Mini-Method subwoofer... so far, VERY good!

Vinnie R. · « **on:** 21 Aug 2006, 02:06 am »

All,

I recently acquired a Zu Audio Mini-Method Subwoofer. You can see pics of it here:
http://www.zuaudio.com/mini_method.htm
It looks like Zu is still working on this new website, so there is not a whole lot of info about it on the site yet. I know it retails for $1500 and it uses two 10" paper cone drivers in a sealed enclosure. I think the plate amp is 100W RMS.

I am using it with my open-baffle speakers (single B200 driver per baffle) that are fed from the Signature 30 amplifier. I am using the volume controlled RCA outputs of the Signature 30 to feed the low-level inputs of the Mini-Method.

I’ve only been using the Mini-Method for about a week or so and I haven’t come close to putting in the burn-in time, but I can already tell that I am going to love it!

I’m really impressed by how well it seems to be blending with the OB speakers. It is very tight (it is sealed and uses two 10” paper-cone drivers), fast (it sure needs to be in order to keep up with the speed of those B200s in the OB), and has excellent tone… the bass seems to have very nice texture and character.

I’m in a fairly small room, so I don’t have the gain cranked up nor do I have the desire to do so. It doesn’t call out attention to itself. It integrates beautifully with the OBs. Right now I have the crossover set at around 50hz (adjustable from 40 to 160hz). I believe I read that the crossover is a slow roll off at 6dB per octave. This slow roll off seems to be the perfect match for my OBs, which begin to slowly roll off (6dB per octave?) in the 80Hz region.

I've read posts about adding bass with OB speakers (or with any speakers for that matter) and have been asked quite a few times about what subwoofers do I like. Well, I haven't really listened many that I can say that I like for music... until now. I'm very impressed how well this Mini-Method is working with my OB speakers.... a very nice surprise!

Zu did a nice job with this one and I'll be posting more about it once I get it all dialed into my system (as I find that perfect location in the room, knob settings, etc), but I just wanted to share my findings with you all.

Best regards,

Vinnie

JohninCR · « **Reply #1 on:** 21 Aug 2006, 04:45 am »

Hi Vinnie,

Can you adjust the sub from your listening position? In my room, I tried
many arrangements with different combinations of OB's, sub types, XO
points, etc. The result was the same using each arrangement of a mono
sub. The big open OB soundstage collapsed significantly down toward
the sub unless its volume was adjusted low enough to not be helpful.

mcgsxr · « **Reply #2 on:** 21 Aug 2006, 10:38 am »

Interesting piece - LOVE the design of that, the whole Industrial feel, with what I assume are strong Art Deco overtones.

Glad to hear it is working out well for you Vinnie!

Vinnie R. · « **Reply #3 on:** 21 Aug 2006, 12:28 pm »

Quote from: JohninCR on 21 Aug 2006, 04:45 am

Hi Vinnie,

Can you adjust the sub from your listening position? In my room, I tried
many arrangements with different combinations of OB's, sub types, XO
points, etc. The result was the same using each arrangement of a mono
sub. The big open OB soundstage collapsed significantly down toward
the sub unless its volume was adjusted low enough to not be helpful.

Hi Johnn,

I'm still getting a very BIG soundstage and the sub is only seems to be adding solid foundation to the music in a way that does not at all seem separated from the OBs. I don't have the gain set that high, but where it is set is still very helpful to the music. When I get a chance, I am going to play with locating the sub at different points in the room and see what happens.

Hi Mark,

Thanks! I love how it is not a big cube, but rather taller with a smaller footprint. The two 10" drivers are stacked on top of each other. They are light and fast paper cone drivers with a surround that is similar in appearance to the B200s ("acordian style").... as opposed to so many subs out there today with those thick rubber surrounds that need big watts to move them

They are a lot more like pro drivers. Whatever they are, they are doing their thang very well

Stempy · « **Reply #4 on:** 21 Aug 2006, 02:52 pm »

Mr. Vinnie,

2 appropriate positions for a single sub are directly between your speakers or a 2nd good option would be next to one of the two speakers.

I agree with you that keeping your foot off the volume pedal of the sub is a good approach and I'm doing similar things with my Method. Surprisingly I have tried the sub at various crossover points 50 to 150 hz. As long as you go at it with less overall output from the sub(Decreasing output as you go up the scale), things hold together fairly well. Haven't yet established a preference.

macrojack · « **Reply #5 on:** 23 Aug 2006, 08:03 pm »

It's fast because it was designed to keep up with the Druids. The 10 inch drivers in the Mini Method are the same ones that are in the Definition Pros and they are professional drivers.
I'm glad you like it, Vinnie. Between you and Zu, I've stopped looking at anybody else's amps or speakers.

