DIY drivers and what to look for

[pzaur]

I'm just gathering information and this is inconjunction with my other thread. The whole DIY sub thing is new and I'm learning how to read specs. I'm currently borrowing a DS12 Rythmik and find that it is quite suitable for my room.

DS1200
DS1500
JL Audio 13W1
Dayton Audio 15"

Any particular "ranking" of these based on specs?
I'm in no rush to build right now but need to figure out budget and all.

-pat

 

[gmichael]

I have been eyeing up this TD15S http://aespeakers.com/shop/catalog/product_info.php?cPath=23&products_id=59&osCsid=7677db0c60792fc7ab30062347d47413
And the PR18-1600 passive radiator http://aespeakers.com/shop/catalog/product_info.php?cPath=24&products_id=38&osCsid=7677db0c60792fc7ab30062347d47413

 

[pzaur]

I have been eyeing up this TD15S http://aespeakers.com/shop/catalog/product_info.php?cPath=23&products_id=59&osCsid=7677db0c60792fc7ab30062347d47413
And the PR18-1600 passive radiator http://aespeakers.com/shop/catalog/product_info.php?cPath=24&products_id=38&osCsid=7677db0c60792fc7ab30062347d47413

Those would actually be out of the guesstimated budget. I want to keep the driver under $200 if I can (I'm assuming the DS1500 will probably be more than that...).

-pat

 

[lsiberian]

I'm just gathering information and this is inconjunction with my other thread. The whole DIY sub thing is new and I'm learning how to read specs. I'm currently borrowing a DS12 Rythmik and find that it is quite suitable for my room.

DS1200
DS1500
JL Audio 13W1
Dayton Audio 15"

Any particular "ranking" of these based on specs?
I'm in no rush to build right now but need to figure out budget and all.

-pat

Not sure your current finanicial situation, but my list of subs from cheapest to best(within reasonable cost/size builds.)

Infinity Kappa Perfect 12.1
Infinity Kappa Perfect MidVQ
Exodus Audio Shiva-X
JL Audio 8w7(ultimate music sub IMO)
Audiopulse Axis 12"
Exodus Audio Maelstrom X
Audiopulse Axis 15"

There are certainly other drivers out there, but Kappa's model the best of the low cost drivers

Shiva's are great and you get the great service of Exodus Audio. Given the choice between the 2 I'd opt for the Shiva due to my personal preferences for the company that's working hard to improve their products.

JL Audio 8w7s are among the best subs in the world IMO because they allow small box construction with amazingly high spl and extension for their size.

The Axis 15" is the pinnacle of great subwoofer design IMO. It has very high quality sound while maintaining reasonable cost.

I've modeled lots of drivers and read lots of opinoin. I'd only buy a sub off this list for a build.

Of course if your looking for used driver deals let me know. Maybe I can dig up something sweet.

 

[annunaki]

It all comes down to allotted budget and the goals/expectations of the system.

Linearity of the driver also should be part of the consideration, however one must rely on 3rd party analysis to get that information. Some drivers do not offer it, so one must look for how the driver is constructed, motor design, etc.

 

[pzaur]

I'm actually beginning to believe that I may be able to do an Infinite Baffle in the house. A buddy is pushing for the Dayton Audio driver. Current plan in development is to buy two drivers and then an amp and then build the thing.

This would be a three part process over an extended period because the box couldn't follow until the drivers are selected and amps are expensive.

First thing is to figure out where it would go and I need to do that when the wife isn't around so she doesn't give me all the weird looks...

-pat

 

[WmAx]

Lisberian, I'm surprised... you failed to mention the absolute highest performance subwoofer driver in the world. The AudioPulse LMS Ultra drivers have the most linear motors in the world. If there is something else that matches it, I'm not yet aware. You can get 12" ULTRA LMS from Parts Express. Sound Splinter(they have AudioPulse build their drivers) has a 15" version of the LMS (non-ULTRA version), but the motor on the SS version is not as robust(lower power handling and less excursion) as the ones used on actual ULTRA LMS units so far as I can discern.

