Follow-On From The Manufacturer's List - What Do They Sound Like?

medium jim · « **Reply #40 on:** 7 Nov 2012, 05:10 pm »

Quote from: Hank on 6 Nov 2012, 03:27 pm

medium jim - the 2.7 opp is from an email exchange with Peter Gunn - he does something to them which apparently makes them sing.

Guys, I made an offer on these Acoustat Spectra's on eBay: http://www.ebay.com/itm/181014036842?ssPageName=STRK:MEBOFFX:IT&_trksid=p3984.m1432.l2649
I offered quite a bit lower than the asking price. We'll see...

My guess is that John "Peter Gunn" revamps the x/o, possibly flips the panels on the 2.7's. He probably also built wood frames for them. He does do beautiful woodwork, not sure if it has a positive effect on the sound, but x/o's and flipping the panels do.

The eBay seller of the Spectra's has had them listed before without any takers. The bass may be thin because they haven't been broken in, or did he have the right amp(s) to drive them. He has 48 hours to decide on your offer or it will automatically be rejected.

The fact that the seller hasn't counter-offered would indicate that your initial salvo was too low. My guess is that his price is going to be $800.00 +shipping. This is all an semi-educated guess from my 12 years of selling on eBay. No, I'm not the seller and please don't ask for my eBay Moniker.

The 2.7 was and is a wonderful speaker and would personally opt to go that road, but that is me...YMMV.

Jim

Hank · « **Reply #41 on:** 7 Nov 2012, 08:19 pm »

Thanks for the observation, medium jim. I think PB combines 2 of the 3 sections, wiring them together to make the 2.7 a 2-way. I can make hardwood frames for them.
The eBay seller countered with free shipping, which according to the calculator, would be $279. I won't counter. I think I'd prefer Maggie 2.7's (at least that's my thinking today).
And no, I don't want your eBay moniker

medium jim · « **Reply #42 on:** 7 Nov 2012, 09:34 pm »

Quote from: Hank on 7 Nov 2012, 08:19 pm

Thanks for the observation, medium jim. I think PB combines 2 of the 3 sections, wiring them together to make the 2.7 a 2-way. I can make hardwood frames for them.
The eBay seller countered with free shipping, which according to the calculator, would be $279. I won't counter. I think I'd prefer Maggie 2.7's (at least that's my thinking today).
And no, I don't want your eBay moniker

The 2.7 is a factory 2 way and doesn't have 3 panels. Some prefer 2 way planars over 3 way, especially on the mid-sized models due to simpler x/o's.

The 2.5 & 2.6 are basically the same as the 2.7 except for the fact that the 2.7 is quasi ribbon.

Jim

studiotech · « **Reply #43 on:** 7 Nov 2012, 11:17 pm »

Hey Medium, have you ever seen any posts of freq response plots of before and after Gunning either here or on the planar asylum? Thanks.

Greg

medium jim · « **Reply #44 on:** 7 Nov 2012, 11:35 pm »

Sure haven't...

Jim

Hank · « **Reply #45 on:** 9 Nov 2012, 08:15 pm »

Jim, PB didn't tell me the 2.7's are 3 panels. Here is what he said:
The 2.7 has 3 drivers (sections): regular midbass, a mid which uses the old tweeter wire and a tweeter which uses the new QR foil.
He said there's no need to have a separate mid, so he joins it back into the QR foil section to make a single tweeter (which is composed of 2 different materials as a result).
Doing that reduces the speaker back to 2 drivers so it can utilize his XO (which I think is a series XO).

josh358 · « **Reply #46 on:** 10 Nov 2012, 02:22 am »

Quote from: Hank on 9 Nov 2012, 08:15 pm

Jim, PB didn't tell me the 2.7's are 3 panels. Here is what he said:
The 2.7 has 3 drivers (sections): regular midbass, a mid which uses the old tweeter wire and a tweeter which uses the new QR foil.
He said there's no need to have a separate mid, so he joins it back into the QR foil section to make a single tweeter (which is composed of 2 different materials as a result).
Doing that reduces the speaker back to 2 drivers so it can utilize his XO (which I think is a series XO).

Ouch.

medium jim · « **Reply #47 on:** 10 Nov 2012, 03:17 am »

I agree, Ouch!

Jim

Hank · « **Reply #48 on:** 10 Nov 2012, 03:50 pm »

Guys, I don't understand your code Ouch's.

studiotech · « **Reply #49 on:** 10 Nov 2012, 07:33 pm »

I for one, do not trust turning them back into a 2 way without seeing before and after measurements for distortion and freq response. I have heard far too many DIY projects over the years that a done "by ear" alone and sound dreadful. Although, I've never trusted turning them around either without seeing real verified results. Magneplanar makes them, they ought to know best or at least "best for the price charged"

Greg

medium jim · « **Reply #50 on:** 10 Nov 2012, 07:40 pm »

Quote from: Hank on 10 Nov 2012, 03:50 pm

Guys, I don't understand your code Ouch's.

