Alpair 10.3 FAST / WAW guidance needed

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So this is how they turned out, still lots to do but first soundtest very positive.

Crossed now at 80hz, need to measure to get them set correctly.

They kick like a mule. :)
 

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First adjustments and measurements done, not a small task to adjust phase, crossover and volume for all parts separately.

At least the sub part is now adjusted, thanks to Audyssey for fixing the 30hz bump.

Next step far & near field measures for all with REW. I think I'll test a higher crossover, now it's 80hz.
 

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So, measurements done and still happy with the results. Might try a little notch filter for the 5-10khz range, it does sound a bit bright but not annoyingly.

The sealed Alpair 10.3 measure down to 30hz -6db without subs but they are crossed over at 80hz to keep the 80-200hz area smooth.

All in all the total costs for the pair was around 500€ - 200€ for the plate amps, 200€ for the elements and 100€ for plywood & misc.

Now just need to finish the surface and prepare for painting.
 

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Finally proper(?) measurements and might want to try a notch filter for 5-10khz range.

Looking at the graphs, first one is individual speakers wo subs at 1m, second one both at listening position with 3 different angles (0-5-10 degrees inwards)

Filter calculator gives me a series filter with 0.2mH coil and 4.5uf cap, does that sound right?
 

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Or just listen off-axis.

dave

I'm already listening off-axis, but that still leaves the 5-10khz range around +5db. If I turn them away, that drops the 10-20khz too much down but 5-10khz doesn't go down much.

It's a trial, I might prefer without the filter but also looking to build my skills with speaker building and measuring. Doesn't hurt if sound improves as well.
 
Thank you, seems he had very similar measurements and the filter response was as calculated in measurements. Using a parallel filter seems smart so I can adjust the dampening just by changing the resistor if needed.

I played around with the calculator and I'll try first with
R:10 Ω C:9 μF L:0,05 mH

That should cut just between 5-10kHz as needed but let's see.
 
Today I learned two very important lessons:

1. Audyssey (my room correction) setting "Flat" corrects the WHOLE frequency range, regardless of any limitations set. This was messing with all my measurements, now I managed to set the crossovers and subs to pretty perfect combination.

2. The 5-10khz bump was caused by early back wall reflections. I accidentally did measurements with some clothes lying on the sofa back and poof - the bump was gone. So, instead of needing a crossover (already ordered, dammit) I need to add some light treatment to the back wall.

Live and learn, that's the fun part of DIY. :)
 

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Eric had a similar issue with his A10.3 in FHXL. You might check to see what filter he used.

dave

Eric ended up using a 0.27mH coil, with a 28R resistor, and a 1.47uF cap, all in parallel with one another. Then, he placed this network in series with the positive terminal of the speaker (private correspondence).
 
Here's the measurements from listening position with the crossover. It does exactly what I wanted it to do, which is quite a suprise considering my complete noviceness.

Subs also adjusted, now giving decent response to 15hz, still room for adjustments but need to focus on listening for a while, the new album from Tool is sounding brilliant!
 

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Sure. It has been done. And even more with the A7.3.

There is a wealth of designs yet to be explored in WAWs.

Pick a good woofer that you can get (& afford), is sensitive enuff for your needs, and will fit in a box that suits you, then add a good FR.

dave
can we use a subwoofer like for example Iwai Electronics Pvt. Ltd.
and use alpair 7p on top of it (sealed/ported).
 
can we use a subwoofer like for example Iwai Electronics Pvt. Ltd.
and use alpair 7p on top of it (sealed/ported).

At a glance looks reasonable but you should simulate with Winisd or similar. With a smaller fullrange as 7.3 you might want a woofer that is crossed over higher (120-150-200hz) so sound quality is a big point, it was already pointed out.

In my build crossing over any higher than 80hz makes the sound weird due to different tonal qualities, I don't know if the side facing woofer is also to blame. Could also be that the woofer signal is mono so the stereo image starts to lose focus. Which is a shame because I would prefer crossing over a little higher to level out the frequency response.

80hz is fine for the sealed 10.3 in my room as I get almost 30hz out of them with room gain. That down I don't notice any tonal difference, the response sounds balanced.
 
frugal-phile™
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i am very careful using subwoofers on the bottom. They most often do not do very high and are hard to integrate with the FR.

If you go the subwoofer route i’d suggest 2 x 8 or 2 x 10 (loaded push-push) on each side. Watch for a decent HF response (out to 1k is probably good, i usually look for at least an octave higher — the one you linked gets ugly above 500KHz). You will likely have to XO lower with a subWoofer.

Everything is a set of compromises. You have to choose the set that best suits you.

The A7p can be used as far down as about 105 Hz (sealed ~5 litre) and use the rolloff as 2 poles of your filter. Personally i like a midTL and an XO at least an octave higher.

Where you roll-off should also be driven by where the bafflestep F(-3) is.

I consider subwoofers to be used below the midBass (ie less than 50-60 Hz, ie make it a 3-way), but i have a scheme in my head for something far trickier than most (haven’t found anyone yet that describes exactly what i want).

dave
 
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