Dayton RSS315HF-4 vs Peerless XLS/XXLS for a sealed sub?

[Maximiliano]

I think I need advice from experts here. I want to build a subwoofer for my 80/20 music/HT system. I want to cross this sub with my 6.5" sealed 2-ways at 80 Hz. The sub will be placed in front between the speakers. Room is not big (12 by 14 ft). I don't listen very loud. So my primary goal is SQ for music listening and a good blend with my satellites.

I initially thought about using Dayton RSS315HF-4 in a closed 2 cu ft cabinet---I did before the Dayton RS1200 project was published.

Then I read about Joe Rasumussen's Critical Q Subwoofer and Linkwitz's Thor designs. They both use the Peerless XLS 830500 woofer in a closed cabinet of a similar volume. Box Qtc is about .5. Sort of between IB and .7 Qtc closed subs. I thought I could use the O Audio 500W plate amp because its subsonic/EQ filter and PEQ would be useful to set it up.

Now I have to decide between these two designs. Which one do you think will be better to achieve my goal? The Peerless is almost double the price of the Dayton. I wonder if the Peerless design will be worth the additional cost.

BTW, I simulated the responses of both designs using Unibox. Other than two designs' different rolloffs, I couldn't judge which will be better in my situation.

Thanks in advance,

Max


Edit by moderator to add
The person posting as Maximiliano is actually Woe Jay Kim

[ThomasW]

Depending on how much you want to spend, I'd use either the Aura NS12-513-4A, or the PE RS315-4.

The Peerless XLS isn't in the running given it's Le.

[Dennis H]

There's probably not a huge difference below 80 Hz. They are both very good. Monte Kay tested the Peerless and the Dayton and the Dayton did better overall.

https://web.archive.org/web/20080101132510/http://www.mfk-projects.com/woofers.htm

Monte talking about the Dayton:

Anyway, one amazing thing about this woofer is its ability to perform well up to several hundred Hz. This is a little unusual for this kind of heavy high excursion driver.

(snip)

It seems about as good as the XLS in the mid bass region with some frequencies possibly better on the XLS and others better with the RS. Generally the two are close in the mid bass region. The RS is better at very low frequency and will also be better than the XLS at frequencies above 100 Hz.

[Maximiliano]

The Peerless XLS isn't in the running given it's Le.

May I ask why? Sorry about my ignorance. Why not high Le?

[Maximiliano]

There's probably not a huge difference below 80 Hz. They are both very good. Monte Kay tested the Peerless and the Dayton and the Dayton did better overall.

https://web.archive.org/web/20080101132510/http://www.mfk-projects.com/woofers.htm

Monte talking about the Dayton:

Thanks for the good information, Dennis.

BTW, is there any benefit I can get from the low Qtc of the Critical Q sub design? According to Joe it seems that "critical damping" is his selling point that makes a non-servo design achieve the low distortion performance of a servo controlled design. But I don't fully understand his argument.

[ThomasW]

The "Critical Q" appears to be yet another example of someone taking a standard design, renaming and giving it magical 'new' performance characteristics.... :roll:

Critically damped alignments, (aka sealed boxes with a Qtc= 0.5), have been around quite a while. Do they replace servo subs? I doubt it since IMO that's an apples vs oranges type of comparison.

If Joe R. want's to post actual performance comparison between his design and a comparable servo system that would be interesting....

FWIW the Aura Sound 12" has the lowest distortion of any 12" driver JonMarsh has ever tested. He's tested the RS315 and it's quite good, but not as good as the Aura 12".

[Maximiliano]

FWIW the Aura Sound 12" has the lowest distortion of any 12" driver JonMarsh has ever tested. He's tested the RS315 and it's quite good, but not as good as the Aura 12".

Yeah, I just looked at Jon's distortion measurements. To me, the Dayton's performance looks better than the Aura below 150 Hz, which is important as these are subwoofers. Perhaps, you're confused with the two tests' different SPL scales?

[ThomasW]

Yep I got confused, (posting on different forums at the same time tends to do that) but it was regarding application not frequency response.

