Posted by AntonioJ (A) on September 05, 2014 at 02:52:30

Dear colleagues,
After lurking, reading and learning for some good months, I decided to register and share my experiences with my Magnepans. Hello everyone.
Well, I was happy with my Audio Notes but for that inescrutable reason decided to go for a pair of SMG-as. I've always loved planars since I heard them first many years back. I once owned a pair of Apogees, but both my wife and amplifier -at the time- (and in no particular order) stopped my experiencing futher.

So I got a nice used pair some weeks ago on the bidding site for almost no money, suspected ready for the bricolage.
When the SMGas arrived home I was pleasantly surprised that, even though the cloth was quite worn and the wood trims needed caring, upon doing the upskirt the coils were absolutely perfect: no greening, no lifting…., nothing wrong; only maybe the mylar was a bit sticky had accumulated some dust. I'm keping the original fabric and not doing any restoration of the guts at this stage.
First connection to the amp was disappointing till I discovered that both fuses were cut and no treble was coming from the panels. Also one of them was wired out of phase. ---* follows a NOTE(1) on this
But otherwise the speakers had been admirably taken care of.
I have to thank Paco (group user) for his advice and friendly contact, and following the many advices and wise posts by many of the users here, I took up the crossover modification. I also spoke to Tony Gee of Humblehomemadehifi (thank you!!), and finally went down the following path. I will be brief further on:
- Dismantle the wiring, including the fuse.
- Keep the original scheme for cap and inductance connection.
- Replace original capacitor with 1 x Obbligato Aluminium Foil (47uF) + 1 x Jantzen Superior-Z (3,3uF) + 1 x Vishay MKP1837 (0,01uF) per box more or less totalling the original specs.
- Replace original inductance with 1 x Jantzen Audio WaxCoil (AWG14, 0,68mH, 0,202Ohm) ---* follows a NOTE(2) on this.
- Re-wire without the fuse and resistor with Duelund "foil in silk" cable and DH Labs silver 12AWG wire.
All of the above mounted into a wood box which I have treated for vibration and resonance and that I will fill up with sand (following Paco's advice).
I have added a pair of WBT plugs to connect to the amplifier.

Note(1): ok, my amplifier is a classic valve integrated Audion Sterling ETSE (standing for Extended Triode Single Ended).
Ok, before you think I know beans, let me tell you the SMGs don't need tenths of watts to deliver that wonderful sound they're famous for.
My re-capped amp just puts out 14w of clean, wonderfully refinate watts into the Maggies and because I don't need outrageous volumes, the sound is lush, delicate but full. I don't need more bass.

Note(2): The original inductor should be a 0,78mH (even though it doesn't read so anywhere but in your posts here). I've settled for a 0,68mH one because I did not have any available source at hand at the time.
Does this make a great difference ? I don't have the tech knowledge, and don't feel like rewiring the old stock ones back ! Your advice here will be highly appreciated.
Nice to be here. Greetings from sunny Spain!