Audax ap210 with Kef t27 tweeter

[fin1bxn]

I was just looking at this combination in WinIS and I can get flat to 35k with a 90 litre cabinet. 38in high 12in wide 15in deep.

My question is I want to stay Tall and narrow or is a wider cabinet better? or narrow and deep. I dont mind going 17 deep.

Any sugestions with this combo....I won the t27 tweeters and i'm looking for a project.

Also I'm looking for simple crossover to go with these.

Thanks
Bob

 

[Inductor]

My question is I want to stay Tall and narrow or is a wider cabinet better? or narrow and deep. I dont mind going 17 deep.

Old versions (vintage) cabinets were large (front panel) what would have a good reinforcement of the base line.

 

[Inductor]

Hi fin1bxn,
Are you expecting to do a 2-way with those two?
Can we have a little of History here.
I know everybody like's the LS3-5, BBCs and Rogers, but why did you choose that woofer to work with a 1200Hz Fs (limits between 1.0/1.45KHz resonant frequency for T27)?
It may work or not depending on the "machine" you have in your hands.

 

[pinkmouse]

The AP210 has a lot of nastiness going on at around 2Khz, so I would be looking to cross over at least an octave lower, around 1Khz. Does the T27 go that low? I can't remember.

 

[fin1bxn]

Looking for 2-way

What happened is I had these T27 from a pr of Tangent RS2's. One woofer is gone and I have benn looking for about a year to find one..I cant. It was an AUdax 8" with a inverted surround. Needless to say I want to build a 2-way with the T27's. I havent purchased the audax yet. I have the RS2 cabinets and can use them they are about 15 litre or I can build someting better.....or bigger and better.

I figured the audax was the original matching woofer so I would stay with them...

Any help or sugestons are welcome...Basically just looking for something to build with those tweeter's.. I listen to alltypes of music and have Hi current hi power amps or Tube/s PP or SET.

Thanks
Bob

 

[Jonathan Bright]

Re; cabinet width. Generally speaking a narrow front, and by that I mean 12 inches or a bit less, will tend to give better dispersion and better stereo imaging according to the BBC work. I think Harwood (BBC Research) suggested that there might be a law of diminishing returns that failed to yield great improvement if made too narrow.

"Simple Crossover" The T27 often was used with a simple 3rd order network. This was a pair of 4.7uF caps with an inductor of around 0.25 mH between their junction and ground. That of course is the "minimalist" 3rd order possible. But in the mid '70 between the release of the KEF 104 and KEF 104ab they (KEF) made the xover quite a bit different with significantly better audible results. Martin Collums book "high performance loudspeakers" details the changes. So it might not be wise to worship at the feet of simplicity for its own sake with this one.

Pink mouse. The T27 has a resonance at about 1,200c/s. Never seen them used below 3k.

 

[Inductor]

Re; cabinet width. Generally speaking a narrow front, and by that I mean 12 inches or a bit less, will tend to give better dispersion and better stereo imaging according to the BBC work. I think Harwood (BBC Research) suggested that there might be a law of diminishing returns that failed to yield great improvement if made too narrow.

<<The cones of the Audax drivers are made of a special material called HDA (High Definition Aerogel) which is created by mixing carbon and kevlar fibres with an acrylic gel. This produces an almost-optimal material for a speaker cone with good internal damping and light mass. This particular driver was chosen since it was used in Dick Olsher's Poly Natalia speaker...

...The New Design

After extensive listening, I still wasn't happy with the sound which the design was producing - the reasons for which only recently became clear on the Madisound forum (apparently, the HDA drivers don't like narrow baffle designs, and need a lot of room around them inside to function well, with attention being paid to the back wave path). The general consensus on the basslist seemed to be that an 8" mid/bass was usually too large for a quality 2-way design (excepting a few rare cases), so I decided to move to a more compact design using a smaller mid/bass. >>
http://www.tbrowne.demon.co.uk/comp/projects/spkdesign.htm

fin1bxn TAKE CARE OF THIS NOTICE AT THE SAME SITE,
(THAT'S THE DRIVERS YOU NEED)
<<<Drivers For Sale

Since I don't strictly need the HM210Z0 drivers anymore, I'm willing to sell them for 100 quid - that price includes Interlink delivery and ~4m worth of QED Qudos Silver.>>>
Ps: Updated in "2000", probably they are gone now.

 

[Inductor]

You maybe would like to buy those woofers you mentioned, Audax AP210Z0.
For the price they cost it deserves to "super" experiment them, I would give a try. Those Kefs are used to work on the 3K-3K5 zone. Maybe a xover like this will do the job.

Other 8" drivers I runned across are
VIFA P21W0-20-08
VIFA P21W0-39-08
VIFA M21W0-39-08
AUDAX HT210G2
AUDAX HP210G0
AUDAX HM210G6
AUDAX HM210C0

DN Xover@2K4Hz