I can't read Polish, but this dip around 300Hz happens in all their measurements.
Obviously upper range is gated rather short, causing dip below 400Hz. Bass is some kind of nearfield, without baffle step correction and perhaps spl compensation isn't spot on.
This difficulty can be seen with Stereophile etc, merged meaasurements as well. Room response should be very good!
Obviously upper range is gated rather short, causing dip below 400Hz. Bass is some kind of nearfield, without baffle step correction and perhaps spl compensation isn't spot on.
This difficulty can be seen with Stereophile etc, merged meaasurements as well. Room response should be very good!
Marcel,
Your FLANGE-57-76 for bolts at 3x57 and 4x76 mm pitch
and the FLANGE-57-76-102 also for the pitch 4x102 mm
_______________________________________________
Looks like you may still need more holes for the new B&C "HLX" helical throat drivers:
B&C DH350, Two M5 holes 180° on 53 mm (2.09 in) diameter.
B&C DH450, Two M5 holes 180° on 57 mm (2.24 in) diameter.
The smaller one is due for release around June of 2024, the larger more like October.
There may be some samples available in advance of the release...
Art
The flange shown above is already the one for the DH drivers (2x53 + 2x57).
- I'm really curious how they managed to create the advertised flat wavefront at the exit. I'm a bit sceptical but let's wait and see (there also seems to be quite a sharp change in cross-section area right at the exit, surprisingly). Definitely, the zero exit angle should be a good match to my new waveguides, as I started to use a straight tube at the entrance.
- I'm really curious how they managed to create the advertised flat wavefront at the exit. I'm a bit sceptical but let's wait and see (there also seems to be quite a sharp change in cross-section area right at the exit, surprisingly). Definitely, the zero exit angle should be a good match to my new waveguides, as I started to use a straight tube at the entrance.
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It looks like the first priority was to make it look like an alien spaceship. The functionality aspect as a speaker probably only came next 😀 😀
Waiter, I’ll take a pair of those, and a pair of these, to go, please.
First measurements with the new B&C 1-inch compression driver
https://josephcrowe.com/blogs/news/b-c-dh350-1-compression-driver
Now I don't know if I should be as excited about this driver as before.. 🙂
https://josephcrowe.com/blogs/news/b-c-dh350-1-compression-driver
Now I don't know if I should be as excited about this driver as before.. 🙂
It looks correctable, though. DI is nice, distortion is relatively low.
Because of some other work pressure, I am not able to do much audio-related stuff of late.. 🙂
However, some slow work is in progress (by my friend) for finishing the EXAR 400 waveguides I had printed last year.. 🙂
1. Petals (printed in ABS) glued and lightly sanded
2. Primer coating
3. Puttied
4. Painting started
5. Painting stage-2 and clearcoat
After one more round of clear coat on the front side, work on the front-side will be done 🙂
However, some slow work is in progress (by my friend) for finishing the EXAR 400 waveguides I had printed last year.. 🙂
1. Petals (printed in ABS) glued and lightly sanded
2. Primer coating
3. Puttied
4. Painting started
5. Painting stage-2 and clearcoat
After one more round of clear coat on the front side, work on the front-side will be done 🙂
That looks really nice.
Well you are in better shape than I was... during my career I basically walked away from audio for 20 years... there was just no time for it.
I DIYed a speaker in '68 or '69 and didn't do another until 2011...and it wasn't because that first one was so good
I had a hiatus of diy for 30 years...
Fortunately during that time we got internet forums, dsp and freeware REW!
Fortunately during that time we got internet forums, dsp and freeware REW!
Yes - I remember doing frequency response measurements and primitive circuit simulation in 1992. Here I am quoting myself from a post I wrote back in 2019...
Measuring Response in the Old Days
Back in 1992, making a frequency response curve was no easy task in a DIY situation but at least it was possible. There were test CDs which had 1/3 octave warble tones and 1/3 octave filtered pink noise. The MiteyMike was an accurate near-lab-grade microphone which could be attached to a camera tripod. I bought a true-RMS volt meter used in the telecom industry with a response from 10 hz to 100 kHz.
To make a response curve, I would start with 20 Hz, play the appropriate test CD track, set the pre-amp volume control to 2 V, and record the voltage generated by the microphone. By “record” I mean with a pencil, on real paper. Without touching the volume control, repeat the process for the next track at 25 Hz. Then at 32 Hz. Repeat 28 more times. I was fortunate enough to have access to a PC, so I loaded the recorded voltages into Excel, converted them to dB, and plotted them… if you did not have access to a PC or Mac, you did the calcs with a calculator and plotted by hand on log-linear graph paper. Having completed the on-axis measurements, I moved the microphone to the 30 degree off-axis position and repeated. Repeated again for 45 degree off axis. Repeat again for vertical dispersion… Etc. etc. etc.… It took hours to fully measure the response of one driver.
Measuring Response in the Old Days
Back in 1992, making a frequency response curve was no easy task in a DIY situation but at least it was possible. There were test CDs which had 1/3 octave warble tones and 1/3 octave filtered pink noise. The MiteyMike was an accurate near-lab-grade microphone which could be attached to a camera tripod. I bought a true-RMS volt meter used in the telecom industry with a response from 10 hz to 100 kHz.
To make a response curve, I would start with 20 Hz, play the appropriate test CD track, set the pre-amp volume control to 2 V, and record the voltage generated by the microphone. By “record” I mean with a pencil, on real paper. Without touching the volume control, repeat the process for the next track at 25 Hz. Then at 32 Hz. Repeat 28 more times. I was fortunate enough to have access to a PC, so I loaded the recorded voltages into Excel, converted them to dB, and plotted them… if you did not have access to a PC or Mac, you did the calcs with a calculator and plotted by hand on log-linear graph paper. Having completed the on-axis measurements, I moved the microphone to the 30 degree off-axis position and repeated. Repeated again for 45 degree off axis. Repeat again for vertical dispersion… Etc. etc. etc.… It took hours to fully measure the response of one driver.
go back far enough and they were calculating box sizes and crossover component values with slide rules
Work on the horns is done (atleast for now).
I can't wait to measure them and hear them and compare with the KVAR horns that I have 😀
Once they reach home, I will try to take measurements with 2 drivers.
1) BMS 4550
2) SB Audience Rosso 65CDN-T with a 1.4inch to 1 inch driver throat insert
Now need to start making boxes for 2 x 15drivers per side.. 🙂
Final pics of the horn
I can't wait to measure them and hear them and compare with the KVAR horns that I have 😀
Once they reach home, I will try to take measurements with 2 drivers.
1) BMS 4550
2) SB Audience Rosso 65CDN-T with a 1.4inch to 1 inch driver throat insert
Now need to start making boxes for 2 x 15drivers per side.. 🙂
Final pics of the horn
The color is gorgeous and the sections look like facets carved into gemstones now. Bravo
We’re all aware the horn matters so let’s see how it does on a CD or Tractix
Looking good. Waiting for the measurements.Do you still have the peerless CD?
Oh that brings back memories of the golden days.
That Panasonic electret condenser and the Mitey Mike / II:
Reference:
https://sites.pitt.edu/~szekeres/mic/mic.htm
And using Stereophile 1/3 octave warble tones on CD…
This was even before the soothing sounds of dialup:
I stepped away for about 10 years and along comes SpeakerBoxLite, VituixCAD and REW.
Software speeded up so many processes!
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