Dayton Reference 12" HF

[npdang]

What a beautiful, and surprisingly heavy 12" driver. The cone is a true anodized black aluminum, and not painted. The rubber gasket also runs only along the top of the driver, similar to the old style cork gaskets, and while it looks great it doesn't help to provide a seal with the baffle.

Looking at the heavy cast frame, you can see alot of attention to detail in this woofer. Notice there are venting holes not only under the spider and through the pole, but in the gap where the voice coil sits as well! And upon closer inspection, you can see the thick copper ring on the outside of the gap. I'm assuming from Partsexpress literature, that there's also another copper ring above and below the magnetic gap. Wow :)

Breaking this driver in with pink noise, I also noticed very little rub/buzz and mechanical noise. However, the cone breakup was very clearly audible giving a noticeable metallic coloration to the sound. I only mention this to discourage anyone from using it as anything but a subwoofer, even though inductance is astonishingly low. Looks like a great candidate for IB use.

http://diymobileaudio.com/pics/daytonref12hf/pic1.jpg
http://diymobileaudio.com/pics/daytonref12hf/pic2.jpg
http://diymobileaudio.com/pics/daytonref12hf/pic3.jpg

Very nice... Le actually measured half of what was spec'd. Efficiency right on spec as well. Ripple at ~1.6khz ... sign of the first breakup mode. Vas of 87L will probably mean a large size sealed box.

http://diymobileaudio.com/pics/daytonref12hf/impedance.JPG

Free-air, unbaffled nearfield frequency response @ 2.83Vrms.

http://diymobileaudio.com/pics/daytonref12hf/fr.JPG

Very nice curves. Bl is indicative of a well designed underhung driver with a smooth flat plateau and gently sloping ends. Centering is a tiny bit off, but not a big deal. Kms curve is almost perfectly symmetrical and centered. Excellent design.

The inductance variation is also one of the best that I've measured in any driver, with only about + 8%/ - 15% variation through it's entire operating range. Looks like the triple copper rings have done their job.

I'd put 1 way xmax right at 14mm, exactly as rated... although the driver has quite a bit of mechanical throw that's not being used.

http://diymobileaudio.com/pics/daytonref12hf/klippel1.JPG
http://diymobileaudio.com/pics/daytonref12hf/klippel2.JPG

I really like this driver. It's very well designed and executed. Although 14mm of 1 way xmax isn't anything special these days, within it's limits the driver performs admirably and in my experience so far without peer. Especially when you factor in the price of $119 per unit.

[mk1982]

dayton does it again !!

[werewolf]

Another excellent review. You guys already know this, but man Dayton must now be recognized as a true frontrunner in the world-class driver market, and the absolute tops for value :)

[theNoid]

Dayton is indeed a true contender for high-quality audio equipment. Throw in the price/performance factor that just makes them even better in my book.

Noidster

[npdang]

I'll be posting the Peerless 830845 xxls 12" results in a minute. It's pretty much just as good as this one, if not perhaps a slightly better Le vs. x curve and better centering on the bl.

[kappa546]

oh man... nice looking driver

[theNoid]

I'll be posting the Peerless 830845 xxls 12" results in a minute. It's pretty much just as good as this one, if not perhaps a slightly better Le vs. x curve and better centering on the bl.

I would hope so considering it's roughly $155 dollars for one.

Noidster

[fugyaself]

I was hoping these did as good as they looked like they would.

Definately a XLS/TC2+ contendor.

I do believe one of these will make its way into my car.

[ArcL100]

Mmmm thanks for the review!

One of these running IB could complement the RS 8's in the doors :D

-aaron

[newtitan]

Especially when you factor in the price of $119 per unit.

wheres this 119 link?

[npdang]

I'm sorry $129 :P

[capslock]

couple of comments:

- malcentering of Bxl is about 2.5 mm - not really a trifle! considering that compliance is well-centered, the coil needs to go into a different production (edit: meant to write position), something that can be fixed in manufacturing quite easily - have you contacted Darren on this?

- are you sure the motor is underhung? the top plate doesn't look like it is 20 mm thick - maybe it is middlehung, i.e. thinnish top plate but very long cylindrical pole piece?

- negative displacement means cone goes in? so inductance goes down as the cone moves towards the magnet? this is a case of too much Faraday shielding below the top plate and too little above - this driver could use a more massive ring on the top side of the pole piece!

- what frequency is used in the inductance vs. displacement measurement? for a sub, inductance vs. displacment is not that important, surpressing magnetization modulation is more important (whích is probably why there is more shielding below than above the top plate) -- is there a way to measure this with the Klippel system?

[npdang]

Some good comments there.

