Small Sealed Sonosub

[wrenchddm]

I saw these speakers in good low-cost 12". would they work in a 14"x26" sonasub.wanted to make it a sealed dual speaker.can't find info on a sealed tube.one other question.can you tell the ohm of a speaker without any markings on it.this is the speaker http://www.edesignaudio.com/edv2/pro...roducts_id=183

[Sonnie]

Here are the specs:

Power Handing : 200w
Avaliable Voice Cois : Single 2 & Single 4
Sealed Box Size : 1.5cF
Vented Box Size : 2.0-2.5cF
Qts: .375
Qes: .49
Qms: 1.506
Fs: 25.5 Hz
Re: 1.8
Vas: 157 L
Mms: 90 g
Bl: 7.2 T*m
SPL: 89.1 dB
Sd: 510 cm^2
Xmax: 9.1 mm
Voice Coil : 50 mm

It's available in 2 ohm or 4 ohm as stated above.

Personally I would stick with the more proven drivers from SoundSplinter and Fi Audio and a few others. Even the Dayton's from Parts Express have better specs than this one does.

[Mike P.]

They're ok if $50 is your budget and your expectations aren't too high. But as Sonnie stated, there are better choices.

[wrenchddm]

I would like to spend less than $100.00 per speaker.Have any better choices?

[brent_s]

For $25, each those eD EHSQ12's are hard to beat. If 14"x26" is your internal air space, that's a pretty decent match for a single driver in a sealed alignment. You won't set the world on fire, but a pair would give you 99db @ 1m @ 20hz groundplane...maybe 6 to 12 dB more corner loaded in room. If could boost your volume to the 4 ft^3 range to go ported, a single EHQS12 can deliver 101db @ 20hz groundplane from only 100 watts.

I've actually got a couple of what I think are better options, but I'm in a bit of a time crunch right now and don't have time to get all of the links pulled together. Check back later this weekend. In the meantime, download a copy of WinISD Pro and read the tutorials in the help files and then start doing a bit of modelling to get a feel for what various tradeoffs in size/power/tuning/etc. do.

-Brent

[wrenchddm]

thanks i will try winISD this weekend.i wanted 2 in one tube.

[Exocer]

Not entirely sure how much volume this tube is good for, but this looks like an easy way to get into DIY and is relatively cheap.http://www.thrilleraudio.com/Detail.aspx?id=478

I would skip this driver all together though, it requires way too large of a box to be at a usable Qtc. (.5-.707 IMO) in general.

[brent_s]

Dennis,

how large of an enclosure can you live with (dimensions)?
Can you handle multiple smaller enclosures (how many)?
How large is the space? Primary listener distance to planned sub location(s)?
What processor/speakers are you using it with?
Do you know your typical listening levels in either peak SPL or relative to reference calibration?
What are you going to power the DIY subs with...you only mention a budget of $100 for the drivers?
Does it have to be a tube or could you build a box or possibly a cradle to lay the tubes horizontal?
Hometheater/music balance? What type of music?

-Brent

[wrenchddm]

Brent The largest size i want to use is the 16x36 listed by Exocer.I could do 2 subs but they would about 20" tall max.Room size 15x11 8 feet tall.2 subs would be about 7 feet in front and to the side of me. 1 sub same location or 3 feet behind me.Receiver DENON AVR-2803.speakers are HBX 4 3way towers,2 bookshelf,2way center.do not have SPL meter.Level slightly louder than normal regular TV.90% TV & Movies.Amp.(http://www.partsexpress.com/pe/showd...number=300-806) thought would use this.Want to build tube. Box would take up too much floor space.Tube has to stand up.If i build a single unit instead of a dual want to make it top fire not down but would like a dual.

[brent_s]

Hmm...you're budgeting $240 for the amp (sale price), but only $100 for driver(s)? Not the design tradeoff I would make. So in reality, that gives us a total budget of $340 to work with, non? The possibilities are expanding.

-Brent

[warnerwh]

You may be better off using a larger driver of high quality and Xmax than 2 cheaper drivers.

[brent_s]

Thanks to Apex Jr, you could build a clone of M&K's VX-1250 for $210 + shipping + enclosure. In a 16" tube, you'll want 30" between end caps to net the 3.25 ft^3 needed by the driver. Doubling .75" material for inset endplates on that Thriller tube would give you a net 16"x33" = 3.8 ft^3, which may be a little on the large size. If cutting off 3" isn't an option, you could try this driver/amp at 3.8...if you don't have a bottoming problem, you're done. If you do run into bottoming due to the oversized enclosure, you could use something like sealed plastic soda bottles to displace the extra 14l/.5 ft^3 inside the tube.

Sitting at 3' from the sub, you should have ample output if your SPL needs aren't extereme.

I do have to ask, why upfiring? That sounds like a recipie for driver damage with such a low enclosure height.

-Brent

[brent_s]

Dennis, are you set on a sealed sub for some reason? Would ported be an option if it still fit your size and budget?

-Brent

[brent_s]

The Quattro 15 in the 16"x36" tube with 1.5" endcaps for a gross volume of 3.8 ft^3. Estimate a net with driver of 3.65 and you're looking at nice low Q of .696 with an f3 of 37hz, f10 of 22hz. Ground plane at 1m...99dB@20hz, 107dB@30hz, and 110.6dB@40hz. Should work nicely with even a mild amount of room gain. This used to be *THE* recommended budget build on some forums and generally receives high marks from those who have done it. I'd power it with PE's BASH 300. Amp + Driver = $223 and PE's currently running free shipping.

I was trying to figure out a way to take advantage of the 1259 motor based drivers that NHT is liquidating for $20/$30. However, with the current sales price of $74, this option ends up being simpler, IMO, and offers virtually identical peformance to using a pair of 2ish ft^3 enclosures with a $30 NHT in each.

