[SteveFord]

Wendell sent me an email today which I'd like to pass along.
I'm so tempted to add that they must have spiked the water cooler at work but I won't.
Here it is:

I don't follow the chat rooms to know if this idea has been suggested--
The urge to modify and be a Weekend Engineer may be an itch that never goes away. Is your latest crossover mod really better or just different? Would you really want to conduct a blindfold test with a panel and find out? Probably not. It is VERY discouraging.

There is a vast pool of used Maggies after 43 years in need of some TLC. Do you have some friends or family with limited resources that would appreciate a rebuilt pair of Maggies? It is not cost effective to ship some of these old Maggies back to Magnepan for repair and refurbishing. Besides, Sue has too much work as it is.

Do something good for someone else and satisfy your tweaking urge at the same time---which is essentially what we do here at Magnepan. We design and build cool toys that enrich the lives of others. For that we make a modest living---all very rewarding.


This is me again - no way.  I hate glue and I hate wood and they both hate me back. 

[andyr]

Wendell sent me an email today which I'd like to pass along.

There is a vast pool of used Maggies after 43 years in need of some TLC.
Do you have some friends or family with limited resources that would appreciate a rebuilt pair of Maggies?
It is not cost effective to ship some of these old Maggies back to Magnepan for repair and refurbishing. Besides, Sue has too much work as it is.

Don't quite understand what Wendell is trying to say, Steve? 

Is he saying there is a vast pool of Maggies at Magnepan, which need some TLC to restore?  In which case why would they pay the shipping costs for sending them out to us, to be restored?

Or is he suggesting we find them by the side of road, restore them and then pass them on?  Ain't none by the side of the road in Oz, I can assure you! 

Would you really want to conduct a blindfold test with a panel and find out? Probably not. It is VERY discouraging.

I challenge Wendell and his panel to come out to Oz and compare (blind), say, my active Frankenpans (same slopes as a stock IIIa, just slightly different -3dB points) against some stock 3.6s - passively driven by, say, a Parasound A21 or a Magtech.
Or, if that's too much trouble, he can instruct his Oz agent to do it for him (and pay him for his trouble, of course  ).

The advantages from having the mid panel on separate sheet of mylar to the bass panel (so you can have 2 frames - 1 for bass & 1 for mid/ribbon - per side) are several, including:
* no IMD between the two drivers,
* vibrations generated by the bass panel do not shake the ribbon cage, and
* drivers are time-aligned ... something you cannot do when all drivers are in a line, in the one frame.

A comparison against 3.7s would also be interesting ... although I'm willing to believe that there's a significant benefit delivered by the QR technology.


Regards,

Andy

[josh358]

Remember thought that it costs them a lot more to make a second frame and driver than to put the midrange and woofer on the same driver in the same frame. It's almost as costly as making two speakers. This is why the 20.7 has a separate midrange driver, while the less expensive 3.7 uses a segment of the woofer driver.

[SteveFord]

I think that what he's trying to say is that you'll save a lot of money (and achieve better results) with modifying the older models which are probably in need of some TLC, anway.
I'll come to Australia if somebody buys me a ticket!

[josh358]

I think that what he's trying to say is that you'll save a lot of money (and achieve better results) with modifying the older models which are probably in need of some TLC, anway.
I'll come to Australia if somebody buys me a ticket!

Definitely the way to go on a bang-for-buck basis, if you have the time.

[SteveFord]

Hey, AndyR,
What part of Australia am I flying in to?
Get your jodpuhrs and pith helmet out of mothballs, we're going python hunting!

[andyr]

Remember though that it costs them a lot more to make a second frame and driver than to put the midrange and woofer on the same driver in the same frame. It's almost as costly as making two speakers.

Correct, Josh.  I understand that's why they stopped making the T-IVa ... 3 frames was just too expensive to make. 

This is why the 20.7 has a separate midrange driver, while the less expensive 3.7 uses a segment of the woofer driver.

