Sonic Craft Magnepan MG1.6QR External Crossover Modification

earlmarc · « **on:** 16 Oct 2005, 06:16 pm »

Next month I will be shipping my MG1.6QR speakers to Sonic Craft for external crossever mods. I have been searching for about a year now for someone with expertise on modifying my speakers. Sonic Craft has extensive experience with modifying Maggies. They are reasonable with prices depending on the extent of the mod. Jeff at Sonic Craft went over every aspect of the mod. with me and answered all of my questions. I will provide details of the mod. and final cost once completed.

dawkimi · « **Reply #1 on:** 16 Oct 2005, 08:55 pm »

Hi earlmarc,

Please keep us posted on how the mods work out. I have a pair of 2.6R that I would potentially want to have modified. Thanks for your time and assistance.

Mike

Florian · « **Reply #2 on:** 16 Oct 2005, 09:18 pm »

Another really great improvment is to drive them actively.

NealH · « **Reply #3 on:** 16 Oct 2005, 11:41 pm »

Yes, as "Florian" has mentioned an active approach works well with Maggies, especially the 3.6. There is a company on his side of the fence that makes and sells these crossovers. The 3.6 model is reported to sound virtually indentical to the 20.1 except maybe for the lowest register using this active approach. Of course it takes 4 channels of amplification.

http://www.magnepanstudio.de/Magneplanarstudio-uebersicht.htm

But, for the 1.6 the passive mod works well too. It's a bargain of a speaker.

ryno · « **Reply #4 on:** 16 Oct 2005, 11:47 pm »

I bought parts from Jeff for my MG12's. Caps coils and posts. Great guy to deal with, great parts. Ryan

beatdownvictim · « **Reply #5 on:** 17 Oct 2005, 12:46 am »

ryan, i got MG12's recently, and i'm driving them with a panasonic receiver, not great at all. I was wondering what mods you did to your mg12? i'm trying to achieve sonic bliss, but what are some mods i can do for my set of mg12's?

ryno · « **Reply #6 on:** 17 Oct 2005, 03:29 am »

Hey Beat
#1 get them vertical, leaned back on stock stands is bad. If you can afford mye stands or sound anchors all the better. I built mine from home depot parts. I thought the upgraded xover from sonicraft was worth the couple hundred bucks. Enough improvement that I'd love to go active someday. Everyone says positioning is so important, and an inch here or there makes a huge difference. I've found that as long as they're far enough away from the front wall, 3-4 feet, small movements don't make as much difference as when closer. Diffusion on the front wall helps alot, I have heavy drapes on the whole wall. Finally, power power power, Some swear by mid power tube amps, I've never tried, but every ss amp I tried, the beefier the power supply, the higher the reserves, the better it sounded. From yamaha receiver to NAD, rotel, to bryston. Next is a ucd digital, I have high hopes for that.
Weren't you talking a while ago about using a teac for maggies?
Ryan

andyr · « **Reply #7 on:** 17 Oct 2005, 03:41 am »

Quote from: rnhood

Yes, as "Florian" has mentioned an active approach works well with Maggies, especially the 3.6. There is a company on his side of the fence that makes and sells these crossovers. The 3.6 model is reported to sound virtually indentical to the 20.1 except maybe for the lowest register using this active approach. Of course it takes 4 channels of amplification.

http://www.magnepanstudio.de/Magneplanarstudio-uebersicht.htm

But, for the 1.6 the passive mod works well too. It's a bargain of a speaker.

Nono ... it takes 6 channels of amplification to drive 3.6s (and 3.5s/3.3s/IIIAs/IIIs) fully active. THIS is the only way to fly IMO!

Regards,

Andy

earlmarc · « **Reply #8 on:** 17 Oct 2005, 03:54 am »

Explain the active approach please?

andyr · « **Reply #9 on:** 17 Oct 2005, 04:27 am »

Quote from: earlmarc

Explain the active approach please?

I look at it this way ... the 3-way Maggies consist of 3 drivers "connected" by a passive crossover so they can be driven by 1 or 2 stereo amps. The way they are configured is that there's an "external" crossover in a little box which provides the bass LP/mid HP crossover. The mid LP/ribbon HP crossover is done "on-board" - ie. the crossover components are glued to the panel, below the drivers.

Although the external crossover has 2 prs of binding posts, there is questionable benefit in driving it with 2 amps in a "passive biamping" configuration. However, if you replace this passive crossover with a 2-way active crossover (plus a second stereo amp), you get a great benefit IMO.

