Anyone used Illuminator 12MU's ?

[fish fingers]

Looking for any feedback on these little mid's before I pull the trigger;
considering them for a high WAF 3-way build.
Thanks

[BobEllis]

I believe that's what Renron used in his mid price Ardent build. He's very happy with them. Jon heard Ron's build and said they give up very little to the Accuton C79. You should be happy.

[fish fingers]

Thanks! Good to know. I'd read some not so great reviews on the 15W illuminator.
Planning to use it with the SB carbon cone woofers, not sure if to go series (8ohm) or parallel to bring the sensitivity up to help match to a ribbon

[cochinada]

http://www.audiocomponents.nl/download/scan-speak/12MU-8731T00%20-%20Hobby%20HiFi%202013-1.pdf

http://www.audiocomponents.nl/scan-speak-driver-reviews.html

[Steve Manning]

I have the 18W in my 1071's and I'm very happy with the way they sound. Though I could not tell you how they compare to their smaller siblings.

[Zvu]

SBacoustics NAC, NRXC, MFC and CRC shares the same basket and motors. Only thing that's different is membrane materials (and spider sometimes). On www.audiogurman.com there are extensive measurements of distortion for SB17NRXC35-4, and what is more important (since you will be using CRC for low end) there are distortion measurements under 100Hz (well for 17NRXC35-4 at least). Below 80Hz distortion raises rapidly for 17NRXC and i suspect that is the case with all of the 6.5" from SB series (Satori 6.5" being different beast altogether).

For bass duties i'd look at Dayton RS180-4, Seas L18RNX/P, Seas P18RNX/P or even Seas L16RNX.

[fish fingers]

Thanks everyone. Zvu cheers for link, most measurements don't go down that low. Still considering the SB's as they are available not far from me- another option was ES180ti (sold out).
Not sure 2 RS180 per side will have enough xmax for my music tastes but will read up. RS225 cabs too big. Will check out the Seas woven cones, maybe available a shop in town.
Much of the outlay is going towards the mids(which in my mind makes sense).. less budget for woofers.

[Zvu]

Thanks everyone. Zvu cheers for link, most measurements don't go down that low. Still considering the SB's as they are available not far from me- another option was ES180ti (sold out).
Not sure 2 RS180 per side will have enough xmax for my music tastes but will read up. RS225 cabs too big. Will check out the Seas woven cones, maybe available a shop in town.
Much of the outlay is going towards the mids(which in my mind makes sense).. less budget for woofers.

RS180 has Xmax of +/-6mm and SB17CRC has Xmax +/-5.5mm (linear coil travel peak to peak is 11mm) so RS180 is a bit better in that regard.

If serious loudness levels are required, i'd try with one or two SB23MFCL45-4 per side. 8" woofer almost doubles effective cone surface of one 6.5" woofer. You'd save volume and money buying one 8" instead of two 6.5".

http://www.dibirama.altervista.org/home-page/sub-woofer/312-sb-acoustics-sb23mfcl45-4-sub-woofer-8-4-ohm-300-wmax.html

I'd cross it at 200-300Hz with midrange. It does F3 at 35Hz in 20 liters enclosure with ease and with Xmax of +/-12mm (linear coil travel p-p is 24mm) you practically can not drive them too hard unless you are really trying to.

[fish fingers]

You're right, hadn't noticed the Xmax on the RS is better- little surprised by that. In the SB's favour they are vented through the magnet, the RS range isn't.
Another issue with the RS range is the parameters are all over the place. Some offer good extension, others offer good sensitivity, but not in the size or ohm rating you'd think! Quite hard to find a good match to the little SS.
I also found a shop selling Seas drivers, their curv cones are rather nice.

[Zvu]

No driver with phase plug will be vented through pole piece - it can't be. It's vented naturally through opening of the voice coil. That is rather good thing imo. Seas curv cone also has phase plug (as do every one of Excel series woofers), hence no pole piece venting.

[fish fingers]

Thanks Zvu for pointing these things out. I visited a local Seas distributor to see what they had in stock - sadly no curv range but they did have the 8.5" Nextel excel. Nice looking driver

[fish fingers]

Ok I'm changing the design - I was offered a good deal on Nextel drivers (8.5" and 4.5") - they will go with a pair of viawave tweeters I already own.