From 20-40hz, a single Q15 with 300 watts has virtually the same SPL as a pair of the EHQS12s in dual 2.3 ft^3 sealed cabinets with 100 watts each. The EHQS12's f3=50hz, f10=28hz, so unless you have gobs of room gain, it won't be as flat in room as the Q15.

FWIW, based on my listening habits given your room placements, from 20hz up the Quattro 15 probably has enough SPL for 95%+ of my needs. If you want more output, a ported 12" is probably the only option given your budget and size contstraints. Something like the RS12-HF or DVC12 ported in that enclosure will get you 3-6dB more in the 20-30hz range, but the Q15 catches up and moves ahead around 40hz.

-Brent

[wrenchddm]

wanted the better amp for when i can build a bigger sub to replace my end table.also the PE had a EQ built in.not worried about upfiring was going to put a raised cap on it.plus my floor is raised wood subfloor with carpet thought it would kill the sound.never gave ported a thought .they all looked too big.if dual is out.could build a ported sub.cutting the tube would be no prob. thanks for all your advice. Dennis

[brent_s]

The max SPL difference between 300 and 500 watts with a given driver is less than 3dB. The single band PEQ could be beneficial. However, in thinking of the design as a system, given the budget constraints, the $100 upcharge is not justified, IMO. If, after you get a sub running and find you have an uneven frequency response, you can get a BFD for $100...more more flexible than the single band on the HPSA.

Neither of your current enclosure volumes is large enough to optimally use dual drivers, IMO. The 16x36 would probalby work acceptably with the $30 NHT drivers, but as I said, there's no performance advantage over a single Quattro for $74...with shipping costs added, the Quattro is probably cheaper.

If you're already thinking of a larger and/or more expensive solution in the future, the best allocation of funds might be doing nothing right now. How does the PSW1000 in your other thread play into this? The sealed Quattro15/BASH 300 may not require an upgrade, given your room/listening habits description, but only you can make that call.

Actually, if that end table will give you the space for something that'll net close to 6 ft^3, the Q15/BASH 300 would still be a good package. In 6 ft^3 tuned to 20hz, you've got an f3 of 21hz. 1m ground plane numbers are 109dB@20hz, 112dB@30hz.

-Brent

[wrenchddm]

the single unit is fine.as for the PSW-1000 at first i was going to build one and see witch one i liked the best then give the other one to my son.but i can not find the OHM of the speakers so i don't know weather to wire then in Series or Parallel. so i may do nothing with it right now.if i build a ported sub will it still fit in the 36" tube & do you think a down fire will work? the next sub will be built at least a year or more from now only if i need it. i don't want to build something that large for my first build.

[wrenchddm]

just orderd the tub from Thrilleraudio. should be here in a few days.will order the rest on monday or tuesday. if you let me know what size port i will order it from PE at the same time.think i can make the port flares from MDF. will just make a center brace for the inside flare.

[brent_s]

So you want to do a ported sub in the 16"x36" tube? That's too small to port the Quattro15. You'll need to step down to a 12" driver like the DVC12 or RS315-HF.

-Brent

[wrenchddm]

O\K with either one. witch one would work best? will down fire work on my floor?

[brent_s]

Alright, here's a direct comparison of SPL and Response curves. Using a 16x36 tube with 1.5" endcaps for a gross of 16x33=3.8 ft^3. I modeled the DVC12, RS315-HF, db500-12, and EHQS in 3.55 ft^3 using a full 4" Precision Port...effectively 4"x17". The Quattro15 got a 3.65 ft^3 sealed box. All except the EHQS12 got 300 watts...it can only handle about 100 watts.

DVC12 = Orange...RS315-HF = Yellow...db500-12=green...Quattro15=pink...EHQS12=blue

The db500-12 is essentially the same driver used by SVS in their Plus series until early/mid 2006. It's available as the Mistral 12 SVC from Torrent Audio for $115. With this option, you'd pretty much be building a slightly underpowered SVS 20-39Plus. I know nothing about Torrent as a vendor, caveat emptor.

Based on the flatness of the curves and other project reviews, I'd go either RS315-HF or db500. If budget is a real concern, I don't think real world use of the Quattro15 would give up as much as the models suggest. I lived with a pair of sealed 12" drivers for 13+ years and replaced them with a big ported DVC15. In room frequency response measured with REQW is about the same...the DVC15 is capable of much more output than the sealed boxes, but in reality, it just means the DVC15 isn't working as hard to deliver the SPL levels I listen at.

FWIW, I've got cabinets for both a RS315-HF and an SVS db12.1 sitting in the workshop, both drivers and a BASH 300 sitting in the project closet...I just haven't put the two together yet.

-Brent

[brent_s]

Subwoofer wavelengths are so long, firing directly into the carpet is of minimal concern...hence the number of commercial designs that use this approach. However, there's certainly nothing wrong with using SVS' approach of a bottom plate. My DVC15 is forward firing with a bottom port firing directly into the carpet. I've taken measurements with the sub on its side so the port is firing into free air as well as it's normal orientation and there's no difference around the 17hz tuning frequency.

-Brent

[brent_s]

On that PSW1000, Polk should be able to tell you the proper wiring configuration when you call about the replacement amp. Most likely, they're 8+ ohm drivers, wired in parallel...at least that's the approach NHT uses for their dual driver subs. Most plate amps don't like going below 4 ohms so the drivers would have to be wired in series if they were under 8ohms. Is there no wiring left to clue in how it was configured?

Probably should ask this in your Polk thread, but how did the seller come to have the PSW1000 without an amp? Hope you got it cheap in case the drivers are actually damaged in some way.

-Brent