HF10AK + 12P80ND + custom WG

[limacon]

Hi!

I've fallen down a rabbit hole of making a new speaker with the following drivers.

HF10AK
12P80NDv2

I have designed a constant directivity wave guide using ATH4 for the HF10AK. The simulated response is flat to +/- 0.5 dB between 1k and 10k out to 45deg off axis with a drop of 2.5dB by 15k. Plots are based on 100 points, 4mm mesh resolution.

I spotted a few posts from LineSource regarding "clever" enclosures so I will try that too - it looks like the Beyma can be forced to an f3 of about 85Hz.

The Beyma is mounted such that the acoustic center is similar to the Faital and held in place from the rear with a mouting ring of alumnium.

More to follow. Thanks for looking.

 

[skogs]

This looks like a great project, and looking forward to seeing measurements. Will you be using passive or active crossovers?

 

[puppet]

Likewise, looking good.

 

[limacon]

This looks like a great project, and looking forward to seeing measurements. Will you be using passive or active crossovers?

At the moment I use an EV DC-one dsp with an MC2 T4 250 amplifer


The EV DC One has the following components

ADCs
CS5381 with MC33078 opamps
-110 THD / 120 DR

DACs
CS4398 with MC33078 and NE5532 opamps
-107 THD / 120 DR

AES DIGITAL IN
DA101C transformer into a CS8416

DSP
ADSP-21369

 

[limacon]

Likewise, looking good.

Thanks! A quick lick of paint and drivers mounted for the prototype test!

 

[limacon]

A very quick and dirty 800Hz BW3 at 15 (blue), and roughly 30(green) and 45(brown) off axis. 1/12th smoothing, no EQ. The 2k dip is found in the Faital res curve. I'll be a little more scientific over the weekend.

 

[skogs]

Looks very good so far! Could you do me a huge favour, and post a spectrogram with the wavelet-setting?

similar to this:
https://www.diyaudio.com/forums/attachments/multi-way/879688d1601374768-reading-wavelet-spectrogram-0-5msinverted-png

 

[chris661]

Are you sure that's an 800Hz highpass?

Looks like the acoustic -3dB point is 500Hz.

Chris

 

[limacon]

400 to 16k simulation chart attached. 100 points, 4mm mesh resolution.

 

[limacon]

Are you sure that's an 800Hz highpass?

Looks like the acoustic -3dB point is 500Hz.

Chris

DC-One is actually set to 800 24dB BW.

 

[limacon]

Looks very good so far! Could you do me a huge favour, and post a spectrogram with the wavelet-setting?

similar to this:
https://www.diyaudio.com/forums/att...reading-wavelet-spectrogram-0-5msinverted-png

I'm not that familar with REW just yet. Is there a guide to set / run this ?

 

[puppet]

The EV may have issues controlling the driver. I don't think that's uncommon. Final filters will require conformation/adjustment.

 

[chris661]

DC-One is actually set to 800 24dB BW.

Are you sure?

If so, that would suggest that the raw driver response actually rises steeply below 800Hz, in order to make the resulting response (which you've measured) approximately flat to 500Hz.

Chris

 

[Ro808]

The EV may have issues controlling the driver. I don't think that's uncommon. Final filters will require conformation/adjustment.

You mean 'correcting the output to the driver'? .

 

[puppet]

Thanks for the translation Rob ... but who can say which.

 

[limacon]

High pass disabled at approx 1m at 0, 15, 30 and 45 in a not so amazing room with notch and 3.5k 5db highshelf only. 1/12th smoothing.

 

[limacon]

Learning REW. Hope to create new charts soon.

 

[kipman725]

great looking speaker Limacon, reminds me of my QSC clone waveguides. If your around the north west? I have a battery powered amp, measurement mic etc. happy to help out

 

[limacon]

Hey kipman725, thanks! It is work in progress. I'm down in Nottingham. I might end up with a wood cabinet with a machined anodized aluminium wg and woofer ring.

 

[limacon]

Speaker building montage backing track

Zombie Hyperdrive - Imperium FULL ALBUM (2020) - YouTube