Question for Steve Burger

[eibei]

Hi Steve:::

Just a quick question. Can the front-outer pole piece for an 802D driver be removed. The driver must have been dropped [no sign of where it was hit]. One side of the gap is to small - the voice coil can not be installed.

Thank you in advace.

Lynn [an Altec bug]

[dennis gilliam]

I've come across many drivers in the same predicament. I use a pair of old butter knives (no sharp edges to raise burrs) to force the poles apart agin, and had good luck. A stack of thin cardboard spacers helps to hold position during the cussing!

DG

[Jim D]

I'll reply for Steve, I don't think he'll mind. You can try to recenter it yourself. I have used a hardwood dowel and a rubber magnet. Place the end of the dowel on the part of the pole piece closest to the voice coil and tap the other end gently with the mallet. You ought to have the driver bolted down to a vise of table. Check the gap with several sizes of copper wire or soldier. Soldier works well as you can smash it with pliers and get just the right thickness. Start with a size of soldier or wire that fits in the wide part, rotate it until it sticks in the narrowed gap, find the narrowest part, mark with a pencil, tap with the dowel and mallet, check it repeatedly until your wire/soldier gauge fits around the gap uniformly. You will have make several soldier/wire guages as you move the gap. I like the wooden instrument as it doesn't dent the metal. This method doesn't work so well for ceramic magnets as they are very hard to move once set. Please note, that alnico magnets demagnetize with overpowering and somewhat with age. The original whack and the recentering will also demagnetize the magnet, how much I cannot say, it may be significant. The absolute best option is to send it to Bill at GPA and have him recenter and remagnetize the driver. I once recentered a 288, the HF and sensitivity were significantly lower. Alnico drivers can be repeated repaired. Jim

[Jim D]

Oh well, I mean rubber mallet, not magnet, I supose there is one somewhere. Jim