Good low-cost 12" driver?

[whines]

I have an old 12" Radio-shack dual-voice-coil driver that I picked up when they were getting out of the DIY speaker market, and I've been inspired by this forum to build a box to put it in. If I like the results (and I'm halfway done, good so far!) I plan to replace it with a better driver, although I want to stay on the 'value' side of the fence.

I have a 200w single-channel amp spare (a Marantz 700 which I found at Goodwill, of all places) that I'll use to power it.

The enclosure I'm building is 24x18x16, about 3 cuft3, with an 8" long port with a 3" id. This is based on reccomendations for the Dayton SD315-88, which I'm eying as a replacement.

Any comments on this driver? Would I be a lot better off with a pricer one?

[JCD]

Is the box your building for your current Radio Shack driver designed for that driver or for the Dayton driver?

Box dimensions, port size, port length, etc are driver dependent. IOTW, if a box is perfect for one 12" driver, it PROBABLY won't be good for a different driver. It all depends on the specific Thiele/Small parameters of the driver involved.

As for the Dayton Driver you mention -- I'd say that Dayton is generally regarded as a good value speaker line, but I can't speak for that particular driver.

JCD

[Exocer]

whines, welcome to the shack!

good questions JCD.

Is there any way you can maybe contact radioshack and find the T/S parameters of the driver? We're assuming that it will work adequately in the 3ft^3 box.

[whines]

I built the box thinking of the Dayton driver. I'm just using the Radio Shack one as a stopgap until I'm ready to commit.

Yeah, it would have been smart to plan a bit more firmly! I was just impationt to start and wanted to get some experience before committing to a larger/more expensive project.

The driver I'm using as a temporary stopgap looks like this:

Radio Shack 4-1350 DVC

--------------------------------------------------------------------------------

Nominal Impedance:..........................................4/8 ohm +/- 15%
Frequency Response:...........................................31 Hz-1.5 kHz
Free Air Resonance (Fs) Frequency:....................................31 Hz
Infinite Baffle Resonance Frequency:..................................30 Hz
Piston Area (SD):.................................................0.0527 m2
RMS Thermal Power Limit (PMAX):.......................................120 W
Rated Power Input - Nominal:...........................................60 W
Flux Density (BL):.................................................10.24 TM
DC Voice Coil Resistance (RE, ohms):......................3.6 ohms/7.2 ohms
Voice Coil Inductance (LVC at 1 kHz):..........................0.35/1.43 mH
SPL:...................................................87/89 +/- 2 dB/1W/1m
Moving Mass (Mms):..................................................52.49 g
Electrical Q Factor (QES):........................................1.23/0.60
Mechanical Q Factor (QMS):.............................................4.33
Total Q Factor:...................................................0.53/0.96
Equivalent Acoustic Volume (VAS):...................................269.6 L
Mechanical Suspension Compliance (CMS, UM/N):...................684.24 UM/N
Mechanical Mass of Cone Assembly and Free Air Load:.................52.49 g
Mechanical Mass of Cone Assembly Only:..............................45.54 g
Peak-to-Peak (Maximum) Linear Excursion:............................3.00 mm
Cutout:..............................................11 1/16 Inches/28.2 cm
Depth:.................................................5 1/4 Inches/13.4 cm
Power Handling:................................................60 Watts RMS
Magnet Weight:........................................................18 oz
Speaker Weight:.....................................................60.2 oz

--------------------------------------------------------------------------------


The driver I'm thinking of using is a Dayton SD315-88 12" Shielded DVC Subwoofer:

Specifications: *Power Handling: 120 watts RMS/180 watts max
*VCdia: 2"
*Le: 1.4 mH
*Impedance: 8 ohms per coil
*Re: 3.05 ohms
*Frequency range: 30-1,000 Hz
*Fs: 25 Hz
*SPL: 94.0 dB 2.83V/1m
*Vas: 5.20 cu. ft.
*Qms: 4.00
*Qes: .38
*Qts: .35
*Xmax: 7 mm
*Dimensions: Overall Diameter: 12-3/8", Cutout Diameter: 10-3/4", Mounting Depth: 6".