OP: Lisberian's list is very accurate. I would also recommend removing the JL W1 or any lesser than W6V2 from the list. The W6v2 is comparable to Kappa Perfect VQ in terms of motor linearity, power handling and excursion. Also, the Rythmik drivers do not provide much output in sealed cabinets; those drivers are far better suited to ported so far as their linear excursion and power handling is concerned. And don't get hyped about 'servo'. A top notch non-servo driver will exceed the performance of a good servo driver in every possible way. The main use of servo technology is to reduce the non-linearity of a driver as it enters it's non linear operating range. Well, top notch non-servo drivers have such an extraordinary linear range that this is not an issue. If you want small size, listen to Lisberian about the JL W7 8" driver. These cost about $250 from discount retailers online, and despite being 8", they will easily produce the SPL and extension of a high quality 12" driver in a rather small cabinet.

-Chris

 

[lsiberian]

Lisberian, I'm surprised... you failed to mention the absolute highest performance subwoofer driver in the world. The AudioPulse LMS Ultra drivers have the most linear motors in the world. If there is something else that matches it, I'm not yet aware. You can get 12" ULTRA LMS from Parts Express. Sound Splinter(they have AudioPulse build their drivers) has a 15" version of the LMS (non-ULTRA version), but the motor on the SS version is not as robust(lower power handling and less excursion) as the ones used on actual ULTRA LMS units so far as I can discern.

OP: Lisberian's list is very accurate. I would also recommend removing the JL W1 or any lesser than W6V2 from the list. The W6v2 is comparable to Kappa Perfect VQ in terms of motor linearity, power handling and excursion. Also, the Rythmik drivers do not provide much output in sealed cabinets; those drivers are far better suited to ported so far as their linear excursion and power handling is concerned. And don't get hyped about 'servo'. A top notch non-servo driver will exceed the performance of a good servo driver in every possible way. The main use of servo technology is to reduce the non-linearity of a driver as it enters it's non linear operating range. Well, top notch non-servo drivers have such an extraordinary linear range that this is not an issue. If you want small size, listen to Lisberian about the JL W7 8" driver. These cost about $250 from discount retailers online, and despite being 8", they will easily produce the SPL and extension of a high quality 12" driver in a rather small cabinet.

-Chris

Of course I can't believe I forgot that one! LMS is just amazing, but you need some space for it.

 

[pzaur]

The Audiopulse drivers are way over the budget, unfortunately.
I'll do some searching for the W8. Any suggestions for online retailers?

-pat

 

[lsiberian]

The Audiopulse drivers are way over the budget, unfortunately.
I'll do some searching for the W8. Any suggestions for online retailers?

-pat

http://www.sonicelectronix.com/item_4198_JL+Audio+8W7-3.html?utm_source=froogle&utm_medium=organic&utm_campaign=froogle

 

[lsiberian]

http://cgi.ebay.com/Infinity-Kappa-Perfect-12-1-1400watt-12-4ohm-subwoofer_W0QQitemZ320394086207QQcmdZViewItemQQptZCar_Subwoofers_Enclosures?hash=item4a98f9c73f&_trksid=p3286.c0.m14&_trkparms=65:12|66:2|39:1|72:1205|293:1|294:50

This is a really good deal.

 

[WmAx]

I've used Sonic Electronix before; it's a pretty good company. Just be sure to call in and make them PHYSICALLY VERIFY they have the item(s) in stock before you order because they have problems keeping the 'online' inventory numbers in check, in my past experience.

If you are interested in modeling the W7 8", I can provide usable T&S parameters for complete/accurate modeling to you. I have measured two batches from two different sources of 8W7 drivers, and the VAS in reality varies quite a bit from the factory provided specification, as well the factory does not provide complete specs to model the driver properly.

The 8W7 has a motor that would be sufficiently powerful to drive a really good 15" driver! It also has almost no compression. 3rd party tests show extended 500 watt input to result in only 1dB of compression. Unlike most drivers, this one can be modelled and you can actually believe the high power modeling results.

Picture of one of the 8" W7 units I measured, from the rear....

