Damn these Magnepan SMGa's !!!!

[onwardjames]

Hello, all !!

An Ak'er was kind enough to give me a pair of these legends a year or so ago, with the caveat that there was a sizable rip in the mylar, and occasionally, the tweeter on one with the rip would cut out.

After not connecting them for the past year, I got around to it.

Yep, they have a rip. Yep, they cut out on the highs. Yep, I LOVE this sound (when it works).

I've resigned myself to buying a new pair some day, but have tried, with no appreciable success, to locate just why this tweeter keeps dying.

It takes at least 3/4 volume on a 130 wpc amp to get the tweeter to come to life. Go below that, it almost never stays on. I've looked for tears or breaks in the wire, I see nothing. I've manipulated and cleaned and massaged the fuse holder, no luck. The tweeter simply comes on when it wants, usually at near-deafening levels.

Anyone have any tips?? Will the new LRS Magnepans that everyone raves about best these old girls??

Thanks for any and all advice and suggestions. I see the allure of planar. It's really special.

 

[MuseChaser]

A shot in the dark...is there a jumper on the input/crossover panel? If so, remove it, clean it and the contacts to which it connects, then put it back in place.

And....regarding the special allure of planars....yes. Yes, there most definitely is. Welcome!

 

[onwardjames]

A shot in the dark...is there a jumper on the input/crossover panel? If so, remove it, clean it and the contacts to which it connects, then put it back in place.

And....regarding the special allure of planars....yes. Yes, there most definitely is. Welcome!

Hello to you as well !!

No jumper, just a fuse holder. I removed the fuse completely, and the tweeter part was still cutting in and out. I am not sure how THAT happens. I've cleaned and flexed it ad nauseum.

I tried reflowing the solder everywhere, but I need one of those heavier soldering irons. This little bench one isn't too strong.

It is baffling.

I have read about those LRS, as well as the 1.7i offerings from Magnepan. I will one day own one of these pair, I hope.

It'd be great if I could only get these working. The tear doesn't matter, I'm using a sub to take most of the flex out anyway.

 

[Blue Shadow]

I tried reflowing the solder everywhere, but I need one of those heavier soldering irons. This little bench one isn't too strong.

The soldering is aluminum solder. Different animal. Need to use aluminum soldering material.

Maybe some used LRS will show up on the market with the release of the LRS+.

I'd be looking at the nudes and check the wiring from the input panel through the crossover and the voice coil on the mylar back to the jack. Check each connection for any looseness or intermittent possibilities. White spots on the wiring are corrosion and can destroy the wires. Had a couple pair come through like that. Full rewire needed unless it is an isolated spot.

The mylar rip can be repaired with scotch tape. I use the scotch packing tape as it is thicker and has good adhesive on it. Of course, moving the wires out of the way would be necessary but that shouldn't be impossible. Adhesive gives up easily to acetone and then after the tape is added, reglue using any of the choices discussed on the MUG site.

Maybe just putting tape over the wires would work to keep the panel from flexing to the point of a problem.

 

[E-Stat]

In the late 70s when I was a teen, one of my mentors was Dr. Cooledge (JWC) of TAS. It was his Dayton-Wright electrostats that turned me into a believer.

One of the panels needed to be replaced and they employed a unique approach to running very high bias levels - the cabinet was sealed with an outer diaphragm and filled with SF6 - an electrical insulating gas.

I assisted with the surgery. We had to slit the outer diaphragm for access and once complete, mended the tear with thin packing tape. Then used a hair dryer for retensioning. Short of having a factory repair, mylar can be fixed.

And yes, the LRS are a good bit more transparent.

 

[onwardjames]

The soldering is aluminum solder. Different animal. Need to use aluminum soldering material.

Maybe some used LRS will show up on the market with the release of the LRS+.

I'd be looking at the nudes and check the wiring from the input panel through the crossover and the voice coil on the mylar back to the jack. Check each connection for any looseness or intermittent possibilities. White spots on the wiring are corrosion and can destroy the wires. Had a couple pair come through like that. Full rewire needed unless it is an isolated spot.

The mylar rip can be repaired with scotch tape. I use the scotch packing tape as it is thicker and has good adhesive on it. Of course, moving the wires out of the way would be necessary but that shouldn't be impossible. Adhesive gives up easily to acetone and then after the tape is added, reglue using any of the choices discussed on the MUG site.

Maybe just putting tape over the wires would work to keep the panel from flexing to the point of a problem.

In the late 70s when I was a teen, one of my mentors was Dr. Cooledge (JWC) of TAS. It was his Dayton-Wright electrostats that turned me into a believer.

One of the panels needed to be replaced and they employed a unique approach to running very high bias levels - the cabinet was sealed with an outer diaphragm and filled with SF6 - an electrical insulating gas.

I assisted with the surgery. We had to slit the outer diaphragm for access and once complete, mended the tear with thin packing tape. Then used a hair dryer for retensioning. Short of having a factory repair, mylar can be fixed.

And yes, the LRS are a good bit more transparent.

Two very helpful posts. Thank you, gents.

What does it mean to have aluminum solder?? Do I need a different iron?

