I will miss the discontinued Accuton's..

[fish fingers]

The expanding 'Cell' range means more Accuton drivers are being discontinued, which I think is a real shame.
I'm a big fan of the 2" midrange C50-8-044 and that looks to be getting the chop, so will have to purchase a few pairs quick! Personally think the anti resonant cut outs do a great job and look good too..

I've yet to see a decent review of a speaker using Cell's to be honest, and read a terrible review of the Coltrane 3

[5th element]

From the limited measurements I've seen of the Cell drivers they've performed pretty poorly and certainly nowhere close to how they should perform given their premium price.

The C50-8-044 is one of Accuton's gems and whilst I have not used it its measured performance is stellar and I would certainly like to.

[JonMarsh]

I have used a C50- it IS a very nice little part, but then, if the guys driving Accuton's volume don't use it, then someone has to make some business decisions, unfortunately...

I haven't personally tested any Cell drivers, just reviewed published data from Accuton, and so far haven't seen anything that grabbed me and said, "Hey, that's cool!" For instance, the AS-190-9-251... explain to me again why one of these would be better than 4 or 6 SW223BD02? It is trick looking, but the cone break up is 1,000 Hz lower... while the PDF claims a linear excursion of +/- 16mm, the Spec list says Xmax of 9mm.

But, never judge a book by it's cover... but these are likely too expensive for me to read...

[BobEllis]

Oh, come on Jon. The Cell drivers' open back just screams dipole. Isn't it time to revisit that concept in light if your current what goes around comes around project?

[Hdale85]

I think you mean projects* lol.

[5th element]

Jon always has projects 'plural' on the go

And crikey $1000 dollars for the AS190-9-251? I am sorry but nothing about that driver is worth $1000. Scan speak has their 22W/8857T-00 at 1/3 the price, the same amount of guaranteed xmax (Klippel confirmed) and a super stiff alu cone that goes through break up, as Jon said about the SW223, significantly higher too. None of Accuton's current bass drivers perform to a standard that Scans do (at least from what 3rd party measurements I've seen). Yes the AS190-9-251 probably has very good thermal capabilities but as far as I can remember no one has ever complained about their Scanspeaks failing from thermal overload.

And then just to be perverse how many RS225s can you purchase at the expense of one AS190? Sure it's only 8mm of xmax, but they similarly have very low distortion and a rigid cone and they cost $50-60...

I remember at one point Accuton singing the virtues of the Cell concept drivers as a way to combat the ever rising neodymium prices, yet the Cell drivers cost ridiculous amounts of mulah.

[JonMarsh]

Jon always has projects 'plural' on the go

And crikey $1000 dollars for the AS190-9-251? I am sorry but nothing about that driver is worth $1000. Scan speak has their 22W/8857T-00 at 1/3 the price, the same amount of guaranteed xmax (Klippel confirmed) and a super stiff alu cone that goes through break up, as Jon said about the SW223, significantly higher too. None of Accuton's current bass drivers perform to a standard that Scans do (at least from what 3rd party measurements I've seen). Yes the AS190-9-251 probably has very good thermal capabilities but as far as I can remember no one has ever complained about their Scanspeaks failing from thermal overload.

And then just to be perverse how many RS225s can you purchase at the expense of one AS190? Sure it's only 8mm of xmax, but they similarly have very low distortion and a rigid cone and they cost $50-60...

I remember at one point Accuton singing the virtues of the Cell concept drivers as a way to combat the ever rising neodymium prices, yet the Cell drivers cost ridiculous amounts of mulah.

+1

Geez, the forum bot says +1 is too short!

[DS-21]

I will miss the discontinued Accuton's..

And crikey $1000 dollars for the AS190-9-251? I am sorry but nothing about that driver is worth $1000. Scan speak has their 22W/8857T-00 at 1/3 the price, the same amount of guaranteed xmax (Klippel confirmed) and a super stiff alu cone that goes through break up, as Jon said about the SW223, significantly higher too. None of Accuton's current bass drivers perform to a standard that Scans do (at least from what 3rd party measurements I've seen). Yes the AS190-9-251 probably has very good thermal capabilities but as far as I can remember no one has ever complained about their Scanspeaks failing from thermal overload.

And then just to be perverse how many RS225s can you purchase at the expense of one AS190? Sure it's only 8mm of xmax, but they similarly have very low distortion and a rigid cone and they cost $50-60...

I remember at one point Accuton singing the virtues of the Cell concept drivers as a way to combat the ever rising neodymium prices, yet the Cell drivers cost ridiculous amounts of mulah.

