incredible listening experience

[Jim Karr]

I drove to Chicago Saturday to visit a friend I haven't seen in a while. The first thing he insisted was that I listen to his new stereo system.

http://www.focusaudio.ca/index1.htm

These speakers were sitting on some stands in his bedroom, 3 feet by 3 feet out of the corners. Electronics sending the signal was Musical Fidelity integrated amp, no tone controls, couldn't have been class A (running very, very cool).

I own 12 pairs of speakers.....I have never heard a pair of small two-way bookshelf speakers set up a soundstage as realistic as these!

With eyes closed, the walls and room seemed to disappear, and the performers were on stage in front of me.

Kind of a small sweet spot, though....but if they sound that good I'd let someone anchor me to the floor with concrete!

Any ideas on how we can clone these?

[ShinOBIWAN]

Which standmounts are you refering to? The Signature or the Classic?

The signatures use the Scan Revelator tweeters with a modified Eton midbass or so they say.

All look standard fare to me and would be a fairly easy project to clone - you've got the cabinet dimension, drivers and a few of the crossover details. The blanks could be filled in with common sense and modelling.

[ScottG]

If this is the speaker we are talking about:

http://www.focusaudio.ca/graphics/FS...e_original.jpg

the odd thing here is that this midbass driver is clearly showing Eton's "heat-pipe" phase-plug. But their normal 5 inch driver doesn't have this.. so its likely that the driver is custom to focus. Makes me wonder if it has a midrange "bump" for baffle step compensation "contured into" the driver's freq. response. (..or if they are either compensating in the crossover or don't have any compensation.)

either way, even if you could duplicate the crossover you still won't be able to exactly duplicate the speaker because you won't be able to get that specific driver.

this is the driver you can purchase:

http://www.eton-gmbh.de/dlstream.php?FileId=57

[Jim Karr]

Yes, those are in fact the same speakers. The mid/bass driver did have the "pipe" in the center of the dustcap.

How much would the image differ if one was to use the driver without the mod?

[omba]

I am not sure if this is exactly the same driver but

http://www.ritlab.jp/shop/product/speaker/eton.html
http://www.ritlab.jp/shop/product/sp.../5-88825_l.jpg

When you consider shipping cost from Japan, it may well be too expensive though.

Here you find the frequency response of the speaker

http://www.soundstagemagazine.com/me...s/focus_fs688/

[ScottG]

Originally posted by Jim Karr
Yes, those are in fact the same speakers. The mid/bass driver did have the "pipe" in the center of the dustcap.

How much would the image differ if one was to use the driver without the mod?

Long story short: not much.

Long story:

I think that with some effort and without a need for high spl's or high eff.. You could make it better than what focus has done.. even the finish (which is a laquered Mappa Burl veneer).

It's doubtful that this is a first-order design. With that in mind I'd prob. contact member Zaph/John and see what he has to suggest for the normal eton 5 inch and the revelator - both with and without bafflestep compensation. (..and include midbass driver center distance from floor to ***** floor bounce effects.) Heck he might even design the crossover for you if you mail him your drivers to measure (..his tweeter listing doesn't include the revelator).

http://www.zaphaudio.com/

Note that the crossover components will play a BIG part in final sound quality (actually they'll probably sound like cr@p initially, but give'em some burn-in.) I'd suggest copper Goertz inductors and try looking at tonyGee's website for capacitor suggestions. Additionally IF possible do not use resistors in the crossover - rely instead on the resistance provided by the inductors (for a given guage). If that won't provide the resistance your looking for then perhaps wind your own resistors, or get dave at inact audio to make some for you.

http://www.madisound.com/goertz.html

http://www.humblehomemadehifi.com/Cap.html

DIY silver non inductive ww resistors

http://www.intactaudio.com/res.html

I'd also stay away from stuffing and use multiple coats of tempcoat/soundcoat or this same stuff in a latex primer (applied to the midbass frame as well):

http://www.hytechsales.com/insulatin...additives.html

The box (bass reflex) you can model yourself in any number of freeware programs. Remember bracing. Personally I'd use as hard a material as I could cut. Those Ikea wood panels look right for stability, hardness, and cost:

http://www.ikea.com/webapp/wcs/store...ts=15576*16270
also:
http://www.ikea.com/webapp/wcs/store...76&cattype=sub
and:
http://www.ikea.com/webapp/wcs/store...b&pageNumber=2

Decoupling the tweeter (from the cabinet) with microsorb would be an excellent idea. (page 25)

http://www.percyaudio.com/Catalog.pdf

Veneer can be purchased from a number of locations.. I like these people (though they are a bit more expensive than others):

http://www.oakwoodveneer.com/samples/samples4.html

The laqured finish can be bettered with a french polish technique. (though the minwax wipe-on poly would be a lot easier)

http://www.guitarsint.com/map.cfm

[ScottG]

Originally posted by omba
I am not sure if this is exactly the same driver but

http://www.ritlab.jp/shop/product/speaker/eton.html
http://www.ritlab.jp/shop/product/sp.../5-88825_l.jpg

When you consider shipping cost from Japan, it may well be too expensive though.

Here you find the frequency response of the speaker

http://www.soundstagemagazine.com/me...s/focus_fs688/

Certainly looks like the right driver.

Hmm, I'd say there is no baffle step compensation there.

[inertial]

Hi,
perdone me ScottG, I'm not familiar with NRC standard but it seems to me this is 83dB /1 m equivalent ( measured 2mt - plotted 1 mt)
so if I am not wrong , a 4pi str measurement , the response is basically flat so a full baffle step is present. For analogy an LS3/5a is 81,5 dB
, in the same conditions, a SF Minima 82,5 dB,etc. Am I right?
Cheers,
Inertial

[Iron-Wizard]

The tweeters are SC revelators, no wonder you think there great.

[inertial]

IMHO the designer is the responsable of the speaker's performance.
Probably he has spent a lot of hours "voicing" his baby.
Revelator or not,heatpipe or not, always the man make the difference.
Probably Jim Kerr's friend also have spent time to optimize the whole audio chain. And this is foundmental.
I hope you'll can find the original x-over schematic...

Cheers,
Inertial