Vinnie R. · « **Reply #6 on:** 24 Aug 2006, 02:47 pm »

Quote from: macrojack on 23 Aug 2006, 08:03 pm

It's fast because it was designed to keep up with the Druids. The 10 inch drivers in the Mini Method are the same ones that are in the Definition Pros and they are professional drivers.
I'm glad you like it, Vinnie. Between you and Zu, I've stopped looking at anybody else's amps or speakers.

Hi macrojack,

Thanks for the kind words and I am very happy to hear that you are enjoying your Red Wine / Zu combo

I didn't know that the mini-method is using the same drivers as the Definition Pros. These pro drivers are freakin' good in this little sealed-box! Any sub that can keep up with the B200s in an open-baffle is a keeper!

macrojack · « **Reply #7 on:** 25 Aug 2006, 12:07 am »

Hi Vinnie,
Imagine what the Def Pros are like with 4 of those woofers in each speaker. Fast and profound. And you can use any amp you like instead of an inboard plate amp.
As for praise -- get used to it. The way you're going it's only going to get louder.
Tom

Dmason · « **Reply #8 on:** 25 Aug 2006, 03:56 am »

It appears to be a great design; they apparently combined LOW Xmax accordian surround pro audio drivers with a sealed, or aperiodic alignment with a box tuned slightly below Fs, and it is working out well.

I like.

hayden · « **Reply #9 on:** 25 Aug 2006, 07:31 am »

Looks interesting, but I've always had a problem with the whole issue of "fast" bass. Isn't a "fast" bass driver a tweeter?

JP

macrojack · « **Reply #10 on:** 25 Aug 2006, 07:51 pm »

Hayden - When I refer to fast bass I'm speaking of acceleration and recovery times of the woofer(s) not the frequency being reproduced. Woofers have very substantial mass relative to that of tweeters. Even though the reproduced frequency is almost slow enough to count, you still need a design that can stop, start and change directions instantly. A slow moving woofer sounds sluggish, sloppy and ill-defined. We've all heard that in the car next to us at a red light.

Vinnie R. · « **Reply #11 on:** 28 Aug 2006, 07:04 pm »

Quote from: macrojack on 25 Aug 2006, 07:51 pm

A slow moving woofer sounds sluggish, sloppy and ill-defined. We've all heard that in the car next to us at a red light.

Yeah...something like this pulls up next to you with that BOOMING BASS....shaking your car so hard that you feel it and your rear-view mirror vibrates so badly that you get dizzy looking at it

Daryl · « **Reply #12 on:** 28 Aug 2006, 09:41 pm »

Hi All,

Hayden is right.

"Fast Bass" is a noexistant fairytale used by the non technically inclined and manufacturers to fool themselves and others.

For anyone interested in advancing their understanding of the technical side of audio.

Pressure from a subwoofer is proportional to the product of accelleration and surface area.

Therefore all subwoofers of the same size must have exactly the same accelleration if they are to produce the same output.

If one had higher accelleration it would be louder and you would have to reduce the volume level until it's accelleration was the same so the output level would be matched with the mains.

Subwoofers with larger cones must have less accelleration to produce the same sound as smaller subwoofers.

A 15" subwoofer that is operating at the same accelleration as an 8" subwoofer will simply be as loud as four of the 8" subwoofers operating at the same accelleration.

Once you limit the bandwidth for a subwoofer to below 100hz nothing can happen quickly it is a mathematical fact shown by Fourrier long before subwoofers existed.

Resolution in the frequency and time domains is connected the more you restrict the bandwidth in the frequency domain the less resolution can exist in the time domain.

The implications of this are that even an 18" subwoofer with a moving mass near a pound if properly designed can give flawless performance.

Quote

When I refer to fast bass I'm speaking of acceleration and recovery times of the woofer(s) not the frequency being reproduced. Woofers have very substantial mass relative to that of tweeters. Even though the reproduced frequency is almost slow enough to count, you still need a design that can stop, start and change directions instantly. A slow moving woofer sounds sluggish, sloppy and ill-defined.

As described above accelleration is just the pressure being produced by the driver.

Heavier cones are simply driven with more force to achieve the same result.

Recovery time (or settledown time) is indicated by freqeuncy/phase transfer function (which many people don't know is exactly the same thing as impulse response just another way of looking at it).

The smoother and more extended frequency/phase response is the faster a driver will settle after an impulse.

Poorly defined bass is usually indicitave of distortion.

Uneven frequency response can also cause poor bass though subwoofers with narrow peaky response curves are often described as sounding very "fast" when in fact they are the opposite.

Quote

They are light and fast paper cone drivers with a surround that is similar in appearance to the B200s ("acordian style").... as opposed to so many subs out there today with those thick rubber surrounds that need big watts to move them

Hi Vinnie,

Accordian surrounds have one application only.

They are the least resonant of all types of surrounds (and durable and cheap) which makes them suitable only for midbass/midrange drivers especially pro drivers where practicality is emphasised over quality.

Subwoofers cannot take advantage of accordian surrounds freedom from resonance because they are not used at frequencies where surrounds will resonate.

For subwoofers an accordian surround is to restrictive and their excursion capability too limited.

Foam surrounds are the best for subwoofers as far as sound quality goes due to high compliance and linearity.

rubber surrounds are tougher and better looking but suffer somewhat in terms of hysteresis and creep.

Those ZuAudio speakers look awesome and I'm glad you guy's like em but I would caution you that they are not throwing straight dice.

The response chart they are showing for their top of the line MTM is not real which means they have no idea what their speakers are really doing.

If they properly designed their speakers it would have been easy for them to include charts from their design system on the website.

The plate amps on the back of their subwoofers are the ultra cheap imports you can buy for under $100.

The prices they are charging are outragous.

Daryl

JohnR · « **Reply #13 on:** 29 Aug 2006, 01:44 pm »

"Fast" bass is a subjective description of how it sounds, for crying out loud

macrojack · « **Reply #14 on:** 29 Aug 2006, 10:16 pm »

Daryl,
Being as I'm new around here I am unaware of the credentials that qualify you to make such brash statements about the value present in Zu speakers. Are you aware of the pricing of competing products such as Wilson, Von Schweickert, Vandersteen, etc.?
The above comment from JohnR expresses what I wanted to say to you. Put your science book back in your pocket and try to comprehend that "fast" as an adjective is not meant to represent the results of years of testing but rather just a listener's attempt to characterize a sensation he wants to convey to his peers. You, sir, are a stiff-legged party pooper. Whether you know what you are talking about or not is irrelevant due to your wide misinterpretation of the meaning I wanted to convey.
Please just go back to your Mahler and Schnapps. And put your feet up.
Soon enough you can challenge somebody for claiming their tweeters sizzle.
Tom

Daryl · « **Reply #15 on:** 30 Aug 2006, 01:18 am »

"Fast Bass" being a subjective impression is a given.

Everyone is aware of it and I'm not shure why someone would think it needs to be spelled out here.

I was not commenting about anyones subjective impression but about the technical claims that were being made.

Hayden made quite an intelligent point amid a run of common audio myths being traded back and forth and was quickly and wrongly corrected.

I said for anyone interested in advancing their knowledge.

If that isn't you no harm.

Daryl

opnly bafld · « **Reply #16 on:** 30 Aug 2006, 03:34 am »

Daryl,
Maybe the technical problem comes from the fact that the "subwoofers" (woofers?) are being used at higher than normal frequencies with fullrange OB speakers.

Lin

TheSloth · « **Reply #17 on:** 2 Sep 2006, 04:46 pm »

Quote from: JohnR on 29 Aug 2006, 01:44 pm

"Fast" bass is a subjective description of how it sounds, for crying out loud

I found his post quite interesting, and don't think there's any harm in knowing the technical merits of the various design options and solutions. I'm not sure why anyone posting something technically informed tends to get flamed for invoking 'science' in the pursuit of audio reproduction. If designers stopped considering the physics of the situation, and relied purely on subjective listening tests, you'd end up with a pair of headphones that sells for $1000 and responds like this:

Oh, whoops, there already seems to be such a device...

oldtimer · « **Reply #18 on:** 2 Sep 2006, 11:36 pm »

Daryl, all drivrs sound the same then.

I think you are wrong in you assumptions. You have been hogtied by your "knowledge". The fact is that different drivers of the same size will sound different, including some sounding "fast" and other sounding "slower" It is no different to how an amp can have better pace than another amp. Not everything can be measured , but some people CANNOT hear a difference between things.

Happy listening
Nigel

opnly bafld · « **Reply #19 on:** 2 Sep 2006, 11:47 pm »

It is good to have you posting on AC Mr. Content.
Your insights are most welcome.

Lin