To that I only have to add that the bubble-cone looks like an awfully attractive thousand-dollar target for children's fingers.

I'm sure it'll find a place in badly-designed but visually striking speakers for rich status seekers, but I don't see anything compelling over the Scan and Wavecor options for music lovers.

[BobEllis]

I know Jon always has tons of projects on his plate, but since he's done dipoles and is working this: http://www.htguide.com/forum/showthr...d-comes-around I thought it would be fun to poke a little.

[JonMarsh]

I know Jon always has tons of projects on his plate, but since he's done dipoles and is working this: http://www.htguide.com/forum/showthr...d-comes-around I thought it would be fun to poke a little.

Guilty as charged... which is why I think I'll be enjoying retirement some day quite a bit, unless I get all my ideas built by then... (not bloody likely...)

[TacoD]

Jon always has projects 'plural' on the go

And crikey $1000 dollars for the AS190-9-251? I am sorry but nothing about that driver is worth $1000. Scan speak has their 22W/8857T-00 at 1/3 the price, the same amount of guaranteed xmax (Klippel confirmed) and a super stiff alu cone that goes through break up, as Jon said about the SW223, significantly higher too. None of Accuton's current bass drivers perform to a standard that Scans do (at least from what 3rd party measurements I've seen). Yes the AS190-9-251 probably has very good thermal capabilities but as far as I can remember no one has ever complained about their Scanspeaks failing from thermal overload.

And then just to be perverse how many RS225s can you purchase at the expense of one AS190? Sure it's only 8mm of xmax, but they similarly have very low distortion and a rigid cone and they cost $50-60...

I remember at one point Accuton singing the virtues of the Cell concept drivers as a way to combat the ever rising neodymium prices, yet the Cell drivers cost ridiculous amounts of mulah.

plus two

[Face]

It's about time they lower their prices too...a little bit at least: http://www.intemag.com/uploads/Rare%...20Bulletin.pdf

[5th element]

Wow the price has come right back down now.

[5th element]

To that I only have to add that the bubble-cone looks like an awfully attractive thousand-dollar target for children's fingers.

I would be tempted to try out how sturdy they are myself...:g>

It would be my guess though that it's fairly tough. So far Accuton have covered up all of their ceramic coned drivers with grilles specifically because they are so fragile, this one has none and it's just the right shape to accidentally end up getting kicked if floor mounted, or pressed by mistake by roaming hands. I know the Ultimax series have cones so strong you can whack them with metallic objects and they come away unscathed. Whatever laminate they are using for the cone, it could be pretty robust.

[Bukem]

I am currently contemplating mating the Accuton C90 cell midrange with two of their sandwich cone woofers S220-6-221, in a wide baffle 3,5 way topped off with a Scan BE. I'd probably run the woofers up to 250 and 450Hz after passing on duties to the C90. The BE would then be crossed relatively low at around 1600Hz. All DSP.

I have been following the Ardent project(s) with much interest. I would certainly agree not all Cell drivers are great performers but the comments above made me think wether the C90 Cell & S220 are up to scratch. I have looked at the C50 extensively but again and again the issue remains that I need to cross higher than I would like, driver positioning & nulls become an issue then as well.

It seems the Wavecor driver is sparking some interest.

Rgds,

Richard

[5th element]

Personally speaking I would give the Cell drivers a miss. You can see measurements of some (maybe just one?) of them here.

http://www.audiogurman.com/2.htm#c90-6-724

Compare it to others and it's not anywhere near as impressive.

If you wanted to use a stiff, ceramic type driver, without the 'limitations' of the C50, then I'd recommend going with this.

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

It has exemplary performance from 300Hz up to 4kHz although you'd want to cross over a little lower than 4k to tame the distortion bumps further up. This wouldn't be an issue of course if you're going to cross over quite low with the Be dome anyway.

The S220 has also been measured there too.

http://www.audiogurman.com/3.htm#c220-6-221

And it's the same story once again, it's really not up to the standard of what you'd expect for the price. Here's a SEAS W22 for comparison. It is far cleaner in the bass.

http://www.audiogurman.com/3.htm#w22ex001

With the new 8" from SB acoustics doing significantly better too.

http://www.audiogurman.com/3.htm#sb23nacs45-8

It's almost sad for Accuton because you can buy 4 of the SB23s drivers for the price of one S220 with the SB23s being much better drivers.

If you wanted to go the route of the C50 then this could be made to work.

Given that the 6640 can cross over pretty much as low as you'd like, this would give you a lot of flexibility for the upper xover if you were to use the C50. Certainly the upper range would be sorted nicely (Get them a close C2C with a 3kHz xover and you'd be set), but the C50 really deserves a 800Hz lower xover. The S220 is not at its best going up that high, but the SB23 or the W22 can easily reach that high without any issue whatsoever, the only trouble would be the C2C spacing.

