Kappa Perfect VQ 12 or...

[fredk]

I want a sub that will do a good job on pipe organ music reaching down below 20Hz (OK, maybe also to deliver reasonable rumble for movies). I am guessing that I should aim for something that plays flat to somewhere around 15Hz??

I generally listen to music at between 70 and 85db and to movies at around 70-75db: not so loud.

I see that the Kappa perfect is very highly regarded here, but is only written about in terms of 20Hz and above performance. Can I get reasonable bass below 20Hz with this driver?

Since I have budget constraints, the alternative would be a larger, and I am assuming, less linear driver. Is a driver like the 18" Mach 5 ixl going to perform reasonably when not driven hard?

 

[Guiria]

If you're rarely going to crank it I would look into the rythmik audio servo subs. The servo technology allows them to play pretty low (into the teens). Some users have them here and there are some pretty good things about them over at hometheatershack as well.

From what I've read they do not have huge output capabilities and the distortion climbs pretty fast when driven hard. At lower levels however I think the sub would perform pretty well.

Disclaimer - I have never heard this line of subs, although they will be in the running when I actually get around to purchasing a new subwoofer.

 

[WmAx]

I want a sub that will do a good job on pipe organ music reaching down below 20Hz (OK, maybe also to deliver reasonable rumble for movies). I am guessing that I should aim for something that plays flat to somewhere around 15Hz??

I generally listen to music at between 70 and 85db and to movies at around 70-75db: not so loud.

I see that the Kappa perfect is very highly regarded here, but is only written about in terms of 20Hz and above performance. Can I get reasonable bass below 20Hz with this driver?

Since I have budget constraints, the alternative would be a larger, and I am assuming, less linear driver. Is a driver like the 18" Mach 5 ixl going to perform reasonably when not driven hard?

The problem using the Perfect VQ is related to excursion. When you tune the vent that low, the range just above vent tuning starts to require massive excursion capabilities at higher SPL ranges.

A suitable driver for your use would be the JL Audio 12W7 in a large(around 6-7 cubic feet) slot ported cabinet system. It has sufficient excursion to be used to these extreme low tuning points. You could easily get high output down to 13-15Hz range. I recommend the W7 because it has the linearity of the Kappa Perfect, but with substantially increased excursion(2x) and power handling.

-Chris

 

[fredk]

... JL Audio 12W7...

I have budget constraints

One of these things,
is not like the other...

I understand that the 12W7 is an exellent driver, but its a little out of my range.

So, the short answer is that the Kappa perfect isn't going to go that low because it dosn't have enough excursion. Thanks

So, if I want to go that low and don't have the funds for the 12w7, I need to compromise with a larger, lesser driver.

Guiria, I'll look into the rythmik audio servos.

Thanks for your help gents.

 

[WmAx]

One of these things,
is not like the other...

I understand that the 12W7 is an exellent driver, but its a little out of my range.

So, the short answer is that the Kappa perfect isn't going to go that low because it dosn't have enough excursion. Thanks

So, if I want to go that low and don't have the funds for the 12w7, I need to compromise with a larger, lesser driver.

Guiria, I'll look into the rythmik audio servos.

Thanks for your help gents.

The Servo is not going to add any LF ability. The purpose of a SERVO is help correct non linear motor behavior

You CAN use the Kappa Perfect VQ tuned as low as you specified. It just would not have the high output capability that it normally has. You would be sacrificing maximum output to extend the bandwidth. It would still outperform many commercial 12" subwoofers even with the compromised output. Realize, with the optimum cabinet, it can produce nearly 120dB in an average sized room, given sufficient amplifier power and optimal placement. You will lose probably lose a minimum of 6dB of overall output by tuning the system to work down to 14Hz. Also, the cabinet will end up around 6-7 net cubic feet.

I can suggest other drivers, but the problem is, they are not verified to be as linear as the drivers I normally recommend. I presume you desire maximum SQ for music purposes. If you would be happy with 6db reduced overall output with the Kappa Perfect, I will run some numbers to give you specific cabinet and port specifications required, as well as other construction details that must be addressed.

-Chris

 

[fredk]

After your last response, I thought I was out of luck with the Kappa 12.

If I listen to music at 85db, would 20db headroom for peaks (105db) be reasonable? That is 15db down from from 120db max.

By the way, I picked ~15Hz because, from what I understand, the 16Hz key is usually the lowest on an organ.

Thanks for the offer to model for me. I am still at the very preliminary stage on this one and a build, even based on this modestly priced driver is very much dependant on how many extra days off my employer is going to give me this year (automotive ). My bonus this year was an extra 9 days off at Christmas.

I may also end up experimenting with a larger lower cost driver if I find a good deal used. I would probably give up on another sub if I wasn't so obsessed.

 

[WmAx]

After your last response, I thought I was out of luck with the Kappa 12.

