HELP-Maggie IIIa's are crackling at high frequency


I have newly refurbished IIIa's. The refurbishing was done by a trusted third party tech. I noticed the high frequency once before when using my Nuera 3300pp integrated but only on ONE record so I chocked it up as a flaw in the record. But just this weekend I went up to a AR V70 power amp and an AR SP-6b pre and its more prevalent than ever. I am not a "loud" listener and I here this "crackling" on the high end of classical female vocalists the most. I have read that people push the maggies as far as to blow the fuses before they get any distortion. This amp combo sounds like it would blow me away but I can't hear past the distortion! Any advice would be awesome and much appreciated, Thank you.
sonorous1

Showing 1 response by magfan

First, the ribbon, in Maggiespeak, is a 'fuse protector'.
The OTHER thing about ribbons is to PROTECT them during shipment. IF you don't have them, Magnepan will sell you some 'ribbon protectors' for shipping. USE THEM. Ribbons are fairly delicate and a blast of wind can wreck 'em. The Magnepan rebuild kit has 3 new ribbons....for a pair of speakers and one to wreck during the 'learning experience'.

Fixing wire delam is less of a hassle these days if you ignore 3M77 and use DAP.
Several fix it people have had great luck. Cleaning first with Acetone is still the only way to get the old glue totally off the panel and wire.

I'd recommend reposting over on the 'planar asylum' of AA. These guys are good and there are several real pros.

IF you can't, by putting your ears near the panel, identify where the wire or ribbon may be bad, I'd find a little more juice for the panels. Bifwynne is 100% that 62 watts is on the low side.
And, though maggies are generally NOT a 'bad load', having moderate phase angles, they are low impedance which places a premium on a good amp.
Maggies and tubes? It can work, but at higher powers.

If all else fails? Get on the phone to Magnepan. Wendel will answer your questions, maybe. The don't have internet since the workforce in WhiteBear Lake is actually working, not messing with computers......like ME.