March Audio Sointuva Speaker

[March Audio]

I am very curious about the outcome of your project.
Do you also have a spectrogram with stepped color or the angular frequency responses of deg0-90? It is very difficult to see details.

I would have expected that the axis frequency response in the range 1.7 - 5kHz would have to be provided with a relatively wide dip to compensate for the strong widening in the horizontal radiation in this frequency range.

As I have simulations for the Bliesma tweeter already on my hard disk, it is not difficult to simulate it with the cabinet of the Sointuva, which shows the "unusual" behaviour of this tweeter.
However, the simulations are closer to the behaviour of the Bliesma-Al version than the Bliesma-Be version, because the former behaves more like an ideal 34mm tweeter.

Comparing only the simulated axis frequency response and the deg60 frequency response, the very wide horizontal directivity of the tweeter becomes obvious (low resolution, valid <10kHz):
View attachment 92389

However, the challenge lies in the crossover tuning, which has to compensate for the pronounced interaction of the baffle with the tweeter.
This is nicely shown by looking at the axis frequency responses normalized to the axis frequency response of the tweeter (low resolution, valid <10kHz):
View attachment 92390
The big challenge in my eyes is to get the range 1.5 - 5kHz under control (since the vertical directivity in this range also expands in radiation).

Or does the Bliesma-Be tweeter behave completely different in its radiation than the Al version?

Yes there have been a few challenges with the crossover, but I hope you understand I wont be going into too much detail

The sound power isnt perfect 2-6kHz, but its not leading to any significant aberration in the predicted in room response, or audible issues.

Remember these arent final measurements and have limitations, just teasers really

 

[andreasmaaan]

My bad, wrong casual terminology.

Its 250 watts long term maximum power (IEC 268-5 18.2)

-100 hour RMS – 100 hours with continous signal. o (IEC 268-5, cl 18.4 Rated noise test)
-Long Term Power Handling – 10 times alternating between signal for one minute and pause for 2 min. Total test time is 28 min. o (IEC 268-5, cl 18.2)
-Short Term Power Handling – 60 times alternating between signal for one second and pause for 1 min. Total test time one hour. o (IEC 268-5, cl 18.1)

The test signal is a weighted (IEC 268-1) pink noise signal with a crest factor of two.

I have no doubt the signal is filtered, but not sure of precise range.

What needs to be borne is the nature of music and its actual RMS (heating value) is very low compared to the peak. Typically 1/5th.

FYI, IEC 268-5 specifies a pink noise test signal with a crest factor of 6dB that is highpass-filtered 12dB/octave at 40Hz and lowpass-filtered 12dB/octave at 5kHz.

 

[March Audio]

Predicted in room response (1dB/octave slope)

 

[andreasmaaan]

Predicted in room response (1dB/octave slope)

View attachment 92396

Is this valid for the bass region?

 

[ironhorse128]

It seems that @March Audio was trying to create a cost-almost-no-object great speaker. It seems that a lot of effort and cost was going into the ability of the speaker to go low (hit 40hz). I personally use subs that XO at 80hz to 100 hz.

@March Audio : How would the a cost-almost-no-object great speaker design change if hitting 40hz would not be necessary. E.g. are the passive radiators useless? Is the purify woofer overkill?

 

[March Audio]

It seems that @March Audio was trying to create a cost-almost-no-object great speaker. It seems that a lot of effort and cost was going into the ability of the speaker to go low (hit 40hz). I personally use subs that XO at 80hz to 100 hz.

@March Audio : How would the a cost-almost-no-object great speaker design change if hitting 40hz would not be necessary. E.g. are the passive radiators useless? Is the purify woofer overkill?

That wasn't the intention, if it were cost no object it would be quite different and certainly not passive .

The purifi woofer is fantastically low distortion which is subjectively quite noticeable and beneficial. It goes low in relatively small box. However its properties means you need a long port or PRs. It's really not just about trying to get to 40Hz, but that extra depth is definitely subjectively beneficial.

Subs of course are an option but they aren't always easy to integrate well. You really need bass management, something most non AV systems don't have. Also not always domestically acceptable, so its not an option for everyone.

 

[McFly]

The first prototype speakers I whipped up with my purifi 6.5 woofers I was hitting 30hz easy in my room, with authority. The lack of distortion makes you play them way too loud. The woofers bottom out before they distort. And from a 15L ported box. It was jaw dropping and not much does that after so many years in the hobby. The woofers are so clear when listened to you actually have to recalibrate with everything you listen to through them, they are that good. If March Audio gets the crossover and DI right, these will be endgame “ear-opening” speakers for most.
State of the art 2-way with probably the best “SINAD” of any small bookshelf to date. The clarity is spooky at first.
I wish you all the best with sales, would demo myself if I didn’t already own my own version.

