Ahuja SK12-FRX

[drgb]

I bought a pair of these drivers yesterday and had them playing for hours. I am really delighted to report that these are indeed a very nice pair of speakers for the price (which is about 2.8k rupees for a pair btw).

I am starting this thread for fellow FMs to put forward their experience with these drivers and the designs they used with it. Will help prospective diy'rs to get the ball rolling and avoid mistakes other FMs have made in the past.

I am Sorry if this topic has been covered in some other thread, i could myself only find bits and pieces of details here and there. I do believe that this driver deserves a thread of its own.

 

[ratheesh]

So you built a cabinet around it?

 

[Sumanta]

They indeed are worth a separate thread.
Some of us have built Open baffle speakers. You can search posts of mine and Jaudere. You can also refer to blog of mine for your reference.

 

[drgb]

Aside from open baffles, what designs can this driver be used for? Anyone experimented with anything else??

 

[drgb]

So you built a cabinet around it?

No im working on it. Most forum members have suggested using an open baffle. The only caveat is that to get a good low end one needs to mount this on a relatively large baffle. Same goes for ported and sealed enclosures.

 

[spirovious]

Ahuja suggests sealed box.They have given dimensions too in their pdf.

 

[drgb]

They have. Infact ahuja sells a premade box for this speaker with the same dimensions for around 7k (includes the driver). I didnt test it but given the T/S parameters for this driver, that size given in the pdf looks dubious. Maybe their specifics will work well outdoors (afterall thats what they were made for).

 

[Ravindra Desai]

No im working on it. Most forum members have suggested using an open baffle. The only caveat is that to get a good low end one needs to mount this on a relatively large baffle. Same goes for ported and sealed enclosures.

For indoors and for full-range HiFi response, go for the bass reflex enclosure that I mentioned in the other thread here.
I have built a few pairs and can vouch for it. I can assure you that you will then NOT need a separate subwoofer.
It will be audiophile stereo at its best!

Keep us posted on your progress.
Thanks!!

Regards,

Ravindra.

 

[VSTEREO]

I have recently joined Ahuja FRX-12" league. Currently drivers are in break-in period (played 40 hrs. already).

Pros:

• As expected in any FR, Mid range is clean
• Top end sparkle is good so helper tweeter may not be needed
• Cost. Landing costs for a simple 4" (Dayton or other brands) crosses 5K here in India so 3.5k for a pair is very reasonable price considering its quality

Cons:

• Sweet spot is narrow. I have 4" Dayton FR and 8" FR which I regularly use in my stereo setup and compared to these, 12" has narrow sweet spot
• Asks for big enclosure to extract more bass from the drivers. So definitely not suitable for small listening areas
• Asks for more break in period. I would expect minimum of 50-100 hrs. of playing for drivers to deliver its full potential

Whoever wanted to spend little money and have nice tube setup (pre or buffer or power) should try this out.

 

[Sumanta]

Aside from open baffles, what designs can this driver be used for? Anyone experimented with anything else??

One can make an omni directional speaker set with a MLTL tapered design back. IMO, that will be the least wide speaker set. I think I can manage the width within 320mm on top, much less at bottom. Well, but the baseplate will again need to be 300mm or so. So, safely one can assume a 12" wide speaker cabinet.
I can design one sketch to post here, Hari or someone else can simulate it.
It will be an open design for anybody to use and report here the result.

 

[Naveenbnc]

One can make an omni directional speaker set with a MLTL tapered design back. IMO, that will be the least wide speaker set. I think I can manage the width within 320mm on top, much less at bottom. Well, but the baseplate will again need to be 300mm or so. So, safely one can assume a 12" wide speaker cabinet.
I can design one sketch to post here, Hari or someone else can simulate it.
It will be an open design for anybody to use and report here the result.

That would be really fun to learn...
Just a rough sketch on a paper will do ....

 

[drgb]

Reviving this thread after a long time.
I'm back in India for some R&R.
My nephew has been using this driver in open baffles and he seems to be enjoying them quite a bit. I listened to his implementation with a baffle correction circuit and i must say that i was impressed at the overall tonality. However the low end was just not "there" for me. Dont get me wrong, it sounds fantastic but still could use some work.
Which brings us back to the question of closed baffles.
I know that many members have opined to use a helper woofer to bring in the low end kick but the added amplification and crossover requirements make it a not so "purist" appraoch for this humble driver.
Cutting to the chase, we tried to simulate the drivers for a bass reflex enclosure as suggested by @ravindra sir, it seems good but the design itself is very difficult to cut and assemble. Lot of wood wasted and the cost of cabinets shot upto celestial levels. (My nephew also simulated these for some vintage jensen drivers and they were fabulous on paper).
At this point, is there any other design suggestion for this driver? Perhaps a BL Horn or a transmission line.
Any help from ya peeps will be appreciated!
Regards,
Drgb

 

[drgb]

Add active bass on OB, 15" driver, crossed around 120-140hz. Simple and inexpensive. Use a subwoofer amp with speaker level inputs. You may want to try a single H frame also.

BTW BSC does not work in dipole.

Yes we are actually trying to avoid any extra electronics at this stage. Besides since the driver can technically reproduce upto 50Hz, I'm sure there must be some design that can give us a near fullrange performance without the help of extra drivers or electronics.

 

[frend2001]

I would love to see a TL implementation for this driver. I agree with OP that adding further electronics wouldn't be a purist approach.

TL lords, chime in please.

 

[Hari Iyer]

You can try TL simulation with LA or HornResp application to determine applicability before actually building with published parameters

 

[Thirumalkumaran]

Go 2 of them just to "try"! Running them through winisd and testing it without baffle confirms what's been discussed here..
This needs a large box to get it's full potential
Mids and highs are it's strengths.
My way of approaching this is to create a sealed enclosure tuned to about 80Hz or might be higher, and addin a 12 sub to "patch" the low end. This might yield me a box which is 48HX13.5WX12D..