[FLEMKE]

Is there a difference between the two? I own a pair of 1.7i's and think replacing the crossovers would give my something to do this winter.

Tim

[Danny Richie]

Is there a difference between the two? I own a pair of 1.7i's and think replacing the crossovers would give my something to do this winter.

Tim

Hey Tim,

I wish you were close by. I'd love to help you with that.

Here is an upgrade I did for the Maggie MMG's: http://www.audiocircle.com/index.php?topic=141550.msg1517919

[FLEMKE]

Danny,
I saw you post about the MMGs. That was why I posted here. I may just have to open them up!
Tim

[I.Greyhound Fan]

Is there a difference between the two? I own a pair of 1.7i's and think replacing the crossovers would give my something to do this winter.

Tim

Just curious, what is it that you do not like about the 1.7i's?  I own the 1.6's and MMG's and have heard the 1.7's. 3.6's, 3.7 and 3.7i's. Maggies are finicky about amps and preamps as well as positioning.  They like lots of high current power.
I use to run my 1.6's with a Parasound A21 and an AVA hybrid tube preamp.  They sounded good but not great,  but when I went to a Pass Labs X250 amp and a BAT preamp they really came alive and sounded so different.

Also, adding a high quality subwoofer makes a huge difference.

[FLEMKE]

I have a BAT VK-75 which is modified. The crossover upgrade makes for a rather impressive upgrade. I have seen a pic of the 1.7 crossovers and they are fairly simple. I guess it's just part of the sickness to try and make it sound better!

Tim

[*Scotty*]

I would advise that you build or buy an enclosure for an external crossover, this gives you maximum flexibility for parts size and placement. If you look closely at the image below of the Maggie 1.7, you will see a 75uF 100volt cap hiding in there, that appears to be a non-polarized electrolytic capacitor. The total value of caps in the cross over if replaced in their entirety with high quality caps will represent a substantial investment. There is no reason to expect that a very different crossover resides in the 1.7i. You should also plan on duplicating the DC resistance of any inductors you replace.

Scotty

[FLEMKE]

Did you get that pic from the Gunn website? I would certainly be taking my time to match things up correctly.

Tim

[*Scotty*]

That's where I pulled the image from.
If you do go outboard with the crossover I would be damn sure I duplicated crossover circuit exactly. The crossover schematic on the Gunn website doesn't make a lot sense to me and there are supposedly some kind of differences between the 1.7 and the 1.7i which remain undisclosed by Magnepan.
 In lieu of deriving a circuit diagram from observation of the crossover network, it might literally be easier to just put extensions on the existing connections from the panel to the crossover and move the entire assembly outboard and replace the components one at a time within the existing wiring harness. Once this was done the wiring between the components could be also upgraded one piece at a time. It would also be a good idea to take a photo of the stock cross over in situ before anything is done as a reference.
Scotty

[Davey]

Everything on the Magnestand website of a technical nature is highly suspect.  Peter Gunn (John) himself doesn't even know what a crossover is, so I would take everything there with a grain of salt.

The newer X.7 speakers are all series crossovers.  You guys are aware of this, yes?  I keep somewhat informed on the modification activities of Magnepan users but I have seen no schematic drawings of these newer speakers that I would 100% believe are correct.  Magnepan is no longer supplying schematic diagrams for their current models, unfortunately.

Regardless, if you want to really improve those speakers you need to remove the whole stock crossover and reconfigure the setup for bi(tri)-amp operation.  Anything else is just turd polishing.  If this is beyond the capabilities of any contributors, I think I would be inclined to just leave well enough alone.

Dave.

[FLEMKE]

I picked up the 1.7i's for a song and have $1500 I can blow on the mods. Chicago winters suck and I need something to keep from going insane!
Tim

[Danny Richie]

Everything on the Magnestand website of a technical nature is highly suspect.  Peter Gunn (John) himself doesn't even know what a crossover is, so I would take everything there with a grain of salt.

Dave.

I would have to agree with this statement from Davey. Really just about everything about the network that is on there is just so very wrong. I really question any of the after market networks for those things that don't include actual measurements from the speakers.

For me to go through them and design a new network for them is a piece of cake, but I would have to have the speakers here.

[FLEMKE]

Danny,
That's a 14 hour drive. You never know. The pic is of the OEM crossover if I am not mistaken.
Tim

[Davey]

I would have to agree with this statement from Davey. Really just about everything about the network that is on there is just so very wrong. I really question any of the after market networks for those things that don't include actual measurements from the speakers.