-----------------

...or perhaps, for a doubling of price, a Dayton QT305-4 12" Quatro:

Specifications: *Power Handling: 250 watts RMS/500 watts max
*VCdia: 2-1/2"
*Le: 2.5 mH
*Znom: 4 ohms
*Re: 3.50 ohms
*Frequency range: 25-200 Hz
*Magnet weight: 56 oz.
*Fs: 27 Hz
*SPL: 93.6 dB 2.83V/1m
*Vas: 4.24 cu. ft.
*Qms: 10.5
*Qes: .37
*Qts: .36
*Xmax: 10 mm
*Dimensions: Overall Diameter: 12", Cutout Diameter: 11", Mounting Depth: 6".

[Exocer]

I dont know that i would bother using the Radioshack driver at all. The Quatro looks like your best bet.

[Mike P.]

I have to agree with Robert. Don't expect too much from the R.S. driver with it's 3mm xmax. It would be fun though to see how little power it will take to bottom it out.

[whines]

The RS driver is only going to be in there until the new driver is shipped, fear not. Although I have tested it and it seems to work better than the smallish pre-built sub that I was already using...at low levels anyways!

I spent a long time plugging values for the different drivers in to WinISD and I eventually settled on the Dayton DVC310-88 driver rather than the Quarto or the cheap shielded one. Both other drivers hit -3db in the mid 50hz range, whereas the DVC looks like it should make it to the mid 20's.

Power handling: 350 watts RMS/per coil, 600 watts total
* Voice coil diameter: 2"
* Voice coil inductance: 1.81 mH
* Nominal impedance: 8 ohm per coil / 4 ohm total
* DC resistance: 2.69 ohms
* Frequency range: 20-450 Hz
* Magnet weight: 112 oz.
* Fs: 21.7 Hz
* SPL: 87.4 dB 1W/1m, 90.4 dB @ 2.83V/1m
* Vas: 4.25 cu. ft.
* Qms: 12.53
* Qes: .38
* Qts: .37
* Xmax: 15.1mm

The 3" port that I was planning to use will probably be a problem, though. Two 3" ports seem to have nearly the same area as a 4" port; if I double up should I do the math as if it was a 4.25" port?

[Mike P.]

WinISD will do the math for you. Just enter the diameter and how many ports you want to use. Your choice of sub has decent specs, especially the 15.1 xmax. Does it model well in your 3 cubic foot box?

[whines]

Well, looks good in WinISD!

[brandonnash]

Out of the shielded dvc and the quattro i'd go with the quattro...BUT if you still want cheap how about This one It's very cheap, models very well in winisd and you could pick up a couple and give you pretty good performance for well under $100.

[Sidi_UC]

http://www.diycable.com/main/product...roducts_id=653

$155 shipped, but perhaps not quite "value". some would consider it to be though.

[Exocer]

Also check out the Dayton DVC 12", currently on sale http://www.parts-express.com/pe/psho...102507-295-185

[whines]

Thanks for the advice! I finally went with the Dayton DVC. The sub is assembled and sounds nice! The only gotcha is some rattling, I suspect from the ports against the brace. (I had to bend the PVC slightly to get them to fit past the brace, and even then it's a close thing)

Next step is to take a look with REW, but that'll have to wait until I'm done moving. At least I have some extra bass ready for the new living room!

[BoomieMCT]

Exocer wrote:

Also check out the Dayton DVC 12", currently on sale http://www.parts-express.com/pe/psho...102507-295-185

**** - beat me to it.

[Exocer]

BoomieMCT wrote:

**** - beat me to it.

No hard feelings

I might pick one up myself.

[tomd51]

Granted I'm a little late to the party as I see the OP has already chosen a specific driver, but for them as well as any others that might be interested, I've got a couple of suggestions.

The first is the Dayton RSS315HF-4 12" Reference HF subwoofer drivers at a little over $100. The second is from Elemental Designs, every now and then they have some of the ED 13Ov.2 subwoofer drivers available as b-stock for the same price as the Daytons above but w/free shipping. Both of these model pretty well in a relatively decent sized enclosure (approx. 3 to 3.5 cu. ft) with a nice combination of extension and SPL.

I recently built a 3.65 cf enclosure tuned to 25Hz for a friend with the 13Ov2 and it does quite well for both movies and music... -TD

[Tiny]

I have just ordered 2 pair of EHQS12 for $25 a speaker. They are going in a sub project.

[evilbeaver]

I've got a practically brand new TC Sound DB500 12" if you're interested.

Ack nevermind I didn't see that you bought your driver already.