Run with the RS315...

[Mazeroth]

I second the RS315HF, in as large an enclosure as you're comfortable with. Right now is a great time to purchase one due to them being on sale for $20 off. Also, that O Audio 500w BASH amp looks like a pretty good deal for $229, considering the one at Parts Express is the same price and lacks the parametric EQ feature.

One other option, if you're looking to save money and maximize in-room response, would be to drop down to the 300w BASH amp (which will only drop your total maximum output by ~ 2 dB) and pick up a Behringer Feedback Destroyer (new or used) to get a more controlled frequency response.

[Maximiliano]

My listening room is not that large. So my hard limit is 2 cu ft due to WAF. In this cab, the RSS315HF gives about .7 Qtc where as the Peerless gives .5 Qtc in a 1.5 cu ft cab. I wonder if a smaller Qtc will provide any advantage in my setup.

In terms of nonlinear distortions, both RSS315HF and XLS are excellent performers according to Monte's tests. Overall, the RSS315HF's 2nd order harmonics are a little lower than the XLS's, and the other way around for the 3rd order harmonics.

[ThomasW]

Sorry for my brain freeze yesterday, a cocktail of migraine meds had me posting dipole driver answers to your thread.... ops:

There's no benefit to going lower than Qtc 0.50

Using a single 12" with only 12mm of Xmax is an invitation for distortion problems that occur beyond those measured with small signals in a test situation. Note that Rasmussen recommends using 2 of the XLS drivers

So.....

In the real world were I limited to a single 2 cu ft box, I'd build with this driver or one similar.

https://web.archive.org/web/20081104020318/http://www.soundsplinter.com/rlp12_subwoofer_information.html

Having driver headroom available is important when running digital sources given the huge transients that can occur...

[WillyD]

Honestly, just go with that RS1200 kit. Your room isn't that big, you say you don't listen loud, and you are primarily listening to music.

Another option with 2ft^3 is to use two RS 12 HOs. That'll give you a Q of .58, and a good bit more output than the single RS.

[soho54]

Still kicking myself for not buying more of those OAudio TC2+ 12"s from the last batch.

Sorry, seeing the RL-p12s again hit a nerve. :B

[ThomasW]

Honestly, just go with that RS1200 kit. Your room isn't that big, you say you don't listen loud, and you are primarily listening to music.

There's very little headroom with a 12" having a lowish Xmax, if he's okay living with that limitation fine...

The other situation with a single RS315 or Peerless XLS is one's hamstrung when it comes to EQing it. There's simply no headroom for the EQ. And IMO operating in a 2 cu ft box EQ will be mandatory if he wants anything other than 'boom' .....

Another option with 2ft^3 is to use two RS 12 HOs. That'll give you a Q of .58, and a good bit more output than the single RS.

Overall that will force a physically larger box given the gross vs net adjustments needed to accommodate the second driver.

If he wants a reasonable amount of headroom in a small box, he needs to look at a 12" with more Xmax.

[WillyD]

There's very little headroom with a 12" having a lowish Xmax, if he's okay living with that limitation fine...

Yeah, very little headroom in the lower frequencies for sure. But this is only being used as a music sub correct? And in that RS1200 kit, the amp used has a highpass at 18Hz. The output in the 18-30hz range would be a bit limited sure, but should be plenty for the OPs needs.

Overall that will force a physically larger box given the gross vs net adjustments needed to accommodate the second driver.

The second driver wouldn't add that much. He could live with the same size box and an ever so slightly higher Q. Two RS 12 HOs in 50liters and a Qa of 20, gives me a Qtc of .6. Using the two HOs would give the OP at least a 5dB increase at 20Hz, for instance. And that would be in a smaller box (40 liters for the two HOs, vs 56 for the HF).

If he wants a reasonable amount of headroom in a small box, he needs to look at a 12" with more Xmax.

Absolutely.

So my primary goal is SQ for music listening and a good blend with my satellites.

