Than we (and the "dictionary") have a VERY different idea of listening fatigue, lol
Welcome miscommunication
Hey jim, was not directed at you personally, I just had the impression that the following sentence ...
... was mystifying rather then disclosing, re system sound properties. The Purifi tweeter looks hot, no doubt (do not all of their products?), yet the question of DI tendency revolves around dispersion, which can be managed for many tweeters that are around already. And it is indeed a very central question since the renaissance of the spinorama metric, and the by now kind of generalized verdict from the famous M2 vs Salon2 thread: Gradually rising DI > flat.
... was mystifying rather then disclosing, re system sound properties. The Purifi tweeter looks hot, no doubt (do not all of their products?), yet the question of DI tendency revolves around dispersion, which can be managed for many tweeters that are around already. And it is indeed a very central question since the renaissance of the spinorama metric, and the by now kind of generalized verdict from the famous M2 vs Salon2 thread: Gradually rising DI > flat.
Hello All,
I do not have a SPK16 tweeter to play with.
I do have a couple of 8" Purifi aluminum woofers to test drive with and without Passive Radiators. The GRAS 46BF-1 is the inside the box microphone. A ring of keys resting on the enclosure along with a Rub and Buzz test sweep shows up enclosure panel resonance. The keys dance and make noise for the test microphone.
I will try my hand at tuning the Woofer/Enclosure with the impedance curve, Theile Small type Parameters and microphones inside and outside the box measurements.
Thanks DT
I do not have a SPK16 tweeter to play with.
I do have a couple of 8" Purifi aluminum woofers to test drive with and without Passive Radiators. The GRAS 46BF-1 is the inside the box microphone. A ring of keys resting on the enclosure along with a Rub and Buzz test sweep shows up enclosure panel resonance. The keys dance and make noise for the test microphone.
I will try my hand at tuning the Woofer/Enclosure with the impedance curve, Theile Small type Parameters and microphones inside and outside the box measurements.
Thanks DT
Interesting, as i expect to receive my 8" purifi's shortly. Question: does it matter how the mic in box is mounted? I see @HiFiCompass sticking it in, other put entire mic in the enclosure, or mount a tweeter in one of the panels
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Thanks for letting me know about this...I am checking to see if my flavor of FA253 is compatible.
Interesting, as i expect to receive my 8" purifi's shortly. Question: does it matter how the mic in box is mounted? I see @HiFiCompass sticking it in, other put entire mic in the enclosure, or mount a tweeter in one of the panels
Hello All,
At this point I have not done a microphone in a box before. I do have a couple of different 1/4inch GRAS microphones to try out. The plan is to drill a 5/16 inch hole into the back of the test enclosure then insert the test microphone through the wall of the enclosure. The next move is to seal the microphone in place with some blue tack stuff.
I have the 8 inch 8R Purifi drivers in hand the Passive Radiator's are a few weeks out. I am thinking of two Passive Radiators per enclosure and measuring the output of the speaker with different weights on each of the two PR's.
If you think about it, the microphones are pressure sensors, they are calibrated in SPL or mv per Pascal. I do like the idea that a reflex port, PR or a aperiodic restive vent will lower the peak pressure inside the enclosure. The enclosure wall will have much lower peak force pushing on each wall. the enclosure wall flex much less. Too Much Fun.
Thanks DT
If you're going for that many more PR's you might as well get another woofer for the same price?
I personally only use PR's when there are no other solutions anymore, because the price/performance ratio of most PR's is pretty poor.
With an extra woofer you already win 6dB overal, which is very substantial.
Closed boxes are much easier to make and position + you could go for a impuls corrected solution and all kinds of other fancy solutions.
ESPECIALLY with a DSP.
I find it kinda bizarre news, why on earth it took SO long?
Their SigmaDSP IC's support this out of the box.
That is an interesting observation, Juhazi - I have also found that differerent speakers will sound nearly the same if they are eq'd to have the same on-axis response (at least when listening on-axis)... but all of my experiments have been with speakers that have very similar radiation patterns. In your experiment, the AINO and coax have very different patterns...
I assume a mixture between pandemic parts shortages, price increases and investment models. There was a short discussion at ASR but I do not remember if their staff making this statement.
