March Audio Sointuva Speaker

[March Audio]

@AudioJester

A quick and dirty ground plane measurement indicated below seems to confirm this (within reason).

Of course most us listen in rooms where boundary reinforcement is inevitable (along with the corresponding cancellations)

0.5m from a boundary which puts F3 below 40Hz!

My experience is that with these speakers you do start to "feel" the lowest frequencies almost sub like.

 

[Ilkless]

Lovely, especially for sub-5k. The cabinet reminds me of what Mike Lenehan did in the Gold Coast with the gloss paint and roundovers. That said, what I don't like about the Purifi is that its unique properties make passive radiators almost a necessity, raising the cost of admission substantially (especially if using Purifi's own PR). So from a single driver that was undercutting the Scan Revelator/Illuminator/Ellipticor and SEAS Excel (which all work okay with ported boxes) for superior performance, it becomes a much more expensive system with its supporting components. If size wasn't a constraint, one would be hard-pressed to decide against adding more drivers, either for 2.5-way or even 3-way. That's why my initial enthusiasm for Purifi has dulled somewhat.

 

[March Audio]

@AudioJester

Sointuva compared to a similar sized Usher BE718 in the same position

 

[fredoamigo]

superb realization ! ... even if it is still a prototype is it possible to see a picture of the crossover ?

 

[March Audio]

superb realization ! ... even if it is still a prototype is it possible to see a picture of the crossover ?

Thank you for the kind words but hell no its a mess PCBs are being manufactured. We havent done anything with fancy caps BTW, just good polys. What we have done is had a custom inductor wound for the woofer XO to minimise loss and maximise sensitivity (which is about 85.5dB). It weighs 1.6kg and the big challenge is making sure it stays put during shipping

 

[March Audio]

Impedance plot. Just nudges 4 ohms minimum. Phase angle shouldnt cause problems for any decent amps.

 

[Juhazi]

shouldn't ?

 

[March Audio]

shouldn't ?

Corrected

 

[restorer-john]

I really like the look of the speaker and I'd like to hear a pair. How does it go at high levels of LF content with twin passive radiators?

I suggest putting a captive nut in the base for secure stand-mounting if you haven't done so already.

I know it's just a prototype, but the March~audio logo fonts on the metal badge are all different to your normal logo.

 

[March Audio]

I really like the look of the speaker and I'd like to hear a pair. How does it go at high levels of LF content with twin passive radiators?

I suggest putting a captive nut in the base for secure stand-mounting if you haven't done so already.

I know it's just a prototype, but the March~audio logo fonts on the metal badge are all different to your normal logo.

Hi John

Already addressed the font I should swap the plates over.

I like the idea of the captive nut but it would mean people have to use specific stands. Maybe our own stands


How do the PRs cope with high level LF? Spectacularly well . The distortion of the woofer/PR is very low, will post some measurements at some point but it is really clean. Just for fun a video of some bass heavy tracks. Its at close quarters but the SPL meter was overload on peaks with its range set to 110dB.

 

[CtheArgie]

Hi John

Already addressed the font I should swap the plates over.



I like the idea of the captive nut but it would mean people have to use specific stands. Maybe our own stands


How do the PRs cope with high level LF? Spectacularly well . The distortion of the woofer/PR is very low, will post some measurements at some point but it is really clean. Just for fun a video of some bass heavy tracks. Its at close quarters but the SPL meter was overload on peaks with its range set to 110dB.

Allan,
the speakers I built, designed by others who know, have the crossovers outside of the speaker box, in their own box. I wouldn’t mind the same in yours...
Would that be easier to build?

 

[March Audio]

Allan,
the speakers I built, designed by others who know, have the crossovers outside of the speaker box, in their own box. I wouldn’t mind the same in yours...
Would that be easier to build?

Not really easier to build, we would have to make another box for them.