 

[restorer-john]

@March Audio Do you have a ballpark AUD figure for these puppies?

 

[March Audio]

@March Audio Do you have a ballpark AUD figure for these puppies?

Can't say quite yet, but soon

 

[jonm42]

@March Audio any chance of a rough timeline for ordering?

 

[March Audio]

@March Audio any chance of a rough timeline for ordering?

Aiming for beginning of December.

 

[jonm42]

I think a pair of these driven by a P452 would make me a lovely present for myself ...

 

[Ilkless]

Predicted in room response (1dB/octave slope)

Keeping the dispersion matched at crossover to +/- 0.5dB with a direct radiating 2-way that size is one hell of an achievement.

 

[March Audio]

Keeping the dispersion matched at crossover to +/- 0.5dB with a direct radiating 2-way that size is one hell of an achievement.

There has been a certain degree of blood sweat and tears thats for sure

 

[jonm42]

@March Audio Purifi bundle with Sointuva and a pair of P451s or a P452? All Purifi, all the time!

 

[HooStat]

Are you sending a pair to @amirm ?

 

[Mnyb]

It seems that @March Audio was trying to create a cost-almost-no-object great speaker. It seems that a lot of effort and cost was going into the ability of the speaker to go low (hit 40hz). I personally use subs that XO at 80hz to 100 hz.

@March Audio : How would the a cost-almost-no-object great speaker design change if hitting 40hz would not be necessary. E.g. are the passive radiators useless? Is the purify woofer overkill?

I would also XO to a sub at 80Hz but an argument can be that to make a proper xo both the sub and speakers needs to extend an octave beyond the intended xo point ? so 40Hz for an 80Hz xo seems about right , note it does not have to do this at high levels its just has to be linear in the passband. and likewise the sub needs to reach 160hz. It makes for more predictable xo slopes .
Sure we can DSP it to be right but the actual acoustic slopes depends on booth the speaker and the sub.

In fact this mini monitor , goes on my shortlist for future uppgrade , I usually prefer to use sub with small floor standers for the reasons outlined above and the midbass capacity . But this could be the base for an actually working small speaker + sub setup ? nicely done

Good effort seems like a very good speaker.

Does it come in any wood grain(pics please) . my current speaker's are piano black and iv'e come to appreciate wood finishes more .
the age gracefully, clear lacquer does not. Especially not white its just get scratchy.
Even spotty and scratchy wood has acceptable patina as they age , just imho.

More questions .

The round over at the edges ? could it be even bigger to help more with diffraction afaik they need to be substantial to help. They are esthetically horrible anyway , so better optimize for function in this case is it not ?

Baffle proportions how is this chosen ?

 

[jonm42]

Does it come in any wood grain(pics please)

A rough list, perchance? Understand if not yet possible.

 

[March Audio]

I would also XO to a sub at 80Hz but an argument can be that to make a proper xo both the sub and speakers needs to extend an octave beyond the intended xo point ? so 40Hz for an 80Hz xo seems about right , note it does not have to do this at high levels its just has to be linear in the passband. and likewise the sub needs to reach 160hz. It makes for more predictable xo slopes .
Sure we can DSP it to be right but the actual acoustic slopes depends on booth the speaker and the sub.

In fact this mini monitor , goes on my shortlist for future uppgrade , I usually prefer to use sub with small floor standers for the reasons outlined above and the midbass capacity . But this could be the base for an actually working small speaker + sub setup ? nicely done

Good effort seems like a very good speaker.

Does it come in any wood grain(pics please) . my current speaker's are piano black and iv'e come to appreciate wood finishes more .
the age gracefully, clear lacquer does not. Especially not white its just get scratchy.
Even spotty and scratchy wood has acceptable patina as they age , just imho.

More questions .

The round over at the edges ? could it be even bigger to help more with diffraction afaik they need to be substantial to help. They are esthetically horrible anyway , so better optimize for function in this case is it not ?

Baffle proportions how is this chosen ?

These will be manufactured to order so can be supplied in any colour you like or have wood finishes.

 

[jonm42]

I'm thinking Bubinga, Cocobolo, Cherry, Mesquite, ...