my Cerwin Vega DX-3 floor-standing loudspeakers. I did not remove the dust caps and I think I followed the instructions to a T. After the repair was done and I hooked them up, there was pretty much no bass and the sound was scratchy and weak.

Unfortunately I didn't follow up due to life changes and I pretty much ignored big sound for a number of years. Recently moved and want to get my private listening station up and running again, but my Vegas are still shot. There are no holes, the cones are sound, the cabinets as flawless as the day I bought them, and I can see no outward signs of damage. The Monster cables are intact. I have looked inside the cabinets, stared at the crossovers and tapped the cones. Wires seem ok. Obviously, I have no idea what I'm doing, desperately need help getting these speakers going.
Have tested them with 2 different receivers, and have also hooked up a set of smaller speakers just to make sure the rest of the equipment is working properly. The problem seems to lie squarely with my speakers.

Any ideas?

 

[Wayne A. Pflughaupt]

If the bass sounds weak, that’s typically an indicator that you reversed the polarity of the speaker wires on one of the woofers. Sure fire proof of that would be panning the amp’s balance control to one side and listening to one speaker only. If the bass increases, then that’s the culprit.

OTH, if you have a scratchy sound, that indicates that you did not get the cone lined up properly on the voice coil. Easy mistake to make. If that’s the case, it will require re-doing the surrounds.

Regards,
Wayne

 

[lion_heart190]

Thanks for your reply!
I did reverse the wires every which way and no change to the sound. So now for your next suggestion: how is that done (lining up the cone on the voice coil)? 'Splain it to me like I was a 6 year old. I won't hesitate to tackle this repair again.
Thanks

 

[lion_heart190]

wow

 

[Wayne A. Pflughaupt]

Imagine the speaker cone and voice coil the as a large cup sitting over a smaller one. The larger cup must be centered so that it does not touch the smaller cup underneath. If it does, that’s when you get the scratchy sound.

You’ll probably have to fully remove the new foam surround and start from scratch with a new kit. Once you get the new surround glued to the speaker cone, let the adhesive dry overnight.

After this you will apply the glue to both the back of the surround edge, and the speaker frame. After this is done, spread your fingers evenly around the speaker cone up and move it up and down, and back and forth (or, left to right if you will). You should be able to feel and hear when the speaker cone (i.e. the “large cup) is rubbing against the voice coil underneath (“small cup”). So, position the cone so that it moves up and down freely as you press, without rubbing against the voice coil. At that point you can press the edge of the surround all around the speaker frame, and let the adhesive set overnight.

You should be good to go then. If the still sounds bad, you probably have a bad crossover.

Regards,
Wayne A. Pflughaupt