Cab for Audio Nirvana 10" Full Range

[knightsound]

Hi Guys,

As Thorsten says in another thread, "The real suprise is AN10 super!! This baby rocks for sure. The TSP are just perfect for reflex and a 3 cu.ft enclosure serves 100%."

Having just picked up a pair of these puppies last weekend I'm keen to build the cabinet. A BR would be quick and easy, some form of TL more challenging and *is it really necessary*? The SPL/Freq graph is attached.

"Scottmoose" suggests the following dimensions (converted to mm) for the AN10's:

"For reference the internal dimensions of the cabinet simmed are:
37in tall = 939.8mm = 940mm
13.5in wide = 342.9 = 343mm
10.5in deep = 266.7 = 267mm
7in Zdriver = 177.8 = 178mm
33in Zport = 838.2 = 838mm

Port: 4" = 101.6 = 102mm
Port length: 5-8" = 127mm-203mm

Port is 3in diameter, 4in long.
0.25lbs ft^3 stuffing from the top 15in down.
plus notch filter"

I'm curious to learn from anyone who has built cabs for these drivers. How do they sound in a simple BR design? Is it worth building a TL type design? What front baffle width, port size, notch filter, and stuffing are people using? Lastly, as I'm a noob to this speaker building malarky, would it be worth placing the driver in an "asymetrical" location in the front baffle?

Lastly, one clarification. I don't have access to the MathCAD worksheets and information as the Chinese net has been too slow to access Martin's website for the past month from Beijing. I'm confused as to the location of the Zport. Should the centre of the port be 178mm from the bottom of the box?

These drivers, wrapped in towels and leant against the wall behind my desk, exhibit beautifully crisp vocals while driven by a T-amp for "test" purposes. I can't wait to mount them in proper cabinets hooked up to a 300B SET. I'm grateful for any advice, particularly from those who already have these drivers up and running.

Kind regards,

James

[Geoff H]

Hi James, I have been interested in this speaker since first seeing it, as on paper, it's very similar to what I am enjoying now.
I think a large sealed enclosure would give the widest freq resp. however Xmax may be a limiter. A good sized BR would take care of that with a trade off in transient response.

It would be a challenge in a small AP, with that Zo peak.

I would keep the baffle wide by current trends, say 450mm.

Unfortunately I haven't heard them yet. No one in my part of the world stocks them, so the above is a bit speculative.

The 3 cub ft sealed would be a good starting point. You can always add a port. One thing for sure, keep the driver high, don't bury it in the carpet and furnishings. I have more roof gain than floor gain.

It will be interesting to see how it works out.

Geoff.

[lovechild]

Hi

here is a thread in a german diy-forum AN10 @ hifi-forum.
I would think you can ask there, if someone can give you a summary in english.

Some facts, the project includes a full set of messurements, TSP and FR (see here), so they where able to seriously modell several enclosure types. They finally build a 30 Liter CB (ca. 1 cub feet) that playes down to 100 Hz and is supported by 2 active subs. For real fullrange Xmax is the limitter, as Geoff sayed, they modelled a 110 liter (ca. 4 cub ft) enclosure, tuned to 40 Hz and the result was an SPLmax of only 89 dB!!! + the need of a quite exessive filter, to tame the rising FR.

Something good, everybody would expect a 10" speaker to be beaming as hell, but the AN 10 seems to do very very well for it's size in the HF section.

Can't say anything about the TL, but would guess SPLmax will be a bit higher than the BR, but also very limited ...

hope that helps.
LC

[bigwill]

I have a pair of large transmission lines that these will fit into perfectly, I'm really tempted to buy a pair.

[Geoff H]

Quoting LC

"They finally build a 30 Liter CB (ca. 1 cub feet) that playes down to 100 Hz and is supported by 2 active subs."

Is that the best they could do? I thought I was going nuts with a 10" Wharfedale in 0.8 cub ft AP. It went lower than 100, more like 50. Didn't measure it, I was over sign waves by then.

But that is too much speaker for 1 cub ft. At least 2. Such a tight enclosure kills the upper bass / lower mids clarity and attack.

It's a bit more work in the enclosure - an Onken.

Regards,
Geoff.

[happy.gringo]

The Germans measured the Qts at about 30% higher than the published specs. Which one do you think is correct?

[badman]

A 10" like this might do well as a mid/tweet on an open baffle- highpass it above the f3 of the dipole rolloff (400Hzish?), and have woofers underneath that.

That should keep the excursion limited sufficiently to get good SPLs, and the woofers will become more the limiting factor, in most cases.

You could of course add XO and a tweet.

I don't think you would need to use crossovers that are particularly complicated- the rising response gives an improvement in power response, isn't too dramatic, and doesn't show any wild breakup modes. Obviously the driver is in breakup mode, you can see the ripples on the impedance plot, but it's not misbehaving too badly in terms of frequency response.

[Rudolf]

Originally posted by happy.gringo
The Germans measured the Qts at about 30% higher than the published specs. Which one do you think is correct?

That Qts=0.411 is the average of 2 drivers measured, and they differed by +/-3.6%. So it does not seem to be an outlier. And if you look at the link provided by lovechild - these guys are in the know. I would trust them more than the salesmens specs.

[Geoff H]

Rudolf, surely you can't be suggesting the sales people tell little fibbies. But yes, take heed of third party results. I did read somewhere these have a bit of spread in the specs, that's why they're sold in matched pairs.

Let's not confuse things hear. James did say he's new at this, and want's to get his up and running behind his SET, as a full range. So lets avoid crossovers and/or bi-amping.

One thing we've overlooked is his question "would it be worth placing the driver in an "asymetrical" location in the front baffle?"

Put it this way, it wont hurt. Just offsetting the driver 30 or 40mm will reduce baffle step issues.

James, how wide is your listening room? And how are your woodworking skills, tools etc? I have an idea.

Geoff.

edit: spelling a bit sad 1st thing in the morning - more caffeine.

[knightsound]

Geoff, thank you for your feedback re. using a wider front baffle and an asymmetric driver location. My listening room is 4670mm wide x 4980mm long x 2620mm ceiling height. The floor area is hard although I intend to install a thick wool carpet across the majority. My woodworking skills are better than my technical drawing skills but I´ll probably get a local carpenter to build the cabinets as my tools are in the UK. What´s your idea?

Lovechild, that German analysis is very detailed! While I think I understood some of the information, and the modelling re. on-axis/off-axis radiation, the comments at the bottom of the page relating to the ¨entzerren¨ (cross-over?) I can´t follow, ¨ oder unterhalb von 1 kHz z.B. einen zweiten 10" SUPER spendieren, womit man dann eine 100 dB/2.83V/m 4-Ohm-Box hat!¨ Are they suggesting running two drivers in one cabinet?

Badman, on cross-overs I´d like to avoid them if possible, and not only because bi-amplification using 300B´s would be too expensive for me!

KR,

James