Hi,
I'm building a FAST system with two tapped horn subwoofers and four full-range speakers. The 4 FR speakers are paired up in the same room (a fancy kitchen) pointing at two different listening areas. One toward the cooking area, the other at the table. The FR's will be as small as possible (15-30L), wall mounted, close to the ceiling and pointing down. The crossover is a DSP with up to 48dB/oct slope capability. The TH range is 33Hz-115Hz. The FR's I'm trying to choose between are 8" TB W8-1772 or W8-2145. So I will have to set the XO quite low, which means the FR's will have more to work on in LF. Both FR options roll-off around 90Hz but one is vented with a QB3 alingment, the other is closed. My question is: Should I choose a vented alignment with a port resonance peak at the lower end of the crossed over frequency range of the FR? Ie say the XO freq is 90Hz with a very steep roll-off, could the port resonance be around 100Hz so as to limit cone movement at the lower end to reduce IMD or doppler effects that muddy up the mid and high frequencies? Or would it be ok to just use a closed box?
Best,
Selim
I'm building a FAST system with two tapped horn subwoofers and four full-range speakers. The 4 FR speakers are paired up in the same room (a fancy kitchen) pointing at two different listening areas. One toward the cooking area, the other at the table. The FR's will be as small as possible (15-30L), wall mounted, close to the ceiling and pointing down. The crossover is a DSP with up to 48dB/oct slope capability. The TH range is 33Hz-115Hz. The FR's I'm trying to choose between are 8" TB W8-1772 or W8-2145. So I will have to set the XO quite low, which means the FR's will have more to work on in LF. Both FR options roll-off around 90Hz but one is vented with a QB3 alingment, the other is closed. My question is: Should I choose a vented alignment with a port resonance peak at the lower end of the crossed over frequency range of the FR? Ie say the XO freq is 90Hz with a very steep roll-off, could the port resonance be around 100Hz so as to limit cone movement at the lower end to reduce IMD or doppler effects that muddy up the mid and high frequencies? Or would it be ok to just use a closed box?
Best,
Selim
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This is more a sunBoofer/satalitte system than what fits into the typical WAW range and should get somewhat different approach to placement.
15-30 litres is not small, i was thinking 2.5-5 litres when i saw small. *” is also likely way to large for the application. How loud do you have to play these?
dave
15-30 litres is not small, i was thinking 2.5-5 litres when i saw small. *” is also likely way to large for the application. How loud do you have to play these?
dave
15 litres is small when we are talking about the W8-1772 !
But Dave raises a good question... How loud and how dynamic do you need your kitchen speakers to be?
Most of the time, in my kitchen anyway, it would be elevator music levels, where you kinda lose the bass.
Having 8" drivers means beaming, so you will get higher frequencies right at the spot the speakers are aiming, but will drop very quickly as you move around the kitchen.
I would look into some coax drivers instead, staying with TB, like the W6-2313.
And since you have dsp, you can put them in a sealed enclosure and boost the low end a bit to reach your subs.... But again, will you have many rave parties in your kitchen?
But Dave raises a good question... How loud and how dynamic do you need your kitchen speakers to be?
Most of the time, in my kitchen anyway, it would be elevator music levels, where you kinda lose the bass.
Having 8" drivers means beaming, so you will get higher frequencies right at the spot the speakers are aiming, but will drop very quickly as you move around the kitchen.
I would look into some coax drivers instead, staying with TB, like the W6-2313.
And since you have dsp, you can put them in a sealed enclosure and boost the low end a bit to reach your subs.... But again, will you have many rave parties in your kitchen?
Thank you Dave. Yes, you're right. Here's what I'm trying to achieve: A friend who listened to a pair of Kirishimas and a pair of tapped horns I had built for another friend, asked me to build something similar for his kitchen. He fell in love with the FR sound stage playing jazz and the THs sound with techno . During dinner parties he'll play jazz etc at low levels and if the dinner turns into a full blown party, he wants to entertain guests with dance / electronic music played at loud levels. The Kirishimas paired with TH's do both really well IMO. So I tried to design a similar system.
I agree. I should have said, "as small as possible". When his guests get enough to drink, they will be played quite loud. Since the TH's I designed have a low BP, I wanted to pick larger FR's that can handle frequencies down to about 100hz.
Thank you Perceval. I can make the cooking area speakers closer to 30 liters which seems enough for QB3 alignment for the W8-1772, because there is more room there, where the louder sound is more appropriate when the party's going on. The dining area requires much less sound, so smaller divers and cabs can be more appropriate. For that I thought of using a sealed enclosure to reduce the size.
Most of the time, in my kitchen anyway, it would be elevator music levels, where you kinda lose the bass.