 

[djnagle]

They are certainly worth fixing.

https://www.diyaudio.com/community/threads/diy-magnepan-smga-repair.127336/

 

[Blue Shadow]

The aluminum wires are soldered with a different solder and regular solder won't work to the level Magnepan needs it to. They supply a chunk of solder with their rebuild kits. Aluminum solder needs a clean iron and when done the iron needs to be cleaned again to remove the solder before going back to regular 63/37 solder.

I'd need to surf the web to figure it all out again but there are folks that have gone through the issues and bought supplies for this work, other than what Magnepan supplied.

 

[wmgwizard]

I have a separate tip for my iron that I use on aluminum wire / solder. Nothing special, just specific, takes about a minute to swap.

 

[a_retent]

Anyone have any tips?? Will the new LRS Magnepans that everyone raves about best these old girls??

Sorry I haven't any mylar repair tips for you other than what's already been mentioned. However I would like to offer a possibly more affordable alternative to LRSs and that would be the MMGs. In my experience even the MMGs will "best" your SMGs and cost less than a pair of LRSs.

I bought my used pair of MMGs locally with everything in the box for 3 Benjamins and a Grant.

 

[The Fuxtor]

ive had both and the mmg model were awesomer!!

 

[CraigVMN]

Magnepan is one town over from me, toured the place some years ago

 

[Ross6860]

Hello, all !!

An Ak'er was kind enough to give me a pair of these legends a year or so ago, with the caveat that there was a sizable rip in the mylar, and occasionally, the tweeter on one with the rip would cut out.

After not connecting them for the past year, I got around to it.

Yep, they have a rip. Yep, they cut out on the highs. Yep, I LOVE this sound (when it works).

I've resigned myself to buying a new pair some day, but have tried, with no appreciable success, to locate just why this tweeter keeps dying.

It takes at least 3/4 volume on a 130 wpc amp to get the tweeter to come to life. Go below that, it almost never stays on. I've looked for tears or breaks in the wire, I see nothing. I've manipulated and cleaned and massaged the fuse holder, no luck. The tweeter simply comes on when it wants, usually at near-deafening levels.

Anyone have any tips?? Will the new LRS Magnepans that everyone raves about best these old girls??

Thanks for any and all advice and suggestions. I see the allure of planar. It's really special.

I'll put it this way, I tried the LRS on the 60-day free trial. I sent them back. They got me hooked.

I then purchased a pair of 1.7i which still live in my "main system".

The LRS were that impressive I had to try something up the line. The new LRS+ is supposed to be even better.

FWIW, I could have kept the LRS and just added a pair of subs. So now I have the 1.7i, and a pair of subs. I'm not looking for any other large speakers. I'm pretty satisfied.

No bass slam, or ear-splitting cannon shots, but imaging, sound-stage, and mid-range are wonderful. You just need some room to set them up.

They bested Infinity RS-II, Kappa 7.1 S2, RS-IIIa, AR-3a, NS-690. They are all gone. Just my two cents.

 

[a_retent]

Magnepan is one town over from me

We must be neighbors, I'm one town to the south of them.
Like you, I got an impromptu tour of the place when acquiring parts for my 1.6QRs...even got the t-shirt.

 

[onwardjames]

Following up my thread....

Never did figure out what causes one speaker to fail to work until the volume on my 130 wpc Yamaha is nearly at 11 o'clock. Took them out of rotation until another time presents itself.

Anyone have any comments about the LRS Magnepans (which I hear are great!) and the 1.7i's (which may be too much speaker for my 10x10 room) ??

All comments appreciated.

 

[onwardjames]

I'll put it this way, I tried the LRS on the 60-day free trial. I sent them back. They got me hooked.

I then purchased a pair of 1.7i which still live in my "main system".

The LRS were that impressive I had to try something up the line. The new LRS+ is supposed to be even better.

FWIW, I could have kept the LRS and just added a pair of subs. So now I have the 1.7i, and a pair of subs. I'm not looking for any other large speakers. I'm pretty satisfied.

No bass slam, or ear-splitting cannon shots, but imaging, sound-stage, and mid-range are wonderful. You just need some room to set them up.

They bested Infinity RS-II, Kappa 7.1 S2, RS-IIIa, AR-3a, NS-690. They are all gone. Just my two cents.

Thank you for this, albeit a bit late on my part. I may just gun for a set of the LRS+

 

[wmgwizard]

I found a corroded fuse holder once that caused a simar issue......had to send enough juice to overcome the additional resistance.

Not sure if your speakers have fuses but it might be worth a peek ?

 

[onwardjames]

I found a corroded fuse holder once that caused a simar issue......had to send enough juice to overcome the additional resistance.

Not sure if your speakers have fuses but it might be worth a peek ?

Yes, they have fuses.

Man, I cleaned and worked that thing over and over. Swapped the fuses. Reflowed solder. Still does the same stuff.
Doesn't appear to be that. Thanks for the heads up, tho.

 

[wmgwizard]

Sorry, I didn't know you had already been down that road.

 

[Thefamous]

Only working with a lot of power is almost certainly a bad connection somewhere. If you have a multi meter set it for continuity (the beep setting) and work your way thru the wiring until you find it.

In a perfect world that should work. In the real world hopefully too, but you never know. At least it’s not the other way where it occasionally drops out. That is much harder to chase down. Good luck!