[TruBrew]

I think it is calling you to try.

 

[jaycalgary]

The 407 Sigmas were a failure no doubt about it. I took a step back and enjoyed the O2 Mk1 I bought at the time. The diy sigmas with lambda pro drivers are not bad at all. I swapped out the mineral wool and replaced it with pure cotton balls that i pulled apart. It was a noticeable improvement for me.The 407 drivers in that new plastic housing sound something like bongos with any tap on the diy housing that I made. I just tore them apart and am going to try and turn them into the old style drivers.

 

[ujamerstand]

Quote:

I think it is calling you to try.

I would if it didn't cost so much. I think it's at least 120 dollars for the two cups. That's a spendy failure if the structure flexes and causes coloration... There's always making the backplate with steel bronze, but I think it's too costly and too heavy. I'll look more closely at it after I'm done with my kgsshv.
 
Bongos. Haha. Is it really that bad? I thought that the way the drivers are mounted in the 407 plastic enclosure means that there'll be less coloration?

 

[scott16]

They show the pic of the top and bottom measurments here.
http://cdn.head-fi.org/0/01/0174078d_sigmapromeasurements.jpg
 
But does anyone know the height of the sides?

 

[moodyrn]

Quote:

 
Bongos. Haha. Is it really that bad? I thought that the way the drivers are mounted in the 407 plastic enclosure means that there'll be less coloration?

Yeah when used in a 407 housing

. I guess it goes to show that you really can't mix new with old.

 

[jaycalgary]

The 407's were scraped it was hopeless because of the hollow sound the 407 drivers gave. I will try again some day with the older drivers because it was a fun project and had those housings as solid as I think they would need to be.

 

[scott16]

I'm trying to make the enclosures (using a slotted Aluminum Grill II bought on Ebay) 
I see this is the top and bottom but does anyone have the side measurements?
 
 
Quote:

Back with some measurements. It's actually not symmetrical. I hope you find this useful:
 

 

[scott16]

the width of the side walls is plain b.c I know the top and bottom dimensions
but the height of the side walls isn't clear, does anyone know it?, It would be the same height for all of them.

 

[jaycalgary]

I have been listening to a factory pair of Sigma pro's for a week or so. Sure gave me the itch to make a new pair. I have read the people like how the 303 drivers sound so I will try to find a pair. It sure won't be any of the new type drivers. It is going to take me a while to build being away busy with work but I think I have a great idea. It is not really going to be a Sigma. It is a different shape but I think it is going to have way better treble extension and an even wider soundstage. I am going to make a model of the housing a put a picture up if anyone would like to see. I also found a website "CNC Machine shop" that makes parts if I draw it out in their CAD program.

 

[John Buchanan]

The 303 and 404 drivers appear to be identical - the differences between the two models lies in the cord between the amp and phones. It would be interesting to see what you come up with design wise.
Treble extension isn't too much of a problem with the Sigma Pro or Sigma/404. The Sigma normal bias had a marked roll off in the treble however.
Currently listening to Derek And The Dominos - Live At The Fillmore via the Sigma/404.

 

[jaycalgary]

My idea turned out to be very impractical when I cut the shapes I needed to see how they would fit together. I am still going to make another one or so but this one is just going to be almost identical to the original. Looks hard to find a Sigma ark Assembly but I do have a couple extra Lamda Sig and pro ones. I think the Lambda ones are about a quarter of an inch longer. The one thing that I want to change is how close the driver is to the ear pads. There is about a quarter of empty space between in the factory pair and I want the driver as close to the earpad as possible.

 

[schorsch]

Hello,
 
I'm very interested in your making efforts.
Sounds intersting to get them made via CNC...
 
Regards Georg
 

 

[scott16]

Would this work well for the acoustic padding?
 
http://www.acousticalsolutions.com/73~ecosorpt-wall-panels?gclid=CMWZhvOoz7YCFYYw4AodtAsAyg

 

[spritzer]

It could work. 

 

[wink]

Quote:scott16

Would this work well for the acoustic padding?
 
http://www.acousticalsolutions.com/73~ecosorpt-wall-panels?gclid=CMWZhvOoz7YCFYYw4AodtAsAyg

http://www.knaufinsulation.com.au/en-au/insulation/earthwool-insulation/rock-mineral-wool.aspx
 
or to be funny,
 
http://www.tradewarehouse.com.au/wire-mesh/galvanised-welded-wire-mesh-chicken-wire-netting/bird-netting-chicken-wire.html