I think sometimes we forget our perspective. You have a monster IB, so a single 12" seems like chump change to you, rightfully so. It seems small to me as well (high excursion 15") yet you have someone like Zaph who only listens to music without a sub, and pulls his RSS315 out for 'video' use.

Oh, there are also some 12" TC-2000 D4s still for sale. http://www.tcsounds.com/products.htm

A pair of those in 50liters? Qtc of .5 They'd practically be limited by how much power the OP could give them, not their displacement limitations. They'd provide maybe 10dB more at 20Hz than the single RS HF would, powered correctly.

[ThomasW]

I have a single 12" sub (20mm of Xmax) in the bedroom where it belongs...

His target is 80/20 music/HT, so IMO using a single 12" with 12mm of Xmax is a stretch.

His focus is having a Qtc 0.5...can't say I blame him there... :T

BTW I haven't lost perspective.....yet... :B

[WillyD]

I have a single 12" sub (20mm of Xmax) in the bedroom where it belongs...

:rofl:

His focus is having a Qtc 0.5...can't say I blame him there...

No doubt!

His target is 80/20 music/HT, so IMO using a single 12" with 12mm of Xmax is a stretch.

So how about two 28mm xmax 12"s?

External enclosure dimensions of 14in x 14in x 18in. I think that'd work.

TC-2000.

[Maximiliano]

Thanks for the help, Thomas and Willy.

As I said, my main goal is SQ for music listening. If I had built a nice 3-ways with hi-fi woofers (not subwoofers) that can go -3 dB at 35 Hz, I would not have considered adding a subwoofer even for occasional HT use. That's me.

If there's no benefit I can get from using the Peerless, I'll go with the RSS315HF.

BTW, for your information, the Dayton HPSA500/1000 sub amps have a serious design flaw. It generates very audible, high-frequency harmonic type noise with input signals. PE would not want to admit it but I and another guy at PE forum reported the same problem and PE is now investigating it. I initially thought the problem was in my setup, but it turned out not. A technician at PE was able to replicate the problem. I'm not sure whether PE will eventually decide to take some action about it or not. But I'm now 99% sure that this amp has a flaw.

I think the reason why this issue has not been reported yet by the users is that a) The amp works; b) In real-world situations, it’s not always easy to hear the distortion when you are running full-range speakers along with the sub (a bass-guitar solo is another story, though; that situation sounds like crap); c) Most people have their subs tucked away in a corner, behind a couch, etc.

Anyway, I'm going to use an O Audio Bash amp.

-Max

[soho54]

the Dayton HPSA500/1000 sub amps have a serious design flaw

I missed that little conversation. Can you link to the thread?

EDIT: Never mind I found it. Good thing you use the same pen name.

[Jim Holtz]

I'm one of the folks that can't hear the distortion that Max is talking about. I had Stryke AV12 (TC Sounds) 12" subs built into each cabinet of my line arrays and both were powered by PE 500 watt amps. I crossed them at 70 Hz. without filtering the line arrays. They rolled off naturally and I used the built in 24 DB crossover in the amps to control the subs. I also had them connected to the main outs from my preamp using Y cables with interconnects running to both inputs on the amp.

I have ran test tones, yada, yada, yada and have never heard any bass distortion. Quite the contrary, actually. Rick Craig even came to my house and set the subs up to blend with the arrays. I've had a minimum of 70 people at my house over the last three years and the one comment always made was how great the bass was.

I've since moved the linearrays to my store room waiting to be sold so I'm not going to do any more investigation but I am convinced that the distortion is either a new flaw (mine are from the original batch) or it has to do with getting the signal out of the LFE output and not using the internal crossovers. I have a friend that has two recently purchased 1000 watt rack mount amps powering (4) TC Sound 15" subs from an Outlaw 950 that also doesn't hear the distortion. I'm not sure what in Max's setup is causing it but I'm not convinced that it's the amps.

I'm not trying to argue with Max as we didn't agree in the PE thread but it's simply not my experience. I do know that if PE has a problem with the current batch, they'll make it right.

FWIW

Jim

[Maximiliano]

Hi Jim,

You're not arguing with me at all---you already admitted a possibility of the amp's flaw when it's used in a different setup from yours.