This can be easily done without "attacking" the speaker in any way. The LP output from the active crossover goes to the bass driver connectors; the HP output goes to the mid/ribbon connectors. Better active crossovers would give you a choice in terms of crossover slopes and frequencies - a common one is to use 24dB L-R instead of the stock slopes.

Very few Maggie owners dispute that this gives a great improvement over the passive crossover ... however, I maintain just as much of an improvement again can be gained by going to a 3-way active setup - ie. removing the internal passive mid LP/ribbon HP crossover. However, this does require you to unsolder wires etc. so those who are more interested in resale value than sonic nirvana don't go there!

The only issue in going 3-way active is making sure you have an amp on the ribbon which does NOT have a "power-on thump" ... otherwise you might blow your ribbons apart (as the drivers are directly connected to the amps - whereas, in a passive setup, they are "protected by the passive crossover components!).

Regards,

Andy

beatdownvictim · « **Reply #10 on:** 18 Oct 2005, 08:01 am »

Quote from: ryno

Hey Beat
#1 get them vertical, leaned back on stock stands is bad. If you can afford mye stands or sound anchors all the better. I built mine from home depot parts. I thought the upgraded xover from sonicraft was worth the couple hundred bucks. Enough improvement that I'd love to go active someday. Everyone says positioning is so important, and an inch here or there makes a huge difference. I've found that as long as they're far enough away from the front wall, 3-4 feet, small movements don't make as muc ...

Yep ryan, that's me. I screwed the mmg-w idea, got a set of MMG's then got a good deal on MG12's. So that's what i have now. Excellent speakers, but i just wanna squeeze a lil more outta em. Thanks for the heads up ryan. I'll look into the Xover mods from sonicraft

Florian · « **Reply #11 on:** 18 Oct 2005, 10:44 pm »

The 3.6 is technically a 2 way speaker

There is one big maylar foil which plays the mids and bass and then you have a ribbon tweeter. You just need an active crossover, which splits them into the bass section and the mid/tweeter section. So you need either 2 Stereo amps or 4 channels. The 20.1 is pretty much the same exept that they use a QR ribbon (twice the width as the 1.6) for the mids which is on the main foil.

You can find a great explenation here www.magnepanstudio.de under Aktiv

Cheers

andyr · « **Reply #12 on:** 19 Oct 2005, 10:54 am »

Quote from: Florian

The 3.6 is technically a 2 way speaker

There is one big maylar foil which plays the mids and bass and then you have a ribbon tweeter. You just need an active crossover, which splits them into the bass section and the mid/tweeter section. So you need either 2 Stereo amps or 4 channels. The 20.1 is pretty much the same exept that they use a QR ribbon (twice the width as the 1.6) for the mids which is on the main foil.

You can find a great explenation here www.magnepanstudio.de under Aktiv

Cheers

Florian,

Sorry, irrespective of what some Dickhead says on the Web, the 3.6 is a 3-way speaker - ie. it has 3 separate drivers. Yes, the bass driver and the mid-range driver are physically located on the same sheet of mylar but they have their own individual wire loop. Then there is the ribbon, which IS physically separate.

The way these speakers are configured is that there is an "outboard" bass LP/mid HP crossover but the mid LP/ribbon HP crossover is "onboard" - ie. glued to the base of the Maggie frame.

Most III/IIIa/3.3R/3.5R/3.6R and 20/20.1 owners never do away with the onboard mid LP/ribbon HP passive crossover ... they just substitute a 2-way active for the "outboard" crossover unit. Hence the confusion which you read about in that Web article.

If you really want to take one of these speakers to its ultimate level of performance, you remove ALL the passive crossovers and tri-amp! This is how I run my IIIAs 3-way active - ie. I have 6 monoblocks.

Regards,

Andy

Florian · « **Reply #13 on:** 19 Oct 2005, 11:10 am »

Oh, i didnt know that. So does the 3.6 use a QR ribbon driver as the midrange section? I never saw one on the 3.6, just on a open 20.1

Well, life and learn.

-Thanks

andyr · « **Reply #14 on:** 19 Oct 2005, 12:18 pm »

Quote from: Florian

Oh, i didnt know that. So does the 3.6 use a QR ribbon driver as the midrange section? I never saw one on the 3.6, just on a open 20.1

Well, life and learn.

-Thanks

Sorry, Florian,

I'm not 100% sure about the 3.6 but I do know that its mid-range driver is slightly different to the preceeding models and is described as a "QR ribbon" ... the same as the 20.

The 20.1 has a "push-pull mid-range QR driver" ... probably this means that the mylar sheet (with the wires glued to it) is enclosed between two metal-sheet-magnets - hence "push/pull" - whereas the 3.6/20 only have the metal magnet array on one side, like the preceeding models.

Regards,

Andy