I'm not talking about acoustic measurements of the speakers.  I'm talking about examining and redrawing the schematic (correctly) into a standard format.  That way you have a proper baseline reference for the electrical transfer function of the network.  Acoustic measurements can come (much) later.

No doubt you would find these speakers would not measure acoustically flat and would not conform to some idealistic response curve you had in mind.  However, that's essentially irrelevant because we don't know what acoustical target the Magnepan guys had in mind.

The 1.7's have been pretty much universally praised, so either the Magnepan guys pretty much know what they're doing or they got pretty lucky.  I think it's probably the former. 

Dave.

[Danny Richie]

Davey,

From what I have seen of their designs I am not sure they have an acoustical target. The SMG model that I measured a few weeks ago was beyond help. The tweeter levels were significantly down compared to the mid panels. Nothing about the response of that model looked anything like the MMG's that I had in here a few months ago. 

And I don't see a lot of high praise being bestowed on a speaker with internals at this level of quality (or lack there of).



I honestly can't look at that and say to myself that these guys really know what they are doing.

They make some nice panels though and I believe that it is not hard to take them up the performance ladder by a LOT and in many areas.

[Davey]

Just because you don't know what it is, doesn't mean they don't have an acoustical target. 

The praise for this speaker comes from listeners/owners/reviewers that probably haven't seen the internals, nor would they care what they looked like.
Clearly Magnepan doesn't prioritize component selection and workmanship in the same way you do, but that doesn't necessarily mean they don't know what they're doing.

I've listened to a set of 1.7's extensively in a nice room.  For what they are, they're excellent speakers....stock.

Dave.

[Danny Richie]

What I mean by saying I don't know what their acoustic target is comes from measuring various models and seeing no real pattern at all. It looks to me that they design them from an electrical standpoint rather than any acoustic response.

And anyone that is interesting in improving them is going to to have a look inside. And anyone with any experience with speakers will recognize a lot of room for improvement in that department.

[bdp24]

Everything on the Magnestand website of a technical nature is highly suspect.  Peter Gunn (John) himself doesn't even know what a crossover is, so I would take everything there with a grain of salt.

The newer X.7 speakers are all series crossovers.  You guys are aware of this, yes?  I keep somewhat informed on the modification activities of Magnepan users but I have seen no schematic drawings of these newer speakers that I would 100% believe are correct.  Magnepan is no longer supplying schematic diagrams for their current models, unfortunately.

Regardless, if you want to really improve those speakers you need to remove the whole stock crossover and reconfigure the setup for bi(tri)-amp operation.  Anything else is just turd polishing.  If this is beyond the capabilities of any contributors, I think I would be inclined to just leave well enough alone.

Dave.

Dave, is that your pair of Eminent Technology LFT-8b's for sale on U.S. Audiomart right now? IMO a better speaker than the MG 1.7i, and at a price cheaper than new 1.7's. The LFT-8 comes from the factory bi-ampable, unlike the 1.7.

[bdp24]

Just curious, what is it that you do not like about the 1.7i's?  I own the 1.6's and MMG's and have heard the 1.7's. 3.6's, 3.7 and 3.7i's. Maggies are finicky about amps and preamps as well as positioning.  They like lots of high current power.
I use to run my 1.6's with a Parasound A21 and an AVA hybrid tube preamp.  They sounded good but not great,  but when I went to a Pass Labs X250 amp and a BAT preamp they really came alive and sounded so different.

Also, adding a high quality subwoofer makes a huge difference.

The GR Research OB/Dipole Subwoofer is THE sub for the 1.7, as well as all other dipole loudspeakers.

[Davey]

Dave, is that your pair of Eminent Technology LFT-8b's for sale on U.S. Audiomart right now?

Yes.  In fact, those are improved from stock since I addressed the HF resonance of the woofer driver by modifying the network.  The ET's are better than Magnepan's in some ways, but fall short in others.  However, I could live with either speaker long term.

Dave.

[Davey]

What I mean by saying I don't know what their acoustic target is comes from measuring various models and seeing no real pattern at all. It looks to me that they design them from an electrical standpoint rather than any acoustic response.

Nope, I think the opposite is closer to reality.  In fact, the majority of the Magnepan models have electrical design that have no relation to any kind of targeted response.  The raw acoustic response of the drivers themselves completely eliminates that (possible) approach.

If you'd like to see some designs from an electrical standpoint rather than an acoustic response, take a look at the Magnestand efforts. 

Dave.