Quad amped actually 
Thanks to the two Hypex AS2.100 units. These class D amps contain two 100 watt @ 4ohm amplifier channels as well as a DSP board per unit. There is a master unit with volume control and input channel selector (SPDIF, USB and Analogue), and a slave unit which gets its data via the SPDIF in, from the Master's SPDIF Out. Very versatile!
Thanks to the two Hypex AS2.100 units. These class D amps contain two 100 watt @ 4ohm amplifier channels as well as a DSP board per unit. There is a master unit with volume control and input channel selector (SPDIF, USB and Analogue), and a slave unit which gets its data via the SPDIF in, from the Master's SPDIF Out. Very versatile!I thought I'd share the filtered response I ended up with.
My measurements showed that the alpairs have a slightly raised response in the 500-2500hz region. While this produces very clear vocals, I felt the region above 3000hz was a tiny bit too rolled off. when listening off axis (15-20 degrees).
Here's the Alpair 7.3's 1/24db smoothed response on axis, without filter:
unfiltered:
You can see the elevated response between 2500 and 500 hz. I did a Q=1 cut centering on 1200hz with a -1.3db gain to get this region level with the 3000-10000hz region. I nothed the 6Khz bump and the 10khz region slightly (Q=8, -2db gain for both) to tailor the high frequency response to my liking. The unfiltered response is a bit too pronounced in this region I feel. I now have a very good balance between off axis "air" and non fatiguing highs in my room (which is quite "hard"). I changed nothing above 10.000hz. I finally low-shelved the region between 200-600hz to compensate for a slight the baffle step loss. I ended up settling on these parameters: center freq. 455hz, Q=0.71, 1.7db gain.
The resulting Alpair 7.3 response looks like this:
Not shown in the plots is the final adjstment I made a bit later: I boosted the 1630hz (cone edge difraction?) dip by 2.8db @ Q=7. I did not expect this to work out well as best practice dsp rules generally tell you not to boost but only to cut, but it did work out very nicely indeed.
I am crossing the Alpair 7.3 to the L26Roy at 200hz with a RL4 slope. The Alpair is delayed by 405ms for time alignment. Because the drivers are well withing a quarter wave of eachother @200hz the combined response is seamless.
I used REW to get an idea of the problem frequencies in the 20-100hz region. I notched at 30 and 60 hz (Q=8, -3 and 4 db respectively), and reduced the output in the 70-100hz region slightly.
The resulting performance is very, very good to my ears. I notice the urge to keep tweaking is gone. Always a good sign.
My measurements showed that the alpairs have a slightly raised response in the 500-2500hz region. While this produces very clear vocals, I felt the region above 3000hz was a tiny bit too rolled off. when listening off axis (15-20 degrees).
Here's the Alpair 7.3's 1/24db smoothed response on axis, without filter:
unfiltered:
You can see the elevated response between 2500 and 500 hz. I did a Q=1 cut centering on 1200hz with a -1.3db gain to get this region level with the 3000-10000hz region. I nothed the 6Khz bump and the 10khz region slightly (Q=8, -2db gain for both) to tailor the high frequency response to my liking. The unfiltered response is a bit too pronounced in this region I feel. I now have a very good balance between off axis "air" and non fatiguing highs in my room (which is quite "hard"). I changed nothing above 10.000hz. I finally low-shelved the region between 200-600hz to compensate for a slight the baffle step loss. I ended up settling on these parameters: center freq. 455hz, Q=0.71, 1.7db gain.
The resulting Alpair 7.3 response looks like this:
Not shown in the plots is the final adjstment I made a bit later: I boosted the 1630hz (cone edge difraction?) dip by 2.8db @ Q=7. I did not expect this to work out well as best practice dsp rules generally tell you not to boost but only to cut, but it did work out very nicely indeed.
I am crossing the Alpair 7.3 to the L26Roy at 200hz with a RL4 slope. The Alpair is delayed by 405ms for time alignment. Because the drivers are well withing a quarter wave of eachother @200hz the combined response is seamless.
I used REW to get an idea of the problem frequencies in the 20-100hz region. I notched at 30 and 60 hz (Q=8, -3 and 4 db respectively), and reduced the output in the 70-100hz region slightly.
The resulting performance is very, very good to my ears. I notice the urge to keep tweaking is gone. Always a good sign
.
Last edited:
I heard these on a DIY listening day here in the Netherlands, last week. This is a day where people from all over the Netherlands and the Dutch-speaking part of Belgium come together. Some of the best DIY stuff from this region is there, from all budget ranges. There was even someone there that had made his own drive units. (I was the one with the beard, playing reggae and classical music on everybody's systems. )
Anyway. These speakers had beautiful tone and space. Lots of low-level detail, both in terms of timbre and detail. We switched between different loudspeakers, particularly a well-made multiway with "exotic" components and tube amps. There were obvious differences in sound, but they were both very good at playing music. I would need to take both home and listen to them for a while, play lots of recordings, to say which one is a more exact reproducer. I think that shows how close they were.
I was very happy with the experience. I love fullrange drivers, that "certain something" that they offer more than multiway speakers. I am also a hobby musician, listen to a lot of live performances and appreciate that "certain something" that multiway speakers do a little better. I have heard many FAST's not doing either very well. Fortunaly, Swifty did an axcellent job and these perform very, very well!
)Anyway. These speakers had beautiful tone and space. Lots of low-level detail, both in terms of timbre and detail. We switched between different loudspeakers, particularly a well-made multiway with "exotic" components and tube amps. There were obvious differences in sound, but they were both very good at playing music. I would need to take both home and listen to them for a while, play lots of recordings, to say which one is a more exact reproducer. I think that shows how close they were.
I was very happy with the experience. I love fullrange drivers, that "certain something" that they offer more than multiway speakers. I am also a hobby musician, listen to a lot of live performances and appreciate that "certain something" that multiway speakers do a little better. I have heard many FAST's not doing either very well. Fortunaly, Swifty did an axcellent job and these perform very, very well!
Thanks for the nice words!
@ gurpreetsingh: Unfortunately I do not have any plans or drawings for these. To make the roundover I used a circle with a radius of 20cm, the angle of the speakers is 5 degrees, the height is 92cm total, the depth is 37cm. i used 24mm birch ply for the sides and 18mm MDF for the middle 8 "slices". The rest you should be able to figure out from the pics in this thread.
Good luck!
@ gurpreetsingh: Unfortunately I do not have any plans or drawings for these. To make the roundover I used a circle with a radius of 20cm, the angle of the speakers is 5 degrees, the height is 92cm total, the depth is 37cm. i used 24mm birch ply for the sides and 18mm MDF for the middle 8 "slices". The rest you should be able to figure out from the pics in this thread.
Good luck!
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.