For a sub, I generally do not consider a few mm off centering much of a big deal due to the long coils and our insensitivity to second order distortion at those frequencies.

As far as the motor, I did not want to give the impression that it was an underhung motor... only that the bl curve has the "appearance" of being one.

This is the only info I could find in the manual with regards to Klippel measurement:

"An electro-mechanic equivalent circuit with lumped elements can model electrodynamic transducers at low frequencies successfully"

"The Loudspeaker is measured in a normal operating mode while reproducing noise. Optimal parameters are estimated by nonlinear system identification based on adaptive inverse control. Using back EMF detection the information is derived from the voltage and current available at the loudspeaker terminals..."

Not too useful... if anyone has any links that maybe more informative I'd love to see them. About the only thing I could gather from that was "noise, low frequency stimulus", "measured current/voltage at the speaker's terminals", and extrapolated parameters based on an electro-mechanical model.

[werewolf]

I'll give it a shot, and provide some good references :)

We want to determine some standard parameters for a loudspeaker under-test. The first thing we need is a good "model" for the speaker. It has been shown, largely through the groundbreaking work of Beranek and later Small, that a loudspeaker working in it's piston range is accurately modelled by an electrical equivalent circuit, where the various circuit elements represent the electrical, mechanical & acoustical elements of the actual speaker. So we know the "form" of the electrical model for the driver ... we just need to figure out the values of the various elements to represent the exact driver being tested. That's what's meant by an "electro-mechanical equivalent circuit with lumped elements can model electrodynamic transducers at low frequencies successfully."

OK so we have the circuit form, how do we assign each element in the model the correct value, to accurately represent the speaker under-test? A great way to do it, at least conceptually, is to drive the actual loudspeaker with a test signal ... perhaps noise ... and measure it's real output. You may measure the output with a microphone, a laser, or just the voltage/current at the speaker leads ... depending on what info you need. Now here's the real trick .... what you need to do, probably through computer simulation, is to drive the electrical model of the speaker with the same stimulus. Then, you adjust the value of the circuit elements in the model until you null the difference between the real speaker output and the output of the simulated model. When a null is achieved, you have assigned the correct value to the elements in the model. This is a simplified explanation of "adaptive inverse control" used for system (loudspeaker) identification & modelling.

What you'll see in the following links is several pictures of a real speaker driven by a certain stimulus, in parallel with a circuit model of the speaker driven by the same stimulus. When the difference between the two is driven to zero (or very small), the model accurately represents the speaker and you have the element values you were looking for. Of course there's complications, mostly due to large-signal nonlinearities ... which basically means that the circuit element values (that represent the speaker) change as the stimulus amplitude increases.

http://www.klippel.de/pubs/default.asp

In particular, check out :

The Power of Loudspeaker Models
Fast and Accurate Measurement of Linear Transducer Parameters

[Nothingness]

Which sub is best used to 200 or 300hz?

[jdybnis]

The tests show that both this and the XXLS will perform excellently with a 4th order crossover at 250Hz. Consider the 10" versions of the driver too. It will make the crossover easier. The 10" will give you more breathing room before the first breakup node and also before the driver becomes less omni-directional.

[capslock]

I saw a Klippel system once at an audio fair, and it was equipped with a laser displacement sensor, possibly also with a calibrated mechanical actuator.

After going back to the spec, I now realize the Klippel system can be operated without either (i.e. with just the distortion analyzer box & software), and will still calculate Bxl and suspension compliance curves. Is this how these curves were generated?


Knowing how many nonlinear parameters there are in a loudspeaker, I would tend to suspect that a rest position calculated just from impedance data and acoustic measurement can easily be off by a couple of mm. Then of course, there are mechanical hysteresis effects such as suspension creep, and this in combination with a non-symetrical inductance vs. displacement curve may result in the "zero" position being different from DC at various frequencies. Maybe the Klippel calculates an AC rest position, but at what frequency and drive voltage?

[jdybnis]

npdang, capslock,

Can you explain to me what causes the "inductive hump" in bass drivers? I see the Dayton has a bit of one and the XXLS doesn't. But the Dayton's Le is less than half?

[capslock]

what exactly to you mean by inductive hump?

[jdybnis]

I'm refering to the bump around 70Hz followed by the dip around 200Hz. I see this frequently on the FR of high excursion subwoofers. It seems to be more pronounced on drivers with higher Le. On the Peerless thread you make note of the absence of it on that driver.

Thanks.

[jamesavery22]

would you guys take a dayton 10hf over a arc audio kar10? Both are the same price, 119$.