Whilst it is true that components can suffer microphonic effects from vibration you need to put it into context. The signal levels that you might create are infinitesimal compared to those going to the drivers. Its a non issue.

Now external DSP XO with amplification, now thats a whole different matter

 

[restorer-john]

Maybe our own stands

That's what I was thinking. The threaded hole is already there, The stands come with the right bolt, pads, spikes/cups and can be fillable with leadshot/sand and are tuned for the correct height. Look at some of Jamo's Danish designs from the past for inspiration- they made some really attractive stands for their speakers.

Good money in stands for both you and possible resellers as they are flatpacked and compact. Transport damage is virtually impossible if sensibly packed. Most quality matching powerdercoated stands seem to hover around $600-900, so there's a lot of fat to play with. With ~$5K speakers sitting ~2 feet off the ground, it makes sense to have a secure footing. Use Australian steel and have them locally fabricated and finished.

You can also do promos at times where you can bundle the speakers and get the stands at xx% off via redemption or something like that.

 

[dougi]

Not really easier to build, we would have to make another box for them.

Whilst it is true that components can suffer microphonic effects from vibration you need to put it into context. The signal levels that you might create are infinitesimal compared to those going to the drivers. Its a non issue.

Now external DSP XO with amplification, now thats a whole different matter

I assume there is too much risk in allowing a custom order for dual binding posts and no xover to allow the latter? ie risk a customer could destroy drivers under a warranty.

 

[MZKM]

shouldnt cause problems for any amps.

-45° & 5ohm @100Hz, that seems challenging to me, especially as sensitivity is going to be a bit lower than average. So, if you have high powered Class-D amp (hmm, wonder who I’d buy one of those from ) then yeah no problem, but I’d be hesitant if using a <$1000 AVR.

 

[March Audio]

I assume there is too much risk in allowing a custom order for dual binding posts and no xover to allow the latter? ie risk a customer could destroy drivers under a warranty.

Yes I think so, although people manage to destroy tweeters with crossovers (I have done it myself), plus Im afraid we cant cater for every customer requirement. It does eat up time and resource.

 

[AudioJester]

Thats impressive bass and driver movement!

So does the rear passive radiators create a cardioid bass response? I am assuming the radiators dont go up to the 1.5kHz crossover point.
Trying to understand how it works. Apologies for my ignorance.
What happens if you put active drivers in the back?? Kaboom??

 

[Chromatischism]

Very nice. I have the "budget" versions of these from SB Acoustics. What they've done at Purifi is very interesting.

I find the first half of this track to be a good bass/excursion test:

Starset - A Brief History Of The Future

 

[Chromatischism]

Thats impressive bass and driver movement!

So does the rear passive radiators create a cardioid bass response? I am assuming the radiators dont go up to the 1.5kHz crossover point.
Trying to understand how it works. Apologies for my ignorance.
What happens if you put active drivers in the back?? Kaboom??

They are tuned similarly to how a port would be tuned, so they don't go that high.

 

[March Audio]

-45° & 5ohm @100Hz, that seems challenging to me, especially as sensitivity is going to be a bit lower than average. So, if you have high powered Class-D amp (hmm, wonder who I’d buy one of those from ) then yeah no problem, but I’d be hesitant if using a <$1000 AVR.

Of course only our amps should be used. Its the only way to guarantee maximum performance and pleasure

Seriously though, I dont think its that bad and should be happily in the capabilities of any decent amp. I suppose its a bit of a subjective area as what is defined as a decent amp. Clearly a multichannel AVR is the worst case for potential power dissipation issues, but it is a peak dissipation. Not sure if its a combination you would expect to see that often though, cheap AVR and "expensive" speaker

Actual values are:

F______________Z____________P
98.7________5.308_________-42.552
101.5_______5.154_________-40.541

Sensitivity is over 85dB BTW so managed to get it to "average levels"

Looking through Amirs speaker tests there are many that have areas where the phase angle creates "equivalent" impedances around 3 ohms.