Does the 20.7 have a completely separate midrange driver ... or did they mechanically isolate the mid side of the (one) mylar sheet from the bass side, by extending the clamping strip which on IIIas/3.Xs only extends 1/2-way down the mylar, to the bottom?

Either way, the result is the same (no IMD between mid & bass drivers) ... but a completely separate mid driver (which is what you said) would be more expensive.

Regards,

Andy

[andyr]

I think that what he's trying to say is that you'll save a lot of money (and achieve better results) with modifying the older models which are probably in need of some TLC, anway.

No, I don't think he's saying that, at all.     Quoting from his email "Is your latest crossover mod really better or just different? Would you really want to conduct a blindfold test with a panel and find out? Probably not." - this says to me Wendell believes that the XOs that Magnepan build cannot be bettered.

Whereas I would say they certainly can be bettered ... but at a cost which makes it uneconomic for Magnepan to consider doing this!    For the internal XO located on the base of the MDF frame ... how many times more would it cost to:
a) use (much larger) air-core coils (12g ribbon coils, North Creek 10 or 12g Music Coils - take your pick) and "boutique caps", and
b) mount these in an external box so they are not affected by vibrations in the panel frame.

I'd say their manufacturing cost would jump from $30-50 to well over $500 ... which would mean the speaker price would have to go up by a factor of 3, minimum.

Whereas this sort of thing is feasible for a DIYer  - as is replacing the MDF frame with hardwood (lucky are those that have woodworking skill - I had to pay someone to make them for me!  ).

Regards,

Andy

[andyr]

Hey, AndyR,
What part of Australia am I flying in to?
Get your jodhpurs and pith helmet out of mothballs, we're going python hunting!

Melbourne - down south where it's cold!    Pythons are up in the hot north though if you want to come to Oz to go hunting ... I suggest wild pigs ("razorbacks") are what you want. 

Regards,

Andy

[SteveFord]

The gist of his email is that it's cheaper to pick up some oldies to modify than it is to purchase a set of new .7 models to modify.
You can get IIIAs for around $600 while 3.7s are over $5,000.
That's all it was meant to be.
Those prices are for here in the US, I don't know about Australia.

No wild pigs - those things are really dangerous!

[andyr]

You can get IIIAs for around $600 while 3.7s are over $5,000.
Those prices are for here in the US, I don't know about Australia.

I believe 3.7s are A$8K here - about USD8,300.

No wild pigs - those things are really dangerous!

Yeah, I've seen news reports of people shooting them from a small helicopter! 

Regards,

Andy

[medium jim]

I've owned too many speakers and I settled on a pair of 2.5's that I did some delam repairs on, and replaced the ribbons....they already had the x/o's and inductor upgraded.  Best damn speakers I've owned.  Net cost under 1K....even if I had to send them to MN, still would have been around 2K with the shipping, still a bargain.   

I think Wendell was merely saying that it is a good idea to restore the old ones as the overall cost is still low and you will have a restored set of maggies that will bring great pleasure.  I happen to like the sonic signature of the old ones over the newer ones. 

Jim

[josh358]

Does the 20.7 have a completely separate midrange driver ... or did they mechanically isolate the mid side of the (one) mylar sheet from the bass side, by extending the clamping strip which on IIIas/3.Xs only extends 1/2-way down the mylar, to the bottom?

Either way, the result is the same (no IMD between mid & bass drivers) ... but a completely separate mid driver (which is what you said) would be more expensive.

Regards,

Andy

It's completely separate, so they can optimize its properties.

[andyr]

It's completely separate, so they can optimize its properties.

That's good to hear.  I believe (from a pic I saw either here or on the Planar Asylum, from somebody's factory visit) that is an improvement on the 20.1, which had the full-length clamp?

Regards,

Andy

[josh358]

That's good to hear.  I believe (from a pic I saw either here or on the Planar Asylum, from somebody's factory visit) that is an improvement on the 20.1, which had the full-length clamp?

Regards,

Andy

I may be wrong about it. I haven't really heard any details on the 20.7, just that the mass of the midrange has been reduced. How, I don't know, there are a couple of references online but they may not have been reliable.