If this was a generic three way with the bass driver mounted directly under the mid range (as close together as they could go), then in this case the C50 and 8" bass would be absolutely fine with the 800Hz xover. The trouble in this case is that the second of the two bass drivers sits rather more below the first bass unit. What you could do in this case is make the loudspeaker a 3.5 way. This would roll off the lower of the two bass units much sooner than the first and reduce any interference that would spoil the off axis. Even though you want this to be an active, DSP based, system, I would go the passive route for the .5 woofer. This would only require one inductor in series with the driver and nothing more.

If you go the Eton route, or any other driver with the ability to cross over lower, then I would recommend floor mounting the bass driver. This simply means placing the bass driver at the bottom of the front baffle. If you do this then you gain several things. The first is that the mass of the bass unit sits low down and helps add stability to the cabinet.

The second is that floor bounce typically occurs below 300Hz. If you place the bass driver on the floor then it is immune to floor bounce. The midrange driver will still experience floor bounce, but if you cross over at around 300Hz, then you do not experience floor bounce from the mid and as the floor bounce immune woofer takes over below there, you effectively eliminate floor bounce from your design.

The third benefit is that the floor mounted woofer sees the floor as an effective extension of its baffle and it is now immune to baffle step. The usual 6dB loss that you'd experience with a woofer off the floor simply does not happen. For three ways, paired woofers are common because you need the 6dB increase to compensate for baffle step losses, with the woofer on the floor this is not necessary so only a single driver is needed. I know you were going to go fully active, so sensitivity mismatches are made a moot point, but going this route is still helpful even here. If you would still want to use a pair of bass drivers then I would recommend going push/pull and mounting the second bass driver on the back of the cabinet, but close to the floor, with its magnet pointing outwards. The push pull arrangement helps in cancelling out even order non linearities associated with the non symmetrical part of the drivers stroke.

Still that was quite a lot of an explanation when all you were after was some driver advice, but the bottom line is, in my opinion and the results of the third party testing, that you are better off avoiding the Cell midrange and the S220 bass drivers. There are better performers, offering similar characteristics, for less money. Another bass driver option would be the 8" metal cone revelator drivers from scan speak. If you want bass drivers that could be used for a proof of concept before moving onto spending scanspeak type money then the Dayton RS225s would get you 90% of the way there too.

[Face]

Throw the 6640 in a waveguide and use the C173-6-090 instead. I'm not impressed by any of Accutons ferrite drivers.

[JonMarsh]

Throw the 6640 in a waveguide and use the C173-6-090 instead. I'm not impressed by any of Accutons ferrite drivers.

Hard to disagree with that, being a fan of the C173-6-90- I've tested other versions of 7" drivers for friends who didn't want to pony up the bucks for the big guy, and found them disappointing. However, the C79 has it's merits if applied properly, and has a different value proposition.

Matt, I've experimented with different heights and woofer vs midrange height and my recollection is I've had trouble getting the results I desired with a floor mounted woofer (early testing with Modula Xtreme)- but I'm going to give that one more whirl, see what happens, with my test cabinets, because the crossover frequencies just happen to be set right for your logic. If I have results I don't understand, I'll check back with you on that... :W

Made some progress setting up the simulation configuration for the Piranha's today, both 100W and 200W versions, AND built the test woofer crossover and most of the midrange crossover- plus got some real chores done, too, including on the GTS1000. was a pretty good busy weekend....

[Bukem]

Thanks to all for providing such extensive feedback. I was specifically referring to the S version of the Accuton 220 - that is to say the one with the sandwich cone.

http://www.accuton.de/drivers/detail.php?driver=29&matID=2&appID=4

The C90 does have some back wave issues which need to be addressed. Measurements after having addressed this issue can be found here (bottom of page):

https://www.hifi-selbstbau.de/datenbler-mainmenu-40/tiefmittelt-mainmenu-58/463-accuton-c90-6-724-abonnenten

[fish fingers]

I love the idea behind the cell drivers (literally) and you've probably chosen the cream of the crop as far as bling factor goes.
maybe wait until the new Carbon Rohacell SB drivers are launched, I'm hoping they will tick all the boxes.

[5th element]

Throw the 6640 in a waveguide and use the C173-6-090 instead. I'm not impressed by any of Accutons ferrite drivers.

That I am not going to argue with and would be the best choice imo.