[Zvu]

Nextel 8.5" is a good idea. Nextel 4.5" - not so much:

Baffle size (WxH): 19×30,5cm with 12mm round-over on the baffle edges (r=12).
Driver position: Mounted on center-line with driver unit center 20,2cm from the top of the baffle.
Mic position: 1m distance, on mid-woofer-axis.
Smoothing: 1/24 octave smoothing applied.
0, 15 and 22.5 deg measurements...



And distortion plots 85dB and 95dB:

[fish fingers]

Yes I've seen that although I'm not altogether worried as the baffle size was influencing some of what was measured

[Zvu]

I'm not worried about baffle step. I'm worried about 5dB dip centered at 1.2KHz that is pretty wide and i'm worried about distortion. Although W12CY003 has overall low HD3 distortion at 90dB, it also has a peak in it that reaches 1% at 1KHz, where ear is quite sensitive. If Seas is the easiest for you to aquire, L12RCY/P would be cheaper and better choice imo. It has lower HD2 through entire usable range (500Hz-2000Hz). HD3, although a little higher than W12CY003, remains under 0.5-0.6% even at 95dB and reaches 1% only at 2KHz, and that determines xover point between midrange and tweeter. L12RCY/P has impedance plot without any ripples all the way up to breakup. There are lots of tweeters that have low distortion at 2KHz, including Viawave that you will be using.

[5th element]

Can you consider the Eton Symphony 4" midrange driver?

http://www.audiogurman.com/2.htm#eton3-400

This has superlative measured midrange performance and a stiff cone to boot. Its resonance is high up in frequency so the third order distortion peak only creeps in at just over a 4kHz. As a proof of concept driver you could give the RS125-8 a go. It's inexpensive and sounds fantastic.

The viawave should be a perfect match for it, crossing steeply (4th order acoustic) at 3-3.5kHz for a decent enough directivity match to its little waveguide.

I know people mention this all the time but your crossover skills are really going to be what makes this sound awesome or less so. Personally I dislike all of those softer cones that exhibit resonances that create dips in the FR and peaks in the HD between 500-2000Hz. This is exactly where you don't want issues. Still the peaks tend to only be in the 2nd harmonic which isn't that big of a concern.

Given the choice I'd always go for the stiff cone, without 500-2000Hz issues. But that's only if the tweeter is capable of handling the low crossover point, necessary for keeping the peak in the 3rd harmonic out of the way.

The RS125 isn't the best in this regard as it really needs a 2.5kHz xover for the best results. As you're using a ribbon, the usual rules apply as to 'must not cross over too low', so in this respect the RS125 would only be a poor proof of concept kind of thing. Given the above measurements of the viawave it'd be fine at 2.5kHz just not played too loudly.

The Eton is pretty great though, having no third order malevolencies until over 4kHz.

If you would rather go for a soft cone then that's up to you but all the soft cones tend to have that dip and associated distortion bump. Of the three big names with 4" drivers, you've got SEAS Excel range, Scanspeaks Illuminator (which is the best mid scan has made for a very long time imo) and then the various Satori drivers from SB. I would personally prefer to go with an MW13P or MR13P variant from SB. Same dip/bump as the others but with the best motor out of the lot. The SB will require some decent filter work as it has some peaky breakup, but none of this is present in the distortion.

[Audiophile100%]

Looking for any feedback on these little mid's before I pull the trigger;
considering them for a high WAF 3-way build.
Thanks

i suggest you : http://www.sbacoustics.com/index.php...4-sb12mnrx25-4
simply wonderfull and cost is very low: it can be battle against 12mu
more money don't give you always better results

[5th element]

i suggest you : http://www.sbacoustics.com/index.php...4-sb12mnrx25-4
simply wonderfull and cost is very low: it can be battle against 12mu
more money don't give you always better results

The little SB could have been amazing if SB Acoustics had added some copper into the motor. SB had included copper in the 6 and 5" drivers of this range, but for some reason neglected to include it in the 4" drivers. I do not understand why.

Here are the 5 and 6" drivers with the copper in the gap...



Note the flat and low levels of third harmonic.

Now for the 4"...

The third harmonic starts out low but then rises, this is the result of omitting the copper. Adding the copper isn't expensive, Vifa do it on their very cheap range of full range drivers. Why SB didn't include copper I don't know all it does is worsen performance and limit high frequency extension.

Not using copper in bass drivers sometimes make sense. As you can see with the little SB, low frequency third order is impressively low, so if you were to cross over no higher than around 300-500Hz you'd be fine.