Have you really tested your amp exactly following what I suggested to you at the PE forum?

Anyway, one thing clear for now is that the current production batch (both HPSA500 and HPSA1000) has this problem. Several amps tested at PE and the rack mount version a guy at PE forum owns exhibited the same problem. I heard that an amp was sent to the company that engineered it.

BTW, let's not talk about this issue here any more. I just wanted to give information to potential buyers of these amps.

P.S. Thomas, if you think this issue is not appropriate for this forum, let us know. Thanks for your work!


Any more input/suggestion for my subwoofer choice?

[Rick Craig]

There's very little headroom with a 12" having a lowish Xmax, if he's okay living with that limitation fine...

The other situation with a single RS315 or Peerless XLS is one's hamstrung when it comes to EQing it. There's simply no headroom for the EQ. And IMO operating in a 2 cu ft box EQ will be mandatory if he wants anything other than 'boom' .....

Overall that will force a physically larger box given the gross vs net adjustments needed to accommodate the second driver.

If he wants a reasonable amount of headroom in a small box, he needs to look at a 12" with more Xmax.

I've used two XXLS 12" in a 2 cubic ft. sealed box with the O Audio amp providing EQ for extension and it works great - plenty of headroom. The EQ filter actually reduces excursion below the boost.

X-max figures can be misleading. You can take a program like BassBox Pro and track the excursion in relation to frequency, input power, and spl capability. Klippel measurements also can show how a driver with a large x-max may not be able to reach the stated excursion without a high amount of distortion.

[ThomasW]

Seems to me, 2-12"s in the box is is no different than my recommendation for a single 12" with higher Xmax....

[Maximiliano]

Despite Thomas' concern, now I even consider using a HiVi M12 in a closed 2 cu ft box. This woofer seems really well made and may be a good example of Zaph's argument for lower xmax, better SQ, though I know this may not be generalized without exceptions.

A guy at PE M12 product review page uses this setup and is happy with the result. I know this woofer has only 7 mm Xmax. If I experience a distortion/compression for my occasional, relatively "quiet" HT use, then I will consider adding one more later.

Is this a bad idea?

[Maximiliano]

BTW, no distortion measurements are available for this HiVi M12 woofer. Does anyone use this? If so, your impressions?

[ThomasW]

Despite Thomas' concern, I now even consider using a HiVi M12 in a closed 2 cu ft box.

Is this a bad idea?

It's a good woofer it's not a subwoofer.

Do you really trust the review from a guy named "killa"?

Buy either the 12" XLS/XXLS or the RS315..

[Maximiliano]

According to my Unibox sim, taking the amp's boost and subsonic filter into account, the max possible 1m SPL within the woofer's excursion limit is 100 dB at 80 Hz, 99 dB at 60 Hz, 97.5 dB at 40 Hz, and 96.5 dB at 30 Hz.

Will this be sufficient for music listening in a room of moderate size?

[ThomasW]

Will this be sufficient for music listening in a room of moderate size?

I wouldn't think so. There's absolutely NO headroom to allow for peaks in the music...

[Maximiliano]

Thanks, Thomas. Okay. Now went back to RSS315HF and the XXLS. Leaning toward the RSS315HF...

[jimmy154]

I have the same exact scenario, down to the room size and music to HT ratio. I am choosing between the same two subs, more or less. I chose the XLS so I can achieve a Qtc of .5 in a small box.

I want to build a subwoofer for my 80/20 music/HT system. I want to cross this sub with my 6.5" sealed 2-ways at 80 Hz. The sub will be placed in front between the speakers. Room is not big (12 by 14 ft). I don't listen very loud. So my primary goal is SQ for music listening and a good blend with my satellites.

[JonMarsh]

The HO version of the Dayton is the one to use if you want a small box. Higher MMS, stiffer cone. It's probably a good idea to review the choices out there- it's been a long time since that original discussion in 2007, and new drivers on the market. OTOH, if you get the peerless at a good price, then you can get one with your build and not be mulling over incremental differences in drivers!