Zu introduces Soul 6


Major changes:
1. $5999 starting price
2. Okoume standard finish instead of hickory
3. Bigger cabinet - up from 31.5" to 36"
4. 120 days to audition in home!

Zu claims Druid 6-type performance, deeper bass than mk.II, more amp friendly, horn-like impulse response.
I am intrigued.  Soul Supreme is a nice value at $4500 so Zu must really feel this a step up in performance to price it above that.  

I wonder what the fate of the Soul Supreme will be. As in will they keep developing it or will the Soul line be rationalized to the Soul 6 alone. I had the Superflies and currently have the Supremes. 
The Soul 6 is more expensive than the Soul Supreme so it will be interesting how it sorts itself out. Zu prices lately have been going up and not slightly. Makes me wander if these increased prices to make up for so many Dirt Weekend Omens sold.
I like Zu Audio speakers a lot, but have not heard these. A bit skeptical of the specs without the tweeter, but I only have very limited exposure, Omen Def and Soul Supreme.  I'd also be interested in hearing reviews.
It has a supertweeter. The supertweeter is concentric in Soul 6, like in Cube. The largest advance is due to the completely redesigned cabinet. Okoume is both lighter and stiffer than the materials used in all prior Soul speakers. This allows an extensive revision to the internal bracing scheme, and a more complete implementation of the Griewe room acoustic impedance matching, for the Soul cabinet configuration. Okoume is also a primary driver on the cost difference over current Soul Supreme, including both the material and the increased labor to work it. Resonance control & energy management. in the entire system is better than Soul Supreme. I expect to like it.

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Zu has been slow getting them rolled out due to supply issues.  There are a couple of people on the Zu owners facebook group who have them and say they are the real deal. 
I'm going to order a pair once they get the supply issues resolved. If anyone receives a pair I would love to hear your review, thanks.
I'm guessing no one has heard the new Zu Soul 6's on this forum yet? I got an email from them and they are saying delivery in 6 weeks. Hope that is true.
I enjoyed my Soul Supremes except for the poor integration of the full range driver and the super tweeter. I'm curious if this coaxial design solves that issue.
I should clarify my original post, it was taken from Zu's site on the day Soul 6 was released. 
Some corrections/additions:

Cabinet is the same size as Soul mk.II: 31.5 inches
Entire cabinet structure is Okoume, not veneered fiberboard
Bass extension down to 38 hz

I have to say of the 5 Zu models I have heard in my home, Soul mk.II was my least favorite.  If Sean is able to get Druid type performance out of that cabinet, he truly is a genius.

John Darko currently has a pair of Soul 6 in his room, hopefully he will be posting a review soon.

I have a pair of Soul 6 arriving on Wednesday. I have Druid 6 and Definition 4 to compare it to. I'll post comments in a week or so.

get one pair . second is free

15% off today,, I just cked the speaker looks and  the db spec,, all it is , some sort of WBer /whizzzer, cone looks paper, I don't like paperpaper, Only bamboo paper/bamboo wood types. They dont say what the cone is made of,, I NEED to know. 
I only like treated bamboo fiber/pulps/wood ofrmashed banana pulp (Tang Band). 

OK now we got that out the way..onto db sens
wow a  wopping 100db. 
Thats 6 db more than my limit, 
Yeah I know my DavidLouis VX8 is in fact 95db, thats 1 db more than my allowed max.
'WEll let me say 94/95db sens is ultimate limit.
There is going to be serioes issues witha  95+ db sens WBer in my system. 
My amp boasts 100 watts. Rm is small, very  near field listening.
= 96+db not doable.
Folks need to be aware when making  speaker choices.
You have to know certain things abouta  speaker before  hitting the  BUY NOW button.
The speaker may indeed be a  steallar stunning voice.
But again the db sens is 4db over my limit.
WE need to open discussion  about db sen s, how edach 1 db increment decides how a  speaker will perform in certain amps/linestage.
Most if not all linestage have a  good bit of gain this higher amplification drives the gain factor in the amplifier this creating high gain  in the speaker circuit. Thus making any db sens over 96db a  serious issue in most home settings. 
The benifits of a  12AX7 gain in the linestage delivers superior dynamics and details. 
There are tradeoffs. Which is why i imagine some linestages employ a  12AT7 or 6SN7 type tubes.  Lower amplificatio facots. 
I prefer the 12AX in drive tubes  with AU's softening the initial gain. 
Both together work their magic. 
But you pay with higher gains.
Trade off tradeoff tradeoffs.
Everything in audio has some tradeoffs. 
Most of AER/Voxativ speakers also are disqualified from my interest due to  high db sens. 
With any speaker at 96db+ I would need a  20x20x12 room to make the speaker work also a  true flea watt SET/ 1-4 watts.