Obviously the Scanspeak uses copper and has low third order. Compared to the other drivers with similarly flat third order the SB is not really that impressive. Some drivers with copper do exhibit a rise but the overall level of third order remains lower than if without. Compare the SEAS metal cone standard range to the Excel range.

[Audiophile100%]

you are wrong also the 4" has copper rings in the motor
all drivers from sb have copper ring

[Zvu]

If you are going to use 12MU, i'd recommend 8 ohm version. It is somewhat better in distortion than 4 ohm brother. Both measured by HobbyHifi:

https://s11.postimg.cc/41yzzk0pv/12_MU_izobli_enje.jpg

If you want same or better level of performance but cheaper, try to get your hands on Tang Band W4-1337SDF. HD2 and HD3 remains under 0.3% from 400Hz-3.5KHz at 95dB - not too shabby. Not to mention you can buy 4 of them for the price of one 12MU. Measurements by Klang&Ton:

https://s11.postimg.cc/8cdnv55sz/1337.jpg

It's kinda different beast from W4-1337SD measured by Zaph. It does have HD3 peak at 4.5 that correlates with breakup at 13.5KHz (That 1337SD/SA doesn't have) but it is low in level as is rest of the distortion that bothers the Nd version (Nd version has rise of HD2 from 500Hz to 1000Hz and a bit higher HD3 in the passband). I ordered 4 pieces for me but one of them has been destroyed before the shippment arrived - but that gave me the unique opportunity to look at the core and how it is made. Machined Al phaseplug is glued to the core - that can be bad thing (like you see on the pics) but the flux is a bit stronger because there is no hole through the pole peace. Copper sleeve is visible on the pics too as is underhung motor. Not too bad for the 55 bucks midrange. I've failed to find better midrange for twice the money (lower distortion, better CSD, more linear frequency response) - but for twice the money you can buy 2 of them and here we go again...

Sorry for blurry pics - my lens was dirty, and i didn't want to do it again, so here goes nothing:

https://s11.postimg.cc/5wbuhanqb/DSC_0041.jpg

https://s11.postimg.cc/8265bsr6r/DSC_0042.jpg

https://s11.postimg.cc/vho2h5axv/DSC_0044.jpg

https://s11.postimg.cc/ypsju6x7n/DSC_0045.jpg

https://s11.postimg.cc/8ivybz4bn/DSC_0046.jpg

Oh yeah... Nobody seem to remember ZA14W08... It costs 40 bucks, it is on par with 1337SDF - has to be xovered lower than TB though. Also cheaper from 12MU. Two W4-1337SDF's or ZA14W08's per side in MTM would demolish one 12MU per side in every possible way and for less money all other things being equal.

[Rick Craig]

You're right, hadn't noticed the Xmax on the RS is better- little surprised by that. In the SB's favour they are vented through the magnet, the RS range isn't.
Another issue with the RS range is the parameters are all over the place. Some offer good extension, others offer good sensitivity, but not in the size or ohm rating you'd think! Quite hard to find a good match to the little SS.
I also found a shop selling Seas drivers, their curv cones are rather nice.

The 12MU is a fine driver. You can't totally depend on x-max ratings because of motor and suspension limitations (ie, Klippel). The RS180 is a good example.

[5th element]

you are wrong also the 4" has copper rings in the motor
all drivers from sb have copper ring

No they don't and no, it does not.

Go read the product data on SBs website. SB always mention when shorting rings/copper/extended poles are used in their motors for enhanced linearity. The 4" models of the standard line do not include any of these! Copper isn't mentioned on the website and the measurements confirm it too.

[Audiophile100%]

ok, and why impedance raising of the sb 12m is very close to scan 12mu ?

[Matt M]

Take into account the different plot scalings. Compare the factor by how much the impedance rises from 500 to 10000. For sb12mnrx25-4 driver it is 3.3R to 10R (=> a factor of 3x). Same for the other SB12M drivers or the scan 12m/4631g00 (also no copper rings AFAIK). The 12mu/4731 is a different matter: the factor is 1.5x or less. Again, similar for the SB15 family.

[5th element]

ok, and why impedance raising of the sb 12m is very close to scan 12mu ?

It's very difficult to directly compare two drivers from their impedance plots just to tell whether they've got copper in the gap or not. While it is true that two otherwise identical drivers, one with copper and one without, will show lower inductance with the copper, the coil geometry and the overall motor matter significantly too.

Le(x) plots are far better for that but it's not the absolute level of inductance that's important but whether or not steps have been taken to reduce the linearity reducing magnetic fields that would otherwise be generated by the voice coil.