Jim Griffin's JX92S designs

[Jim Griffin]

Jon,

I replied to your e-mail a couple of days ago but perhaps you did not receive my reply.

At any rate the crossover is the same for the mini-monitor as for the ML-TL version with the assumption that the baffle width is the same for each design. In case you don't have a copy of the crossover diagram, it is posted in Post #9 of this thread:

JX92S/G2si Crossover Diagram

Let me hear if you need more aid.

Jim

[tomtom]

Originally posted by Jim Griffin
Navin,

You can e-mail me for more info.

Thanks,

Jim

Hi all

Firstly sorry for my bad english.

Im Tomas 31 y.old from Slovakia - middle Europe- very new here - and very new in "higher"end.
Im looking about very good stereo /expandable to surround later/ to our appartment. After looong initial research I decide to go DYI. Fullrange speakers with Jordan drivers - most probably - 92s maybe r6hd /less probably/. Amp will be some T-amp modification. Signal source will be some pc sound card or external dac later. The attached picture is "fake" visualization my room with jims minimonitor / sorry for that name but i dont know better for them/.
This speakers position is unfortunately almost only possible - So wall mount and left speaker almost in corner. Doublechair will be turned to "listening and watching position" as there is projector screen between pc monitor and right speaker.

I want use this enclosures - but link for original plans dont work.
I also thinks that i must vent enclosure in front or in bottom or not at all /because wall/.

I apreciate any comment to eclosure choice, drivers choice, and about t-amp suitability to 92s. I want just moderate loudness.

I also apreciate original plans very much

Thank you very very much

/everybody must start sometime /

[albertshi]

Hi, Jim,

I had bought a speaker by JX92S and was told the speaker was built per your plan. I like this speaker very much! It is very good for most of music I like, Jazz, human voice, and piano..., but recently I wanna if I can make it better with an additional subwofer using like SEAS H1209 L26RFX/P? because I want the speaker a little better for symphony if it is possible. Any suggestion for that?

Thanks a lot!
Albert

[Jim Griffin]

albertshi,

I am assuming that you have my mini-monitor design with the JX92S in a 0.5 cu. ft. box. With a ported box this design goes to 55-60 Hz as the 3 dB rolloff point.

You have several possibilities to consider. The easy way to add a sub would be to retain your current speakers and then build the sub to blend with them. I haven't used the Seas L26 but it widely used in 3-way speakers and would be able to blend in with the Jordan drivers just fine. I would stuff a sock or a piece of acoustic foam into the port tube and crossover in the 80-90 Hz range. Thus the minimonitors would be acting as a sealed box which would relieve their low end cone movement versus the ported box.

If you are willing to consider a non-sub solution, take a look at using your JX92S drivers in a new enclosure. My Jordan with a ribbon MLTL design does the trick in this case. It is more full range--goes below 40 Hz on the low end and extends better on the upper end because of the ribbon tweeter. Likely, it would suit your type of music just fine.

There is a thread that talks to this design at:

Jordan with a Ribbon MLTL

This design is the best JX92S version that I have built and I highly recommend it. The boxes are easy to build and the ribbon tweeters are currently on sale for 30% off at Parts Express.

If you need help with the Jordan with ribbon MLTL design, please contact me.

Jim

[castlesteve]

Who is selling Jordan drivers in the USA now? The MLTL design is looking awfully tempting.
Steve.

[Godzilla]

Has anyone built this?

http://www.zillaspeak.com/BIB-Jordan.asp

[ttan98]

Jim,

You have use Aurum Cantus 2Si successfully with Jordan, x-over at 3kz(I think).

Do you think this tweeter can be recommended for most 2 way speakers, eg with scanspeak woofer 8545?

If so what do I have to look for when designing the x-over?

eg. x-over freq., use 4th x-over, phase change, correction circuit, etc.

Does the tweeter get damaged easily, eg shorter, burnt?

Some designers ask me to steer clear of ribbon. What do you think?

thanks

[Jim Griffin]

Where to buy Jordan drivers?

The North American distributor of Jordan drivers at this point is Mark Audio which is located in Hong Kong. They air ship so you can get what you want relatively soon after you order. Now the prices aren't cheap but we are talking drivers comparable to the better European built speakers. Mark Audio is at:

www.markaudio.com

Use of ribbon tweeters in this design?

I use ribbons in several designs and suggest care in crossover values. What works best for the Aurum Cantus G2si is a 3rd or 4th order at 2500 Hz or greater. Plus since the tweeter is more sensitivity than the woofer in the Jordan with a ribbon design, you pad the tweeter down to match with the Jordan so you have additional protection for the G2si.

I have never destroyed a ribbon but I take care in the design and use of them. For example, you should prevent turn-on transients, watch volume levels, and such in addition to the design care. The ribbons in the Aurum Cantus drivers can be replaced by the user if they sag or fail but so far I haven't had to attempt replacement.

[castlesteve]

Thanks Jim. I`d better start saving my pennies. Those are expensive 4" drivers. Steve.

[navin]

Originally posted by castlesteve
Thanks Jim. I`d better start saving my pennies. Those are expensive 4" drivers. Steve.

The G2Si are not exactly cheap either! :-)

BTW JIm, just a question...

Since the JX92 is capable upto about 5K or 6K (some say even 10K) why XO it at 3K. Why not use a tweeter that is bandwidth limted to above 5K and let the JX92 funtion as a widerange instead of a good midbass (there are a few 5" midbass that can operate upto 3K)?