Most systems have too much total gain, and this is independent of amplifier power. If you have separate preamp and power amp, the input sensitivity of the power amp and the output voltage of the preamp have to be considered to get useful range out of the volume control. You could have a 2w amp with an input sensitivity of 0.5v paired to a preamp with 10v out and find the system very annoying to use. On the other hand, you could have a 200/200w power amp with an input sensitivity of 3.5v combined with a preamp with 2.5v out and find that the preamp runs out of drive before the power amp can be driven to full power.

You can also find 12ax7 preamp circuits that have relatively low total gain. Many high efficiency speakers have low or only modest power handling. Zu speakers combine high efficiency with high power handling so large amplifiers aren't a problem, but they aren't necessary either.

There are other ways to solve this problem. One is to use a TVC or AVC for the linestage, so that you maintain the drive in the system without adding gain, or only a little (+6db). If for other reasons of your own you choose to combine a high gain preamp with a high gain power amp, you can use high quality attenuators between the two. Or you can choose a modest-gain active preamp (~10db - 12db) with a moderate-gain power amp (~22db) and have a usable system regardless of power level.

The cone of the Zu Soul 6 main driver is wood pulp (paper) based treated with nano materials. As Zu explains it, "...The driver’s cone is a paper pulp substrate, processed with a liquid solid matrix utilizing several nanoengineered materials. Some key components and compounds include: nanosphere ceramics, synthetic epoxy, cristobalite, plus the use of amorphous fumed silica and aircraft dope. The nano materials and application process reduce weight and increase strength and propagation velocity without incurring any sacrifices in damping..."

The nano materials and the carrier evolve as Zu drivers evolve. Like all Zu main drivers, the new Soul 6 driver (including the whizzer) covers the range of 35 Hz - 12kHz, with the range above 12kHz handled by a supertweeter on a high pass filter. In the Soul 6, the supertweeter is mounted concentrically in the center structure of the full range driver.

This is not a simple paper cone driver. It retains the tone and texture of paper, with the lightness, strength, stiffness of synthetic and metal cone materials that otherwise don't sound as good. The concentric driver behaves as a point source, and the okoume ply cabinet is as critical to the vivid, lifelike sound of Soul 6 as the latest main driver is.

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Speaker not 15% off. Learn read and use proper paragraph before post even better write in notebook and keep on shelf. I have old essence in wood shed system use 3 watt line magnet amp sound nice. neighbor wife like when I split wood she always coming over offer refreshment and sometime like to strip down to use pool. Maybe I replace old speaker with these.
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4. 120 days to audition in home!

In 5 minutes or LESS I;'ll know if a  speaker is for me,, If its a borderline case, then yeah 30 minutes. 
1st you have to know how a  neutral speaker sounds, aka Seas Thors, 
Then you have a  reference point. 
Otherwise its like being lost in a  desert.

In 120 days you can get use to anything.

If it takes more than,, say 30 minutes to figure a  speakers voicing with your own test cds then he/she should not be buying any speaker.'As they are too green and need more time to develope speaker lsitening.
What opened my world to hearing how a speaker should sound began with the Philips 475 High Fidelity  next Seas Thor next highend WBers.
All reference speakers
Not getting to listen for 120 days, but to compare to what I have in new listening room.😷 Starts with M and ends with C, 9 letters. And that's Wheezer cones according to oldhvy...

Steve Guttenberg aka the “Audiophiliac” has a new review out today on YouTube. Sort of surprising to me though I’ve never heard a Zu Speaker. Short version: it’s a mixed bag. Lively, great imaging, engaging, but he worked hard to get a tonal balance he could live with (not enough bass without some fussing).

I’ve actually been considering both the Zu Soul 6 and the Klipsch Cornwall iv so his comparison between the two is helpful. I’m interested to hear others’ reactions to this new bit of data.

I almost went for these but didn't want to deal with the supply chain uncertainty. Based on this review I'm glad I passed for now.
The thing I would add is that after listening to many products that Steve and other guys reviewed- the reviews tend to be an arrow aimed in a certain direction. Once you take into account the room, gear, tastes, personal abilities, language skills, breadth of knowledge, etc, things can change some. 
The Cornwall is fun. Not the best in clarity or depth of stage, but big and powerful with nice tone and less brightness than I expected. They had mids that I coud live with, unlike what he's saying about these 6's, but that's just me.  

Srajan has an ongoing preview that will become a review over at 6moons. He's owned a few models and always stays in touch with Sean and the guys at Zu.

