Hello, I’d like to start my first DIY speaker project. I have two Dynaudio D28AF (8 Ohm) and two Dynaudio 17W75XL (4 Ohm) drivers and would like to design and build a bookshelf speaker with them. It would be great if someone could share ideas for the enclosure and crossover, or perhaps point me to a Dynaudio design plan for these drivers and provide the schematics.
Ran the T/S data provided by Dynaudio with a sum check for any Red flags.
No immediate red flags seems straight forward. It has been rounded up, not bad
Can still get a alignment.
Trends Towards 4th order so standard BB4 or C4 would tune At 40 Hz (BB4) or for C4 slightly below 39 Hz
Volume 19.2 to 14.3 liters. So datasheet showing 15 liter cabinet used seems reasonable.
They do tune high to a obnoxious high Q by going 13 Hz above Fs. For typical fake bass bump.
Low levels ok, high levels it is baked in. So for bass adjustment just use EQ. The fake bake is built in cant be changed.
It will just unload the system faster. Better to just use standard alignments.
I will show you data sheet Q
And also show you standard 4th order alignments for this driver.
Datasheet = Red (fake bake high tuned)
Standard alignments
BB4 = Orange 14.4 liters 40 Hz Fb
C4 = Yellow 19.3 liters 39 Hz Fb
C4 looks more than good to me.
No immediate red flags seems straight forward. It has been rounded up, not bad
Can still get a alignment.
Trends Towards 4th order so standard BB4 or C4 would tune At 40 Hz (BB4) or for C4 slightly below 39 Hz
Volume 19.2 to 14.3 liters. So datasheet showing 15 liter cabinet used seems reasonable.
They do tune high to a obnoxious high Q by going 13 Hz above Fs. For typical fake bass bump.
Low levels ok, high levels it is baked in. So for bass adjustment just use EQ. The fake bake is built in cant be changed.
It will just unload the system faster. Better to just use standard alignments.
I will show you data sheet Q
And also show you standard 4th order alignments for this driver.
Datasheet = Red (fake bake high tuned)
Standard alignments
BB4 = Orange 14.4 liters 40 Hz Fb
C4 = Yellow 19.3 liters 39 Hz Fb
C4 looks more than good to me.
***Note
Good note to be taking due to correctional error factors involved with port calculation, in sim opposed to real life.
The impedance curve shown in the datasheet does not indicate a high Tuning of 53 Hz
The datasheet shows closer to 43 to 47 Hz.
My goal as a builder would still be towards standard 39 to 40 Hz port length calculation.
With expected rise in Fs from voice coil temp.
Standard error correction for no shared walls .732
If the port is mounted closer to a wall or boundary can climb to .850 to 1
If sharing 3 walls as a typical slot port can climb to 2.27
Plain English the port appears longer or tuning is lower when closer to boundaries, or sharing walls appears even longer.
Good note to be taking due to correctional error factors involved with port calculation, in sim opposed to real life.
The impedance curve shown in the datasheet does not indicate a high Tuning of 53 Hz
The datasheet shows closer to 43 to 47 Hz.
My goal as a builder would still be towards standard 39 to 40 Hz port length calculation.
With expected rise in Fs from voice coil temp.
Standard error correction for no shared walls .732
If the port is mounted closer to a wall or boundary can climb to .850 to 1
If sharing 3 walls as a typical slot port can climb to 2.27
Plain English the port appears longer or tuning is lower when closer to boundaries, or sharing walls appears even longer.
There are still original Dynaudio kit references around on the net, albeit maybe not all in English and maybe not so easy to find - try this link (it's in Dutch, but should translate reasonably well through google translate), and references therein. There might be something of interest - you may need to try retrieving info via Internet Archive etc. (gattiweb.com esp.) - I have copies of some of the older kit plans, but certainly not all. Personally, I use a set of original Dynaudio 'Pentamyd' bookshelf (kit) speakers, built for me back in the mid-80's (but not to the original Pentamyd cabinet design).
https://zelfbouwaudio.nl/forum/viewtopic.php?t=8546
https://zelfbouwaudio.nl/forum/viewtopic.php?t=8546
Hello new here, but in searching information about Dynaudio products, this post reflects something similar I have.
Dynaudio 17W75 and D28AF, in a sealed 18 liter enclosure with a Madisound design12 dB woofer roll off and 18dB tweeter in a Butterworth configuration. 8 ohm. That's from memory as I purchased these components in 1988. I paired this with a DIY 12" subwoofer with 120 HZ active crossover driven by a Hafler 150 W amp. and the Dynaudio build driven by a Carver receiver. The Dynaudio speakers sounded very nice for many years enjoyment.
The link to the Dutch website is very useful and the Rigoletto is similar to mine. I was going to design my own crossover, at the time was very active i DIY speakers. My friend and I built a pair, in a truncated pyramid sealed cabinet and the imaging was excellent.
Good luck with your build!