Hard to disagree with that, being a fan of the C173-6-90- I've tested other versions of 7" drivers for friends who didn't want to pony up the bucks for the big guy, and found them disappointing. However, the C79 has it's merits if applied properly, and has a different value proposition.

The C173-6-90 imo is the definitive Accuton driver and should be what all of their drivers are modelled off. Most of Accutons drivers have lack lustre motors that are beaten by a lot of the competition be they less or more expensive. Their tweeters and small mid domes are a different thing entirely, but it's as Face says, their neo stuff generally performs much better than their ferrite stuff. This could be because of the underhung motor geometry that they adopt when going with neo.

Matt, I've experimented with different heights and woofer vs midrange height and my recollection is I've had trouble getting the results I desired with a floor mounted woofer (early testing with Modula Xtreme)- but I'm going to give that one more whirl, see what happens, with my test cabinets, because the crossover frequencies just happen to be set right for your logic. If I have results I don't understand, I'll check back with you on that... :W

Well the only problem is that for proper summation you need to sit a couple of meters away from the speakers and make sure that the driver C2C doesn't get too big for the xover frequency used. 300Hz has a wavelegnth of 1.14 meters, I'd want to keep the C2C between 80-100cm.

With my floor mounted system I do use it for nearfield stuff too and it works surprisingly well there too.

Thanks to all for providing such extensive feedback. I was specifically referring to the S version of the Accuton 220 - that is to say the one with the sandwich cone.

http://www.accuton.de/drivers/detail.php?driver=29&matID=2&appID=4

Ah yes! The S220 instead of the C220, brain fart. It still uses a ferrite motor system though and I don't expect it to perform any better than the C220 that I linked to before. The S280-6-282 on that site performs a damn site better, so yeah the neo underhung Accuton motors are a much better deal. Still not as good as the W22 SEAS though.

The C90 does have some back wave issues which need to be addressed. Measurements after having addressed this issue can be found here (bottom of page):
https://www.hifi-selbstbau.de/datenb...724-abonnenten

I figured it would have, that tunnel at the rear of the driver just screams resonant cavity, looks like my assumptions weren't wrong on that.

[Bukem]

Throw the 6640 in a waveguide and use the C173-6-090 instead. I'm not impressed by any of Accutons ferrite drivers.

What is your reasoning for using a waveguide in this specific instance? Directivity? Lower X-over?

[JonMarsh]

I'm not Face, but as I endorsed that idea, let me say I'm not just about talk in discussing the concept...



Reasons would be directivity control and dispersion enhancement, and reduction of distortion, and perhaps a little more flexility about crossover point. It also allows for a considerable measure of time alignment for crossovers that require that to work optimally.

This version was executed with a Duelund crossover; last time I used that, before going back to the quasi LR3 concept I've used in the original Modula, the NatalieP, the Isiris, and the Wavecor Ardent - which, for the record, require a time offset for phase summing that falls nicely in the range of typical driver offsets when all mounted on the same front panel....

[Bukem]

Wow Jon, impressive stuff. Are those 26W's?

[Face]

Wow Jon, impressive stuff. Are those 26W's?

I'm not Jon, but yes those are SS 26W in 12ohm.

[fish fingers]

And can I be Frank, they look stunning

[Bukem]

Quite stunning, I must agree. Given the recent Ardent developments the 1$M question then becomes Wavecor or Scanspeak? It also crossed my mind to use a both the 26W and 22W in a single sealed volume.

[fish fingers]

Interesting reading about the difference between the ferrite and neo motors. What about this 6" driver, anyone used it? Its the one ferrite driver they do which does seem to get fairly good feedback

http://www.accuton.de/drivers/detail.php?driver=37&matID=4&appID=3

[JonMarsh]

well, it looks better than the 096 and some others- but the way Accuton presents distortion with a linear plot obscures differences in the lower level stuff, down around 0.2 to 0.1%, I much prefer a dB presentation. If I recall correctly, this is the 5.5" Accuton driver used by Selah Audio in an MTM they showed at CES a number of years ago (it could have been RMAF- but my recollection is CES, one of the last times I attended)

And if you look at this critically, it is in a completely different price class than the 173-6-90, so quibbling about the difference in nonlinear distortion hardly seems fair. But the way they present the data with a linear scale tends to unreasonably minimize that. Whatever one says about the importance or lack of importance in nonlinear distortion, it's impact, especially when coupled with resonance amplification, is undeniable in my experience with both direct comparisons and long term listening.


This doesn't seem too bad at all...




Unless you're used to listening to this...



Keeping in mind a 2500 Hz -6dB crossover point in both cases... let's just not talk about the 3:1 difference in price!

And for certain, it's much better than this: