Kjeldsen OB model 2

I'm in the test mode with my new OB's

Inititally I will try some woofers. I had hoped for B2Audio 15 inch woofers, but they are sold out, so I bought one Gladen RS15FA to test in the mean time.

It's quite promising. This is just a mock up to feel the potential. Very simpel cross over and no eq at all. Capacitor on the Tangband full range and an inductor on the woofer. Crossed and just below 1 kHz. I can only play mono. I can add a little eq in Foobar, and get quite good results.

Measurement are in room as you can see. I am quite amazed that it measures so well down to 30 Hz. Subjectively I still miss some bass, but I only add 6 dB in Foobar, and som eq to linearise above 1 kHz. The result was much better than expected. I'm not sure I'll wait for B2audio to be in stock again.

The Gladen woofer is very silent and very well build. The price is also very nice.


  • Maaling 1 png.png
    Maaling 1 png.png
    76.7 KB · Views: 413
  • maaling 2.JPG
    maaling 2.JPG
    153.9 KB · Views: 417
Last edited:


2013-12-23 12:45 pm
Please post ant further findings in regard to the woofer.

I have been waiting for ages for someone to use the Gladen RS15FA in an open baffle.
Ever since I saw it being used by HifiAkademie in their DiPol speaker.

....::: HIFIAkademie.de :::....

I am myself toying with the thought of trying out a pair of dipoles for my studio. I have a pair or TB w8-1772 lying around that I'm thinking of using.

Were you planing on using two per side or a single one?

I assume that "good price" means in the 200 euro range.

well, keep us posted, dying to hear what you think.


Thanks for the link to HIFIakademie, I didn't see that. Acutally it's very hard to find anything on that woofer for domestic use.

I did plan to use two per side, but I am rather impressed with just one woofer, so I think it's enough. My next move is actually to try the slot loading that HIFIakademie is also using.

The woofer in Denmark is 175 €. For such a nice design and quality that is really a bargain.


2013-12-23 12:45 pm
Happy to being able to show some of you another type of dipole.
As I have gathered from german hifi forums the products of HifiAkademie seem to be held in high regard, especially their amps with built in dsp.

I myself don't really care for the "clinical look" of their speakers.

I word of caution. If I remember correctly the woofers in the DiPol15 are custom made, by Gladen, for that particular speaker.
In what way the differ I don't know. Seems to be working well for Kjeldsen.

Someone also pointed out that the HifiAkademie speakers are not strictly dipoles since the Tangband is protruding at the top of the baffle.
There are smarter people here who maybe can explain what effect this will have.

The HifiAkademie speaker is not strictly dipole. Dipole = figure of eight respons, and a full range driver simply can't do that.

On the HifiAkademie page, I can see that Linear Xmax is +/- 9 mm. I have been told from the Danish reseller (he got it from Gladen), that the RS15FA have Xmax of 15 mm = +/- 8 mm, but that is rather close. If it's custom made, I guess they might have chosen a bit lighter diaphragm.

The B2Audio have +/- 12,5 mm linear Xmax and +/- 25 mm Xmech, so this woofer can take a little more eq
Last edited:
I have done some more testing. If I need real deep bass, I need two woofers per speaker.
But for 40 Hz and above I would be happy with just one. I still haven't settled for type of OB yet. I don't think the SLOB I have tested is better than plain OB. I have tried plain OB with very big baffle - that is very good - but I dont't have the room for that. A U-baffle might be the next type I will test.