@sheeple
All those things don't have anything to do with a simple software implementation?
They still use the same ADAU145x chip, even with their older ADAU170x system this could be done (just extremely limited, but doable)
But yes, those IC's were a totale pain and impossible to get for a while (I had to cancel quite A LOT of projects for that same reason)
All those things don't have anything to do with a simple software implementation?
They still use the same ADAU145x chip, even with their older ADAU170x system this could be done (just extremely limited, but doable)
But yes, those IC's were a totale pain and impossible to get for a while (I had to cancel quite A LOT of projects for that same reason)
My limited understanding of the capabilities of the chip made me believe in a statement of another user in the Hypex-thread, that FIR was introduced with the ADAU1452. And previous discussion revolved around the calculation power to provide enough taps. All of which I do not understand much about ...
Anyway, I wont pay another 900 EUR only to acquire FIR capabilities, to buy again a product that I already own. That's just a tad too steep.
Anyway, I wont pay another 900 EUR only to acquire FIR capabilities, to buy again a product that I already own. That's just a tad too steep.
Hello,
This is not the endgame. This is primarily for the fun of doing and learning. Plus playing with the new Microphone In the Box tool. We will see how that works out.
I like the measurements and sorting the data.
I like sorting out puzzles.
I like what the SPK16 with the 6 1/2 inch Purifi did for extending the Bass Frequencies
If I do find something that I like, I will use it for awhile in the listening room until the next one is more interesting.
Thanks DT
Hello All,
Today I have been playing with a ScanSPEAK PL17WJ-00-08 Mid-Bass driver in a sealed Denovo 0.55 cubic foot enclosure.
I drilled a 5/16 inch hole in the front Baffle where a tweeter will be installed, if there will ever be one. I ran the APx500 Acoustic software add on, including impulse, both with the GRAS pressure microphone inside the box and outside the box about 10 inches away from the center of the driver.
It is interesting to see the dB SPL measurements inside and outside. At 2.83V input the dB SPL inside inside the box was up at 135dB ish. This would overload many microphones. The impulse bounced around inside the box for 7 times longer than in the room with the microphone outside the box. The ringing inside the box may may have affected the speaker response in the room. That is for future consideration. There are more impressions and observations yet to be considered.
The dB SPL measured outside the box was much flatter than inside. The pressure inside the box drops of quickly with increasing frequency. First impression is that the measured in the box pressure modulates with the ripples in the impulse response.
Next time we will see what happens to the impulse inside the box with some sort of vent in the box.
I used this new old stock off the shelf driver to avoid upsetting someone about their current favorite driver.
Thanks DT
Edit: Oops mistake labeled the impulse plots backwards.
The top trace is measured out of the box.
The bottom trace is measured in the box.
Today I have been playing with a ScanSPEAK PL17WJ-00-08 Mid-Bass driver in a sealed Denovo 0.55 cubic foot enclosure.
I drilled a 5/16 inch hole in the front Baffle where a tweeter will be installed, if there will ever be one. I ran the APx500 Acoustic software add on, including impulse, both with the GRAS pressure microphone inside the box and outside the box about 10 inches away from the center of the driver.
It is interesting to see the dB SPL measurements inside and outside. At 2.83V input the dB SPL inside inside the box was up at 135dB ish. This would overload many microphones. The impulse bounced around inside the box for 7 times longer than in the room with the microphone outside the box. The ringing inside the box may may have affected the speaker response in the room. That is for future consideration. There are more impressions and observations yet to be considered.
The dB SPL measured outside the box was much flatter than inside. The pressure inside the box drops of quickly with increasing frequency. First impression is that the measured in the box pressure modulates with the ripples in the impulse response.
Next time we will see what happens to the impulse inside the box with some sort of vent in the box.
I used this new old stock off the shelf driver to avoid upsetting someone about their current favorite driver.
Thanks DT
Edit: Oops mistake labeled the impulse plots backwards.
The top trace is measured out of the box.
The bottom trace is measured in the box.
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Encouraging such experiments, I wonder what your objective is here. Wall resonances occur typically around or above 400Hz. There is hardly anything like a balloon effect at low frequencies. If you’re interested in measuring standing waves inside the enclosure, best place the microphone in a corner.