All the best,
I gave up trying to read those six moons  reviews years ago. I couldn’t wade through all the verbiage. 
I've learned to skim thru his prose but concentrate on his technical explanations which he excels at. He's also the rare reviewer who'll put any piece of gear he has thru as many system permutations before settling on his decision.

As for the Zu piece, there are some lengthy explanations from Sean himself that are a treat to read. He's different than John DeVore but it's nice to listen to their philosophy and background when they have a chance to expand on it.

All the best,
I don't understand the love for Zu. Every time I hear their speakers at a show, it is one of the worst rooms. Constantly. Confounding as they often use Pass amplification. They do create a cool atmosphere though.

Maybe they make good speakers and just don't know how to set them up and drive them properly without distortion. Who knows?

Long story short; anyone planning a Zu purchase should first have a proper audition with their amplification.
Just an intermediate note here, prompted by Steve Guttenberg's evaluation on Youtube. There are some descriptive inaccuracies and setup errors, and one inadvertent error by Zu at the outset.

First, he has difficulty explaining the Soul 6 design. He refers to the supertweeter being "crossed over" and then tries to explain that the speaker doesn't have a crossover. If Steve simply and correctly noted that the supertweeter is on a high-pass filter, that whole word salad could have been avoided. He also refers to Soul 6 as a "bass reflex" design, mischaracterizing the Griewe driver-to-room acoustic impedance matching scheme.

It goes wrong in some vital ways from there, but Guttenberg does get the immediacy, speed, articulation, dynamic slam and tone factors. 

I am listening to a pair of Soul 6 right now. Steve says he couldn't get satisfactory bass from his pair at the more open end of his room, claiming roll-off at 57 Hz. Not me. Even before I got into making setup adjustments, just plopped on bare floor right out of the shipping cartons, Soul 6 showed solid 35Hz bass where present in music, and useful, audible response of 32Hz content in a relatively unbounded room, verified with 1/3rd octave visualization. Further tuning of the Griewe gap to the floor improved bass response and quality further. Why was real bass easy for me and elusive for him? Hard to tell through a procedurally-light video commentary.

Guttenberg then claims the speaker sounded best if he sat on the floor, complaining of tonal shelving at his seated height. So in an effort to fix that he and a buddy got the idea to tilt back the speaker, using long spikes on the front and the stub bolts on the back. Well, now the Griewe scheme can't work quite correctly and it influences the FRD well into the midrange.

I'll post complete comments on this speaker after I put them through some further violence to complete the break-in process Zu started. I think Zu erred by shipping Steve's Soul 6 pair too soon, and mine too. Their standard 2 weeks continuous burn-in turns out not to be sufficient for this new concentric driver, and stopping there leaves a narrow-band midrange stridency that gets wrung out by doubling the burn-in regimen on Zu's rack. A week in, the resulting glare is receding for me but it's taking extra effort to apply the necessary abuse. Hence Zu is going to require 4 weeks of break-in at the plant before delivering Soul 6. Druid 6 was very much the same way initially. Zu did 2 weeks of burn-in on their rig, then it took another nine months for my pair to fully stabilize. Zu shipped Steve's speakers too soon. Steve shot and posted his review too soon. Until the new-cone stridency is wrung out, the speaker will sound too forward on lots of modern recordings.

To a Druid or Definition listener, the Soul 6 acoustic focal plane will be perceived as lower than those speakers that have FRD output above ear level, but again as the speaker opens up during break-in, that focal plane drifts higher. On my couch, my ear height, seated, is about 39" off the floor. The Soul 6 floor to centerpoint of the concentric FRD is about 27". But after the first 3 days, TV and cinema dialog accurately attached to visuals on a 60" display mounted with vertical center at 44". The speaker scales well spatially and dynamically. Depth is not lacking. Right now I have the Souls 10 feet apart and the center still holds. Dispersion in all directions is better than for any single-driver Zu speaker to date.

But you have to get a complete break-in on them, respect the Griewe gap, and preferably not choose an overdamped amp. So far I've been listening to custom tube amps 10w - 18w (p-p triode, single-ended pentode), and 180w M2tech Crosby monoblocks (meting out the flogging). My experience is that all of the Zu concentric tweeter speakers demand more careful amp selection than the non-concentric tweeter models, even going back to the original Zu Cube. Soul 6 is no exception. More later.

Zu shipped Steve's speakers too soon. Steve shot and posted his review too soon. 