[10K2HVN]

would you guys take a dayton 10hf over a arc audio kar10? Both are the same price, 119$.
i havent heard either, but id try an RefHF before id try an KAR sub...

[jamesavery22]

bump... any other opinions?

[jkrutke]

couple of comments:

- malcentering of Bxl is about 2.5 mm - not really a trifle! considering that compliance is well-centered, the coil needs to go into a different production (edit: meant to write position), something that can be fixed in manufacturing quite easily - have you contacted Darren on this?

First post here. I'm not the biggest car audio fan, but I can certainly respect the extensive tests shown here, particularly the Klippel stuff.

Regarding the malcentering of Bxl, does anyone think this could be caused by cone sag? If it is, that should gradually improve over time if mounted vertically. With some drivers, I've noticed that cone sag doesn't go away with a little breaking in, but rather it takes upright mounting, lots of usage and a long time.

If it's just due to construction, I have to agree with capslock that 2.5mm isn't exactly a small number.

npdang: can you see any sag in the spider in resting position? If you see exactly 2.5 mm worth, I think the whole Bxl issue is a non-issue.

Ps. That backplate kinda looks like the one on the MCM 55-2330. I'm sure the 2330 motor internals are nothing special however.

[blackreplica]

Hi John

Its nice to see you here, it's kevin here, the guy who emailed you about this forum. Hope we'll see more of your thoughts here as well :)

[AJinFLA]

Hi John,

welcome aboard :) . Don't want to drift too far off the thread here, but is the MCM 55-2332 in any way related to the 2330 in your pic? Highish Fs and no Le listed :confused: , but looks good otherwise. Have you tested the 2330?
Do you think it might be anywhere near the XLS/XXLS or Dayton in terms of value/performance? Thnx.


Cheers,

AJ

[jkrutke]

Its nice to see you here, it's kevin here, the guy who emailed you about this forum. Hope we'll see more of your thoughts here as well :)

Thanks for the tip, Kevin. I took a look back when you emailed me about that, but another recent look reveals tests on this Dayton sub I've been drooling over. :)



welcome aboard :) . Don't want to drift too far off the thread here, but is the MCM 55-2332 in any way related to the 2330 in your pic? Highish Fs and no Le listed :confused: , but looks good otherwise. Have you tested the 2330?
Do you think it might be anywhere near the XLS/XXLS or Dayton in terms of value/performance? Thnx.

Hi AJ. I haven't tested the 2332, but I have tested the 2330, since it was sent to me as a test sample. It sounded ok, but the build quality was seriously lacking. The frame was cheap and thin for such a massive magent, and the surround was coming unglued at the frame. Le was massive, indicating nothing special in the motor dept. On the bright side, low Fs, very usable T/S parameters, and almost no wind/port noise at full 13mm excursion. Overall however I was unimpressed and gave it away to a friend. (who thinks it's the best sub he's heard in his life)

With the 2332, at that price, if it even works at all it's probably a good deal. Anyone notice that cheap woofers like this all use the same frame? The spider mounting ring has several levels to accomodate all options. Looks like the new Daytons use the same frame. Commodity woofer parts are a dime a dozen. The difference in cost between the Peerless and the Dayton is probably all in the frame. I still fully expect these new Dayton subs to be the value leaders. I watch this thread with interest.

[AJinFLA]

I have tested the 2330, since it was sent to me as a test sample. It sounded ok, but the build quality was seriously lacking. The frame was cheap and thin for such a massive magent, and the surround was coming unglued at the frame. Le was massive, indicating nothing special in the motor dept. On the bright side, low Fs, very usable T/S parameters, and almost no wind/port noise at full 13mm excursion. Overall however I was unimpressed and gave it away to a friend. (who thinks it's the best sub he's heard in his life)

John, with comments like that you might be liable not to get too many more "samples" from MCM :rolleyes:
Luckily no one there is perusing this site as of yet, but with Klippel testing taking place here, that may change! NP is probably in for a lot of requests to test all sorts off drivers, from lots of different folks, maybe even some of those wacky megabuck fullranges ;) .
Is it possible that the malcentered coil is a review sample issue? Possibly a manufacturing defect? Dayton has had issues with other drivers. Just a thought.

Cheers,

AJ

[npdang]

I have no problems providing free Klippel testing. In fact the unit was donated to me by a very kind and generous individual, for the benefit of the DIY community. The test is rather quick to setup, and takes about 20 mins to finish the non-linear mode.

As far as cone sag.. I'm not noticing any. I could retest the driver at a later point in the vertical position if that's a concern.

Fwiw, I've been a huge fan of Zaphaudio for awhile now. I used to own SoundEasy and I really enjoyed reading John's tutorial.

