Hi-Vi S1 Coaxial mid/tweet tested

[jkrutke]

Hi all,

I just finished up testing this driver. Results and comments are in my blog. Quick links to the data are below:

Image - Hi-Vi S1 tweeter frequency response
Image - Hi-Vi S1 tweeter harmonic distorion
Image - Hi-Vi S1 tweeter cumulative spectrum decay
Image - Hi-Vi S1 tweeter impedance close-up
Image - Hi-Vi S1 tweeter off axis response, 15 and 30 deg

Image - Hi-Vi S1 mid frequency response
Image - Hi-Vi S1 mid harmonic distorion
Image - Hi-Vi S1 mid cumulative spectrum decay
Image - Hi-Vi S1 mid impedance close-up
Image - Hi-Vi S1 mid off axis response, 15 and 30 deg

Image - Hi-Vi S1 mid and tweeter 2 sample frequency response

It's definitely an oddball. Now all we need is someone to rip a pair apart and see if we can fit a vifa D26NC55 in there or maybe a Seas neo dome. I'll have to avoid the temptations to do that myself, since I don't own the test units.

[Dylan Matlow]

It's definitely an oddball. Now all we need is someone to rip a pair apart and see if we can fit a vifa D26NC55 in there or maybe a Seas neo dome. I'll have to avoid the temptations to do that myself, since I don't own the test units.

My thoughts exactly. It would be interesting to see exactly how much impact that midrange profile has on the frequency response of the tweeter as well.

[jdybnis]

Triaxials next?

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=297-462

[cotdt]

It would work great in an MT or MTM, where you can put the woofers close. it seems like you can cross at 5-6kHz and use a notch to smooth the tweeter's response.

[Mark K]

John,

Can't you just send them back to the owner via dlr. He seems to be pretty good at opening up and modding-the mid doesn't look that bad. Stick a nice tweeter in there and voila!

[AJINFLA]

I'm great at opening stuff up too. It's the putting it all back together that always seems to get me.
Thanks for the test John. Disappointing design, but maybe the whole "Midrange/Tweeter Unit" concept won't be such an abstract idea anymore.
I hope.

cheers,

AJ

[jkrutke]

John,

Can't you just send them back to the owner via dlr. He seems to be pretty good at opening up and modding-the mid doesn't look that bad. Stick a nice tweeter in there and voila!

Hi Mark,

It's good to see you taking a break from teaching linear distortion over on DIYaudio. I personally didn't want to get involved because it's rather difficult to teach someone who doesn't want to learn. I admire your patience.

I'm sure DLR is waiting with a screwdriver and a grin for anything we can send him. Poking and prodding around this S1 driver, it looks like a screwdriver isn't going to help much... lots of adhesive holding this thing together, and no screws anywhere to be seen. Modding looks a bit destructive at best for this one.

Triaxials next?

Hmmm, I don't see a lot of value in the triaxial version when the S1 and a D6.8 would fit in a similar size box, have deeper bass, more output, sound better, etc...

The S1 is a unique concept, but I can't say if I'd rather use that instead of a RS52 with a cheap neo tweeter. What is the value of better vertical lobing between the mid and the tweeter?

[jdybnis]

I was thinking more of a MXM, with the M being D6.8 and the X being the triaxial.

It seems like a fun challenge, more than a good practical design. Price/performance wise I'm sure it wouldn't match up to the RS52 and cheap neo tweeter. But it is not the typical design. Anyways, I've added it to my (long) list of things to play with.