If I listen to music at 85db, would 20db headroom for peaks (105db) be reasonable? That is 15db down from from 120db max.

By the way, I picked ~15Hz because, from what I understand, the 16Hz key is usually the lowest on an organ.

Thanks for the offer to model for me. I am still at the very preliminary stage on this one and a build, even based on this modestly priced driver is very much dependant on how many extra days off my employer is going to give me this year (automotive ). My bonus this year was an extra 9 days off at Christmas.

I may also end up experimenting with a larger lower cost driver if I find a good deal used. I would probably give up on another sub if I wasn't so obsessed.

I just made a post regarding another driver, a 15" Dayton RS, at the other forum. If you are willing to go with a rather huge ported enclosure (10-11 feet internal, net, not including the slot port), that driver could do what you need, even though it's linearity is not known by me.

As for the Kappa, it could deliver safely, 110db or so, in room from 14Hz on up, assuming you have an average sized room(2000 cubic feet) and you corner load the subwoofer. But you must be careful not do drive the unit past this SPL range, or it may be damaged.

-Chris

-Chris

 

[Sheep]

I just made a post regarding another driver, a 15" Dayton RS, at the other forum. If you are willing to go with a rather huge ported enclosure (10-11 feet internal, net, not including the slot port), that driver could do what you need, even though it's linearity is not known by me.

As for the Kappa, it could deliver safely, 110db or so, in room from 14Hz on up, assuming you have an average sized room(2000 cubic feet) and you corner load the subwoofer. But you must be careful not do drive the unit past this SPL range, or it may be damaged.

-Chris

-Chris

You said your name twice...

SheepStar

 

[fredk]

Thanks Chris. I need to go back and do some measuring to verify what levels I am lisening at. I did a quick measure last night and it looks like my movie watching is done at more like 75-80db.

I would expect that if I went with the kappa, it would be prudent to employ some sort of filter to keep the driver from bottoming out.

I responded on alternative drivers in the other thread. Given the responses, its probably best to continue the Kappa conversation here.

 

[WmAx]

Thanks Chris. I need to go back and do some measuring to verify what levels I am lisening at. I did a quick measure last night and it looks like my movie watching is done at more like 75-80db.

I would expect that if I went with the kappa, it would be prudent to employ some sort of filter to keep the driver from bottoming out.

I responded on alternative drivers in the other thread. Given the responses, its probably best to continue the Kappa conversation here.

The only effective protection filter would be a dynamic EQ system as found in the Behringer DCX2496. But this would be a substantial added cost to the system, although, the DCX will allow all sort of ideal performance characteristics from your system.

-Chris

 

[annunaki]

Though extremely large, the Maelstrom-X would be a decent option at hitting the lowest of octaves. It is a very linear design and would be capable of easily hitting 114db+ in room at 14hz if not substantially more.

The enclosure size is 17 ft^3 tuned to 14hz with a 4" x 18" vent 49-7/8" long. The-3db point (F3) from reference is at an impressive 15hz! LINK Warpdrv knows of a way to get them cheaper too, PM him.

If one can deal with the size, approximately 19.5" x 25.5" x 75.5", it would probably as realistic as possible at creating pipe organ notes. Be careful with your window seals though.

What is nice about this option is the headroom capacity is phenomenal. During normal listen sessions (80db-90db) this thing would be pressurizing the entire room. If you wanted to turn it up, it may make you vomit.

 

[TLS Guy]

I want a sub that will do a good job on pipe organ music reaching down below 20Hz (OK, maybe also to deliver reasonable rumble for movies). I am guessing that I should aim for something that plays flat to somewhere around 15Hz??

I generally listen to music at between 70 and 85db and to movies at around 70-75db: not so loud.

I see that the Kappa perfect is very highly regarded here, but is only written about in terms of 20Hz and above performance. Can I get reasonable bass below 20Hz with this driver?

Since I have budget constraints, the alternative would be a larger, and I am assuming, less linear driver. Is a driver like the 18" Mach 5 ixl going to perform reasonably when not driven hard?

I think you are obsessing too much. Only the largest organs have 32 ft stops (17Hz). Even then few scores call for the 32 ft stop. Most of the bass from the pipe organ comes from the 16 ft principals (34Hz).

I'm a great lover of the pipe organ, and the rig in my signature with Fs in the mid twenties, although measuring in room flat to just about 20 Hz, reproduces the pipe organ with great realism, including ones I know well.

 

[WmAx]

Though extremely large, the Maelstrom-X would be a decent option at hitting the lowest of octaves. It is a very linear design and would be capable of easily hitting 114db+ in room at 14hz if not substantially more.

The enclosure size is 17 ft^3 tuned to 14hz with a 4" x 18" vent 49-7/8" long. The-3db point (F3) from reference is at an impressive 15hz! LINK Warpdrv knows of a way to get them cheaper too, PM him.

