INVOLVE - Y4 surround sound system reviews

[chucky3042]

Well surroundies

Its about time that I do a review of the Bass performance on the standard bookshelf Y4 electrostatic surround sound system.

In my opinion our bass sounds thin and sterile!

Our dual woofers cut in at around 200 Hz give or take and it is produced by 2 separate woofer consisting of 2 x 5 inch drivers in a really weird arsed balanced sorta ported sorta not configuration designed by a Yugoslavian madman (Zel). One of our issues is we 3 audio guru's Dave the *****, Wayne and my humble self have all been fed a diet of electrostatic speakers for many years and hardly ever go back to conventional cones. I prefer full range electrostatics and that is why I am currently building my monster super speaker,

It took us forever to make a woofer sound as clinical as the electrostatics and most of our comparisons sounded like muffled mud until the crazy Zel did his thing. This is all confused these days with the dominance of "home theater" where the expectation is to turn the bass up by around +10 dB to match the thump in cinemas. Indeed at home I use my Y4 exclusively for home cinema and I am probably guilty of turning the bass up a bit also, silly me.

In recent weeks I have been doing some fine tuning of the Y4 compensation stuff and I have finally settled on an improved arrangement. We needed a litmus test as a comparison and Wayne had a spare "Paradigm Reference studio 20 v5" that had a 7 inch bass driver.and it had a frequency response that looked like this (cannot figure how to rotate it:
View attachment 110934View attachment 110935

As you can see it falls off at around 110 Hz.

In comparison below is the measured bottom end frequency response of our Y4 system:
View attachment 110938

ALL PLOTS WERE DONE IN A REAL ROOM WITH PINK NOISE AT AROUND 3 METERS

As you can see we extend to around 50 Hz and quite flat.

So the question is which system sounds more "bassy" the Y4 or the Paradigm?

ANSWER....The Paradigm - by a country mile! By initial comparison we sound thin and very sterile yet we measure flat as a tack with bugger all distortion components. After much soul searching and more investigation that I can show you guys if asked the huge difference is in the impulse decay response of conventional cones that bong for 2 -10 ms after an impulse adding a world of "color" to the sound that we have all grown to expect and actually like. In the case of the electrostatic this bong is actually gone after 0.1 ms and this means there is an absence of sound and we interpret this as sounding thin or sterile.

Once you have spent some time listening to electrostatics you discover that you get headaches listening to conventional cone speakers as the brain has to work a bit harder sorting out what is represented by the sound. Getting the cone dual 5 inch bass drivers to have this sterile electrostatic sound took ages. I still want my full range monster.

Well surroundies

Its about time that I do a review of the Bass performance on the standard bookshelf Y4 electrostatic surround sound system.

In my opinion our bass sounds thin and sterile!

Our dual woofers cut in at around 200 Hz give or take and it is produced by 2 separate woofer consisting of 2 x 5 inch drivers in a really weird arsed balanced sorta ported sorta not configuration designed by a Yugoslavian madman (Zel). One of our issues is we 3 audio guru's Dave the *****, Wayne and my humble self have all been fed a diet of electrostatic speakers for many years and hardly ever go back to conventional cones. I prefer full range electrostatics and that is why I am currently building my monster super speaker,

It took us forever to make a woofer sound as clinical as the electrostatics and most of our comparisons sounded like muffled mud until the crazy Zel did his thing. This is all confused these days with the dominance of "home theater" where the expectation is to turn the bass up by around +10 dB to match the thump in cinemas. Indeed at home I use my Y4 exclusively for home cinema and I am probably guilty of turning the bass up a bit also, silly me.

In recent weeks I have been doing some fine tuning of the Y4 compensation stuff and I have finally settled on an improved arrangement. We needed a litmus test as a comparison and Wayne had a spare "Paradigm Reference studio 20 v5" that had a 7 inch bass driver.and it had a frequency response that looked like this (cannot figure how to rotate it:
View attachment 110934View attachment 110935

As you can see it falls off at around 110 Hz.

In comparison below is the measured bottom end frequency response of our Y4 system:
View attachment 110938

ALL PLOTS WERE DONE IN A REAL ROOM WITH PINK NOISE AT AROUND 3 METERS

As you can see we extend to around 50 Hz and quite flat.

So the question is which system sounds more "bassy" the Y4 or the Paradigm?

ANSWER....The Paradigm - by a country mile! By initial comparison we sound thin and very sterile yet we measure flat as a tack with bugger all distortion components. After much soul searching and more investigation that I can show you guys if asked the huge difference is in the impulse decay response of conventional cones that bong for 2 -10 ms after an impulse adding a world of "color" to the sound that we have all grown to expect and actually like. In the case of the electrostatic this bong is actually gone after 0.1 ms and this means there is an absence of sound and we interpret this as sounding thin or sterile.

Once you have spent some time listening to electrostatics you discover that you get headaches listening to conventional cone speakers as the brain has to work a bit harder sorting out what is represented by the sound. Getting the cone dual 5 inch bass drivers to have this sterile electrostatic sound took ages. I still want my full range monster.

Just to show more about my point on the "bong" after an impulse and the "coloration" of all objects (including electrostatics), below are a few Impulse decay responses or CSD plots we did a while ago:

Here is a plot of the panel we use in the bookshelf Y system (electrostatic + our dual 5 inch balanced woofers)

As you can see most of the bongs are gone after 100 microseconds (0.1 ms) and are more than 20 dB down, and given my 12 dB rule you will tend not to hear them.



Below is the plot for a Martin Logan Summit hybrid electrostatic speaker .....its around $20 K but the woofer always sounded like mud to me, also the curved array causes all sorts of issues. Perhaps this is why!

As you can see there are all sorts of additional resonant sound well after 1 ms.




And below is a very well designed speaker with amazing crossover componentry the Whise 113. It was a 2 cone unit

All sorts of stuff happening. In all other parameters the Whise tested great but frankly sounded crap to my ears.

So my overall point is that frequency response is important but there is way more to the story than it shows. A good speaker can be an absence of sound . Not just harmonic distortion but also the resonant bonging. Much of what we perceive as bass is often this additional resonant "warmth"

 

[kfbkfb]

Pre-distortion?

Since the "fidelity error" in the cone speakers has been quantified, maybe a (digital) pre-distortion scheme - add a calculated resonant sound to the input signal (opposite phase) so that it (mostly) cancels out the cone speaker resonant sound.


Kirk Bayne

 

[barfle]

Hmmm. Of course, I have no insight into the designs, but the complaint about “bong” and “impulse” makes me wonder about damping factor at the driver. What sort of impedance does the crossover show the driver?

With just enough knowledge to be dangerous, I realize I’m barking up a tree that might not have a squirrel in it.

 

[chucky3042]

Thanks Barfle and Kfbkfb

You are both correct but doing the pre distortion thing is challenging and would be a job for a PhD candidate me thinks! My own gut feeling is to get it right mechanically and reduce the bongs to as close to zero as possible. We achieved it in our dual 5 inch subs but its a hard road. One reason I am pursuing my monster super electrostatic is that electrostatics naturally are extremely low in the bongs. The mylar diaphragm material we use is only 3.5 uM thick - the same weight as 6 mm of air (quarter of an inch)! This is then naturally damped by the air on either side and in most instances in the speaker cloth covering the panels (they look more sexy without the cloth but bong slightly more).

Yes in conventional cones its all about stiffening the box , damping internally - although this does reduce available energy. Also there is a trade off with ports- they measure more bass but some of that is bong.

This morning we compared two more speakers, one was the Whise113 and the other was a bookshelf 2 way Whatmough (very good local brand)

In terms of frequency response they were very similar, see below:

Whise 113
Yes get over it, Dave does paint his nails....a nice beetle color

And the Whatmough

So the question is - given that both these speakers have a similar bottom end frequency - which one sounded Bassyer?

The answer is that the Whatmough sounded way cleaner but it was considerably down in bass compared to the Whise that sounded much fuller. I would chose the Whatmough every day.

In short, the Whatmough would have less bonging and probably less THD

So Chuckies rule is that if you are selecting a speaker against another with a similar frequency responce- PICK THE ONE THAT SOUNDS LESS BASSY! It will be cleaner.

 

[kfbkfb]

Any music suggestions for evaluating speaker bass accuracy?


Kirk Bayne

 

[barfle]

There seems to be a bit of witchcraft in the science of acoustics. I'm interpretating the term "bong" to be a ringing of the diaphragm sort of like a bell continues to vibrate after it receives the impulse. Of course the bell is meant to continue its sound after being struck, and we want our paper (or even metal) cones to only do what we tell it to do when we tell it. Cabinet bracing, port tuning, crossover efficiency, lots of factors in play with resonance.

Glad it's your problem and not mine.

PS, Dave's fingernails are lovely. And probably can be used to loosen screws.

 

[chucky3042]

Any music suggestions for evaluating speaker bass accuracy?


Kirk Bayne

For this evaluation we used:

Robbie Williams-beyond the sea (I hate Robbie but its a nice track with lots of big band energy and balance)

Jazz at the pawn shop - really good to see if its just a one note bass

Brian Setzer - Town without pity (we call it the track without pity) Again full spectrum big band energy and it quite literally has blown amplifiers and speakers up. We use it also to check the tonal balance.

 

[chucky3042]

There seems to be a bit of witchcraft in the science of acoustics. I'm interpretating the term "bong" to be a ringing of the diaphragm sort of like a bell continues to vibrate after it receives the impulse. Of course the bell is meant to continue its sound after being struck, and we want our paper (or even metal) cones to only do what we tell it to do when we tell it. Cabinet bracing, port tuning, crossover efficiency, lots of factors in play with resonance.

Glad it's your problem and not mine.

PS, Dave's fingernails are lovely. And probably can be used to loosen screws.

Yes spot on, everything in your room is a bell - desk, plate, window, wall, cup. Just try tapping everything around you with a drumstick and you will find everything has its own and different characteristic sound. The challenge is to make it as dead as possible but yet fast in response.