Super-Tysen

[buzzforb]

Dave,
I have been reading threads about your Tysen speaker and came across a post that suggested you were working on an SDX7/Alpair 7 combo. Did you ever finish that speaker as I am very interested in using an ALpair7 or 10.2 in this type of enclosure as my first speaker. Side note: Not knowing much about speakers, why have you chosen side firing woofers? THanks.

 

[planet10]

I still haven't finished designing it yet. I have a number of preliminary drawings, but am not yet satisfied with what i have come up with so far.

dave

 

[buzzforb]

why the side firing woofer? Is it because it is crossed low and down low the woofer is firing into 4pi space and directivity is not an issue? Does adding a woofer and freeing up the Alpair from going low improve the response/sound of the Alpair because of reduced excursion? forgive me if these are not the right terms? I have followed many of your threads and need help as i am going to purchase one of the two Alpairs mentioned now that they are available.

 

[planet10]

At the frequencies the woofers are used in, they are omnidirectional. Side firing means i can get them closer to the mid-tweeters, creating, in essence, a large co-axial loudspeaker.

Yes, relieving A7(s) from low bass improves their mid-top performance.

dave

 

[buzzforb]

Is the chamber of the woofer seperated from thr FR? If not, wont it affect the FR from inside the cabinet. Based on a 16' X 16' room, should I go with 10.2 or 7?

 

[planet10]

Yes. Woofers have there own (common enclosure). I'd like to get the A7(s) into their own little TLs, that is proving tricky.

dave

 

[buzzforb]

If sealed and radiating into 4pi space, what is the need for attempted coaxial location, better phase coherence? Also, I read an article from Olsher saying that he did not like the idea of using drivers with different cone material. What is your opinion. I found this 8" Audax woofer with more efficient SPL response, Would it work as well as SDX7. Seems to have more even response curve as well.

https://www.madisound.com/store/product_info.php?cPath=45_228_257&products_id=8930

 

[planet10]

The closer together all the sources, the better.

There probably is something to the common cone material idea, but, once tweeked, the SDX7 works really well.

I am sure that there are a lot of good mid-woofers that can serve the same role as the SDX7. I have some Silver Flute here as well to play with -- and the Mark Audio #6/EL166 works well in another project.

dave

 

[buzzforb]

Thank you for the info and the time. One last question, between the 7 and 10.2 in this configuration, which will be able to play a greater range of music. Which would you choose from your experience. I know you havenmt played with the 10.2 much, but you have as good of an idea of its ability as anybody. I guess that was more than one question!

 

[planet10]

Actually i have played with A10.2 (we got a hand built set of production prototypes for diyFEST), but not as extensively as A7. ATM, with bass support, i'd be choosing A7.

dave

 

[buzzforb]

Mucho gracias! Would rounding over the leading edge of the box help with baffle rolloff. The woodworking part will be easy for me! If Santa is good to me at work, perhaps i can have a pair of Alpair 7eN's.

 

[planet10]

Would rounding over the leading edge of the box help with baffle rolloff.

As per Olson Page 23, the bigger the roundover/bevel, the smoother the 2pi to 4pi transition. As well they help reduce edge diffraction higher up.

dave

 

[buzzforb]

Where can I find this book.

 

[planet10]

The book is Olson's Acoustics. I think audioXpress sells a reprint. One of the bibles.

Page 23 has been posted so many times i thot you might already have seen it... i'll see if i can trawl up a link.

dave

 

[buzzforb]

I am pretty sure I have come across it before, but I have been digesting so much info the last couple of months, specifics get blurry sometime. Thanks for the help!

 

[planet10]

 

[buzzforb]

To implement these different shapes, does the driver circumference have to stay in proportion to the drawn sizes. That looks like a 1" hole, so for a 4" driver, the baffle would be huge. I find it interesting that the spher does not do as well as the chamfered baffle.

 

[tomchr]

The book is Olson's Acoustics. I think audioXpress sells a reprint. One of the bibles.

Dave, do you know the year it was published?

~Tom

 

[planet10]

To implement these different shapes, does the driver circumference have to stay in proportion to the drawn sizes

The baffle scales up/down with decrease/increase in baffle & champher/roundover size.

What has been charted is but a small sample set of points in "baffle/box shape" space and define behavoiur at that point. Interpolation is required for more practical shapes.

davve

 

[buzzforb]

Interpolation is required for more practical shapes.

davve

You had to throw in a new twist, didn't you. I will be investigating this today. On the Tysen design, do i stand to gain anything by executing a dipole, or is it bipole, with the A7. I know i get increased SPL, but is their any other benefit? What is to be gained from a larger enclosure? Sorry about all the questions. I know you guys "in the know" probably get tired of answering them. The forum is so vast it is really time consuming trying to weed though everything.