[Feyz]

Question for npdang, do you have the optional Laser displacement sensor with the Klippel? From what you wrote, it sounds like you are not using it, you had the driver horizantally lying if I read correctly which is not the position to use the laser from pictures of Klippel's device on their website. So if no displacement data is supplied, do you enter a constant Mms value for nonlinear measurement mode? Or does Klippel calculate Mms at small signal with added mass (or closed box method) and then this value is imported to the nonlinear measurement mode as a constant?

The reason I am asking this, without additional data from either a laser, accelerometer or microphone, the actual values of Bl, Cms, Rms and Mms can't be determined from just voltage and current (which is impedance data in the end) taken from driver terminals. If one of these parameters are entered by the user or imported from another place, the other three can be calculated just from voltage and current data. The most suitable one to be considered constant with displacement amoung these four parameters seems to be Mms. That's why I am guessing Mms is being entered as a constant.

[npdang]

I do not have the laser. I import bl at x =0, as recommended by Klippel. As well as the parameters you listed, it directly impacts the x scale.

[454Casull]

Does anybody have all the T-S parameters for the 12" high-output version?

[ludlamtheory]

im curious... has anyone compared the HO to the HF sonically?

[sprtwin1]

Hello, I am on the hunt for a good priced sub woofer that is extremely fast in a sealed enclosure. I am fed up with my current sub because although it sounds good, it cannot keep up with the extremely quick notes found in some of my music. I am currently looking at the IDQ12V3 or just the ID12V3, but I would much rather save some money if this dayton is quick enough. So how would you guys compare this to the Image Dynamics subs? Would you guys happen to have any recommendations of other fast subs? Thanks in advance.

[theothermike]

im also extremely intrested in what the main difference is between HO and HF.

Obviosly the HO has 3mm more xmax over the HF, but the HF takes more power.

However whats the difference sound character wise?

is HF more SQ oriented or are they similar.

[tcguy85]

im also extremely intrested in what the main difference is between HO and HF.

Obviosly the HO has 3mm more xmax over the HF, but the HF takes more power.

However whats the difference sound character wise?

is HF more SQ oriented or are they similar.

i have the HO ten and absolutely love it. the ho's take more power and require a smaller box. i have it in .7net tuned to 30hz and it is tight as hell. i have never heard a sub sound so fast and tight.

search in here about the daytons subs and you'll find a ton of info on the ho ten. chad did an excellent long review on the 10 ho as well.

[jp88]

im also extremely intrested in what the main difference is between HO and HF.

Obviosly the HO has 3mm more xmax over the HF, but the HF takes more power.

However whats the difference sound character wise?

is HF more SQ oriented or are they similar.


There is only a 2mm difference in xmax between the HO and HF 12 vs 14 respectively

I also have a HO 10, Mine is currently in .75 sealed with .5lb of poyfill. I am very satisfied with it so far.

[typericey]

The Dayton HF/HO lines and the DLS Iridium/Nobeliums look amazingly similar. Would anybody have insider info if they are indeed related? (Tho DLS is very famous for copying designs)

[drocpsu]

As others have said, the HO requires a smaller box. I am using an HF in a sealed box for a home theater sub, and the thing is huge. My buddy designed the box to WinISDs specs, and it's really big.

[envisionelec]

The Dayton HF/HO lines and the DLS Iridium/Nobeliums look amazingly similar. Would anybody have insider info if they are indeed related? (Tho DLS is very famous for copying designs)

I am unsure if DLS copied the Dayton. I personally know the designer of the Dayton, and he hasn't done work for DLS.

[X Ray]

im also extremely intrested in what the main difference is between HO and HF.

is HF more SQ oriented or are they similar.

The main difference is that the HO models have 4 layer voice coils and the HF models have 2 layer voice coils. Do the math, the 4 layer voice coil allows the HO models to be used in smaller boxes, but Le goes up.

The 2 layer voice coil is better for sound quality, but requires that the speaker be used in a larger enclosure. You lose some power handling as well.

[Tommythecat]

The main difference would be the fact that the HO has a VAS of 1.62 cu.ft. while the HF has a VAS of 3.00 cu.ft. This is only directly related to suspension compliance.

What math should I do now?

[X Ray]

The main difference would be the fact that the HO has a VAS of 1.62 cu.ft. while the HF has a VAS of 3.00 cu.ft. This is only directly related to suspension compliance.

What math should I do now?

So Vas is the main (most relevant) difference in your opinion? Are you aware of the differences in the motors???

[Tommythecat]

If we're talking about box size requirements - that is the only thing I need to look at. If you want to talk about anything else we can talk about those relevant parameters.