-Chris

 

[WmAx]

http://cgi.ebay.com/Infinity-Kappa-Perfect-12-1-1400watt-12-4ohm-subwoofer_W0QQitemZ320394086207QQcmdZViewItemQQptZCar_Subwoofers_Enclosures?hash=item4a98f9c73f&_trksid=p3286.c0.m14&_trkparms=65:12|66:2|39:1|72:1205|293:1|294:50

This is a really good deal.

Good deal? In the low res pic, I can see incredible abuse; the cone is dented and dis-formed substantially. I bet in real life, it looks much worse!

-Chris

 

[pzaur]

-Chris

Does this constitute subwoofer porn?! I mean...damn...that thing is huge!

-pat

 

[lsiberian]

Good deal? In the low res pic, I can see incredible abuse; the cone is dented and dis-formed substantially. I bet in real life, it looks much worse!

-Chris

guess I whould have looked at the pic. I've never seen a driver with that much damage on Ebay before. That's terrible.

Don't buy that driver.

I like a narrow ported box for the 8w7. This takes adavantage of it's small size while giving you very nice performance.

(I'm using your TS parameter I believe)

I really like the look of a 30hz tune in a 1 cuft box. Especially if music is the primary purpose of the driver.

The biggest issue seems to be the port air velocity. Not sure how you might deal with that Chris.

 

[tcarcio]

I have the Shiva and it is a fantastic driver. It was mentioned already but here is the link....http://www.diycable.com/main/product_info.php?products_id=653

 

[WmAx]

guess I whould have looked at the pic. I've never seen a driver with that much damage on Ebay before. That's terrible.

Don't buy that driver.

I like a narrow ported box for the 8w7. This takes adavantage of it's small size while giving you very nice performance.

(I'm using your TS parameter I believe)

I really like the look of a 30hz tune in a 1 cuft box. Especially if music is the primary purpose of the driver.

The biggest issue seems to be the port air velocity. Not sure how you might deal with that Chris.

You can keep the port velocity reasonable using a 58" long 3.5" x 6' port. You will have to build this horizontally folded on the back wall, and it will be a rather complex build. The end size of the outer cabinet will be something like 1.8-2 cubic feet in the end, which is about the external size of the F110. A 15" cube for example, would be big enough. It gets easier if you want to to the narrow and long or tall cabinet, as then the port only needs simple standard folding design to fit in the cabinet. If you would go to 2.5 feet total external size, you could get F3 around 20Hz. It would be amazing to say the least, to realize the performance from such a small package. It will easily outperform the F110 since you are allowing a vent to re-enforce the lowest octave on the 8W7. For just music, a sealed 1 cubic foot cabinet is sufficient. You can get very high SPL output down to about 37Hz. Just use a tiny bit of EQ to boost a couple of DB to get flat response to 37Hz. You can do flat to 30Hz sealed as well; but you will limit the highest dynamic output a bit. Remember, these are not normal 8" subwoofer drivers; they product the real-world output of a high quality conventional 12" subwoofer driver.

-Chris

 

[Matt34]

You can keep the port velocity reasonable using a 58" long 3.5" x 6' port. You will have to build this horizontally folded on the back wall, and it will be a rather complex build. The end size of the outer cabinet will be something like 1.8-2 cubic feet in the end, which is about the external size of the F110. A 15" cube for example, would be big enough. It gets easier if you want to to the narrow and long or tall cabinet, as then the port only needs simple standard folding design to fit in the cabinet. If you would go to 2.5 feet total external size, you could get F3 around 20Hz. It would be amazing to say the least, to realize the performance from such a small package. It will easily outperform the F110 since you are allowing a vent to re-enforce the lowest octave on the 8W7.

-Chris

Would the O-Audio amp be sufficient to power this?

 

[WmAx]

Would the O-Audio amp be sufficient to power this?

The O Audio 500W should be. The 8W7 should be fed 400 RMS, at least(more power is better, of coure). In addition, the O Audio 500W has a subsonic filter to protect against excursion under the tuning frequency.

It would be incredible to have like 4 x 15" cubed little boxes, each with a powered JL8W7 placed around the room.

-Chris