That sounds right to me. Thanks for the detailed write up. 
One of the things I like about Guttenberg is his ‘everyman’ approach. But in this case that might have backfired a bit. 
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I see this video and the ink maybe this guy drop too much acid or his shirt too loud to hear what going on. Now fan club enter in adhoc all reason why this guy that have two hundred thousand viewed goofed review. This guy good guy with balls get up and do what he do with those clothes on. time will tell but sound like they make mistake with design unless none of that important we all like different thing.
The design is sound, and highly considered. Like anything, it just has to be used correctly. If it is, then what people like comes into play. -Phil
The Soul 6 arrived today, and we fully agree with 213cobra. These are surprisingly good right out of the box on the stubs without fussing.  It looks like Zu gave them maybe 2 and a half weeks or so of burn-in.

No one here is going to buy in to these comments, Trust me, 
**burn in,,** right out the box,,,,we know how to translate this to mean other things...
**surprisngly good...**

Mozartman, I usual no agree with much you say but this guy review the speaker and give impression. It not like they tell him play it for 1 year before review. He gave opinion on lots of they speaker and nobody raise hand and say no no. Now they say all his good feedback good but all bad no good? This what you saying too? You self proclaim single speaker expert what you take?
Incomprehensible. Always a riddle wrapped in a mystery inside an enigma. OK, Churchill said that, but it applies here.

I'm waffling between Soul Supreme's and Soul 6s for my small listening room (12x13).  Had Druid IVs about 10 years ago and loved the dynamic sound but size was just too big for my room and maybe wrong amp at the time. 

I found the Guttenberg review of the Soul 6 confusing - down side of youtube reviews which seem more about entertaining than written versions.
Looking forward to both customer experiences and professional reviews of this speaker.  But am also leaning towards the Soul Supreme at this point which seems to capture more of the Druid sound in a smaller package.

Soul Supreme compacts Druid 5. Soul 6 compacts the sound of Druid 6. with the newer concentric driver. Druid 5 was a relaxed, easygoing, amp-tolerant speaker, more open and elastic than Druid 4. Druid 6 is strikingly more vivid, energetic, revealing and requires more thought about the gear train that comes before it, particularly the amplification. Soul Supreme and Soul 6 have a corresponding relationship.

One would expect a $6000 (Soul 6) speaker to both be more vivid and revealing than a $3800 (Soul Supreme now) one, and so it is. That difference is an opportunity but it also means that while both can work well in your room, Soul Supreme is less likely to prompt one or more changes in associated gear when plopped into an existing system.




thanks for this comparison Phil - what I gathered from various threads but your comments should be of value for lots of people wondering about the two speakers. 

I ended up taking advantage of good Zu pricing to order a pair of Soul Supremes which I think will work nice in my smallish room.

My current speakers are Harbeth 30.1s so based upon my 10 years ago Druid experience is going to be very different presentation.  Have a big Hegel 390 amp - so for first while will have to mate with the Supremes as well although I have also read some prefer big power with their Zu's.

Look forward to reading more about Soul 6 as more comments (and reviews) come in.


Zu speakers don't need high power but they can benefit from it on some music if the amp doesn't give up too much qualitatively to deliver power. I usually listen to 10-18w single-ended pentode and push-pull triode or pentode amplification on both my Zu systems, but keep a pair of solid state monoblocks around (~270w into 6 ohm Def4; 90w into 16 ohm Druid6) for certain uncorked experiences. Of all the Zu speakers, the Soul Supreme will certainly be a different presentation than your Harbeth, but also the Zu closest to it. Soul Supreme is a 16 ohms speaker so your Hegel 390 will see its power reduced to ~125/125w, a considerable cut since the Harbeth is a 6 ohms speaker, raising your amp's potential output to about 375/375w into that load. Still more than you need for Zu but less overkill. You may find it sounds a little cleaner into the Soul Supreme's higher impedance.

The Soul 6 pair I am listening to are nearly settled enough for commentary, so I'll post more in a week or so.


Really curious if anyone else has Soul 6 first impressions out there. Or @mozartfan @213cobra would love to read more of your thoughts on these. I have owned a pair of Zu DW's and a pair of Soul II's. Sold both a while ago when downgrading and have been living with a pair of Fritz Carreras running through a Leben 300xs. Very happy with that combo, but sometimes miss the vividness of my Soul's. 

I'm giving my pair of Soul 6 another week or 10 days to further settle in, then I will post complete comments, including some comparative notes relative to Soul Supreme, Druid 5, Druid 6 and Definition 4.


@ Avgon

well considering Zu offers a  very generous return policay, no restock feees only your FEDEX ship cost,,I'd say try them out.

For instance say you boughta  pair of Wilson;;s, return costs are staggering. 

+ lets say 1 goes back damaged due to excessive weight, thats another $500 off, so $400 ship + $500 for 1 nick on putside cabinet,,makies a  Wilson return simply impractical. 

Lets us all know how the Zu's sound