Hank:

The 2.7 was a 2 way, two panel planar, that is why the Ouch. It is obvious that what pg is trying to sell you have been altered to three panels.

This isn't necessarily a bad thing, but as studiotech notes, it would have to be done correctly and with verifiable plot measurements.

Jim

josh358 · « **Reply #51 on:** 11 Nov 2012, 12:03 am »

Quote from: Hank on 10 Nov 2012, 03:50 pm

Guys, I don't understand your code Ouch's.

There's a reason the crossovers were designed as they were. If a driver's width is large compared to the highest wavelengths that it reproduces, it starts to beam, and the power response suffers. Power response is highly correlated with subjective quality, as measured by blind rankings of loudspeakers. By coupling the midrange and tweeter segments, a wide dispersion three-way design is turned into a narrow dispersion two-way design. Furthermore, AFAIK the midrange isn't quasi ribbon, so you lose the advantage of that. Also, you add mass to the tweeter -- a good deal of mass. And by combining the two frequency ranges, you increase intermodulation distortion.

On the plus side, you eliminate a crossover point. But if you want to do that, it seems to me that a platform that's designed from the get go as a two way will give you better results. Also, a single pole crossover has advantages over a higher order one, although again, it's something that generally has to be designed for.

medium jim · « **Reply #52 on:** 11 Nov 2012, 12:26 am »

Well now I'm a bit confused as there might have been two versions of the 2.7. The first a 2 way and the 2nd a 3 way.

I'm posting from my iPhone, or I would post a link to Bullwinkles manual for his 2.7 and one for a review showing them as a 2way.

Google Magnepan mg2.7 and it will show both.

Jim

*Scotty* · « **Reply #53 on:** 11 Nov 2012, 01:47 am »

I find it hard to understand why a functional 3 way design would be turned into a two-way. It is completely unnecessary to do this in order to implement a series crossover. The crossover could be changed to a series network quite easily without asking the tweeter to cover the same frequencies as the midrange.
Scotty

medium jim · « **Reply #54 on:** 11 Nov 2012, 05:33 am »

It appears that I was very wrong about the 2.7's being a 2 way....I assumed that they were a continuation of the 2.6, which were 2 way and went to a quasi ribbon. Turns out they were introduced in 1994 and were 3 way. The confusion to me was that was about the same time the 3 series came into being and were also 3 ways, but with true ribbons.

Sorry for my misinformation and any confusion it may have caused. I hate it when I get egg on my face!!!

I still prefer the 2 way planars due to the simpler and less invasive x/o's required.

Jim

Hank · « **Reply #55 on:** 11 Nov 2012, 03:35 pm »

Quote

It is obvious that what pg is trying to sell you have been altered to three panels.

PG is not trying to sell me a pair - he was just telling how he modded a pair to him they really improved and were very special.
It appears that this 2-panel 3-way model 2.7 was short-lived - maybe because it was so close in performance to the higher-priced 3 series?
Looks like you guys would recommend a 1.6 over the 2.7. Then the series crossover with primo components.
As always, thanks for your continued input

medium jim · « **Reply #56 on:** 11 Nov 2012, 04:27 pm »

Hank:

Read my last post, I was wrong about the 2.7's being originally 2 ways!

Jim

Hank · « **Reply #57 on:** 11 Nov 2012, 10:20 pm »

Jim,
I did read your correction post before I posted the above.

medium jim · « **Reply #58 on:** 11 Nov 2012, 10:38 pm »

My 2.5's are superior to my prior 1.6's. My recommendation would be a pair of 2.5's or 2.6's if they become available. Both have true ribbons and are 2 way. Jim Whiney called the 2.6 the best speaker he made, if you believe the 2.6 review where that was stated.

Jim

josh358 · « **Reply #59 on:** 11 Nov 2012, 10:46 pm »

Quote from: Hank on 11 Nov 2012, 03:35 pm

PG is not trying to sell me a pair - he was just telling how he modded a pair to him they really improved and were very special.
It appears that this 2-panel 3-way model 2.7 was short-lived - maybe because it was so close in performance to the higher-priced 3 series?
Looks like you guys would recommend a 1.6 over the 2.7. Then the series crossover with primo components.
As always, thanks for your continued input

Yes, it's my understanding that the 2.x's were too close to the 3.x's.

I'm not sure why you'd take a 1.6 over a 2.7, though. I'm not sure how they compare but it isn't a done deal that the former will sound better than the latter. In general, a bigger Maggie will have more bass, higher output, lower distortion, better imaging, and better power response/dispersion. The only advantage I can see -- technically -- to the 1.6 is that it's quasi ribbon to a lower frequency. But, of course, that's just what's on paper, what really counts is the actual sound and I haven't heard the 2.7's so can't compare.