If one can deal with the size, approximately 19.5" x 25.5" x 75.5", it would probably as realistic as possible at creating pipe organ notes. Be careful with your window seals though.

What is nice about this option is the headroom capacity is phenomenal. During normal listen sessions (80db-90db) this thing would be pressurizing the entire room. If you wanted to turn it up, it may make you vomit.

The Dayton RS 15" should do about the same SPL at 14hz in room, but with a substantially smaller cabinet(about 11 cubic feet, slot ported). Just a heads up. This of course assumes the Dayton is free of any significant power compression and has a completely linear motor/suspension in it's published xmax range.

-Chris

 

[fredk]

The enclosure size is 17 ft^3

I don't mind big, but I do still need some room to actually move about!

of easily hitting 114db+ in room at 14hz

I feel like that guy in Monty Python's The Holy Grail. "But I don't want to hitt 114db+ at 14hz, I just want to sing... er listen to pipe organ music." Please don't make me fire arrows.

I think you are obsessing too much. Only the largest organs have 32 ft stops (17Hz). Even then few scores call for the 32 ft stop. Most of the bass from the pipe organ comes from the 16 ft principals (34Hz).

Thank you for that info TLS GUY. I had been wondering if I was accurate, but didn't think to contact you directly. For some reason, I had it in mind that the lowest stop on most organs was 16Hz., but I was wondering how often it gets used.

So the Kappa perfect would do just fine for pipe organ music and would give a good boost to my HT over my current sub (-3db point is 28Hz).

It would also be a lot easier to fit into my rather cramped room.

Hmm...

 

[annunaki]

The Dayton RS 15" should do about the same SPL at 14hz in room, but with a substantially smaller cabinet(about 11 cubic feet, slot ported). Just a heads up. This of course assumes the Dayton is free of any significant power compression and has a completely linear motor/suspension in it's published xmax range.

-Chris

Chris,

114db was the anechoic number given by WinIsd with 1000 watts rms, I used it as a safety point. The Maelstrom is a highly linear device utilizing XBL2 technology in the motor. XBL2 equipped drivers are known for linearity over the usable/published xmax as well as having very smooth inductance curves for reduced power compression.

It would not surprise me if it could hit in excess of 120db depending upon the amount of room gain at said frequency. With more power higher numbers would be attainable.

I do agree, the cabinet is extremely large. They do make some passive radiators for said driver. I can model that up as well. Even if it does not fit the OP's budget, it would be nice to know...

 

[annunaki]

I don't mind big, but I do still need some room to actually move about!


I feel like that guy in Monty Python's The Holy Grail. "But I don't want to hitt 114db+ at 14hz, I just want to sing... er listen to pipe organ music." Please don't make me fire arrows.


Thank you for that info TLS GUY. I had been wondering if I was accurate, but didn't think to contact you directly. For some reason, I had it in mind that the lowest stop on most organs was 16Hz., but I was wondering how often it gets used.

So the Kappa perfect would do just fine for pipe organ music and would give a good boost to my HT over my current sub (-3db point is 28Hz).

It would also be a lot easier to fit into my rather cramped room.

Hmm...

If that is an acceptable tradeoff, the Kappa or W6v2 will suit your needs quite easily.

 

[fredk]

Doing some searching on the Kappa Perfect 12 to find the best source, I find that it is now a discontinued driver? It seems my only option on this driver is to buy in the US (usually involving high shipping costs and wacky exchange rates).

My other option is to see if something comes up used.

XBL2 equipped drivers are known for linearity over the usable/published xmax

Interesting. At $365US, the Maelstrom X is out of my range (and probably overkill for my situation), but the CSS SDX15 at $250CDN is very close in price to what I would have to pay for the Kappa Perfect 12.

... and for something completely out of left field, someone local is selling an Ascendant Audio Avalanche 12 for not much. Its also an XBL2 design and from a quick search the 15/18" were very highly regarded, but I can't find anything on the 12. At the price, it might be a nice driver to experiment with for a first built.

 

[WmAx]

... and for something completely out of left field, someone local is selling an Ascendant Audio Avalanche 12 for not much. Its also an XBL2 design and from a quick search the 15/18" were very highly regarded, but I can't find anything on the 12. At the price, it might be a nice driver to experiment with for a first built.

Key here is 'experiment'. Where as the drivers suggested to you here were proven to be exceptional in high end designs/applications. The JL Audio W6v2 that annukai mentioned, btw, is every bit the equal of the Kappa Perfect VQ 12.

-Chris

 

[fredk]

Just throwing it out there. You never know...

 

[annunaki]

Warpdrv knows of a way to get something like $90.00 off the Maelstrom-X. Not sure if that helps or not.

The Infinity Kappa Perfect 12 VQ is not a discontinued driver.