I'm also a bit worried about beaming at the dining area, which will mean people at the edge of the table will have a different experience than the ones sitting in the middle. But at the same time beaming would mean less early reflections? Beaming may not be such a big issue for the cooking area. You got me thinking.
I would look into some coax drivers instead, staying with TB, like the W6-2313.
Good idea. I thought about it briefly but I couldn't find a ready crossover that would work with them and I wasn't sure about their sound. Do you have any recommendations?
For a coax that seems the way to go. But the coax's roll off maybe way above where the TH's XO rolloff (around 85 hz) has to be. BTW, the speakers on each channel will be wired parallel. So no zone control.
I think he might have a few really loud parties. 🙂
Sorry for the formatting of the posts.
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Alright then.
Loud kitchen parties!
Where I come from, Quebec, the kitchen is a very social place.
I've done an XO for the W6, and it looks like they would match your TH.
Here:
TB new line of Coax FR drivers
Loud kitchen parties!
Where I come from, Quebec, the kitchen is a very social place.
I've done an XO for the W6, and it looks like they would match your TH.
Here:
TB new line of Coax FR drivers
Thank you Perceval. The kitchen isn't a regular household kitchen. It's an open plan area with a bar on the other side of the countertop and a dining area that can seat about 12 people. I just had a look and the drivers are 4 ohm. 🙁 Which means I can't wire them in parallel for the two zones. (The amp can do 4 ohm min.) If I wire them in series, I'll have half the power. Any other suggestions?
If I have to go the FR route, would it make sense to go vented with a resonance around 100-150Hz to limit cone excursion, so as to minimize IMD and doppler distortion?
If I have to go the FR route, would it make sense to go vented with a resonance around 100-150Hz to limit cone excursion, so as to minimize IMD and doppler distortion?
The W6 can do 100-150 Hz in a sealed box. I have them playing in a rather large room right now, while I'm tweaking another set, and they are fine when supported by a sub at about 100-ish Hz.
Actually would make sense to have two amps... one for the dining room area, and one for the kitchen, so you would have better control over the sound pressure in different areas.
Plenty of good amps these days... from the cheaper D class little ones, to the more esoteric.
I have the feeling your friend wouldn't mind showing off a couple of nice amps.
So, you could have the kitchen area dancing while the dining area more about discussions with music in the background.
Actually would make sense to have two amps... one for the dining room area, and one for the kitchen, so you would have better control over the sound pressure in different areas.
Plenty of good amps these days... from the cheaper D class little ones, to the more esoteric.
I have the feeling your friend wouldn't mind showing off a couple of nice amps.
So, you could have the kitchen area dancing while the dining area more about discussions with music in the background.
I don't know if you are in a hurry, but SBA is coming up with this....
8” SB20FRPC30-8 / Paper – Sbacoustics
sealed F3 is 64Hz in 30-ish litres
11mm Xmax, 92dB sensitivity, Fs=39Hz, 50W handling power... a beast of FR driver!
It will be on my list of things to buy and try for sure!
8” SB20FRPC30-8 / Paper – Sbacoustics
sealed F3 is 64Hz in 30-ish litres
11mm Xmax, 92dB sensitivity, Fs=39Hz, 50W handling power... a beast of FR driver!
It will be on my list of things to buy and try for sure!
Yes two amps would make a lot of sense. And my friend does like fancy equipment. But so far I've already stretched his budget with a sub amp, a Dirac etc. So going the FR route might be the only way if I can't find a suitable 8 ohm coax alternative. The SBAcoustics specs look really good. I'm going to order one when it comes out. But I only have three weeks left to make the system. Please let me know if you think of any other solution.
What do you think about vented vs closed in terms of cone excursion close to the XO point? Would it make sense to let a vent take care of those frequencies around 100Hz? Any benefit to that you think? Dave, I would appreciate hearing your thoughts on this as well.
What do you think about vented vs closed in terms of cone excursion close to the XO point? Would it make sense to let a vent take care of those frequencies around 100Hz? Any benefit to that you think? Dave, I would appreciate hearing your thoughts on this as well.
If you can live with the higher frequency at which the FR is still useful, sealed is generally better than vented. If there is even more margin there i like aperiodic midTLs.
dave
dave
I like sealed too, especially if there are chances of spirited sessions!
Sealed will control the cone better, and will limit group delay.
You could save some money by not going Dirac, and getting a miniDSP product. You'd get he splitter, EQ on all channels, and FIR filters with a little more work.
Dirac is easier of course, but also a "one recipe fits all" kind of thing.
It's not bad, but if someone is willing to work a bit more, it's possible to get better than that.
I do understand that time is sometimes limited.
TB makes other FR drivers, 5 and 6", but they have beaming issues that is more or less pronounced depending on the driver.
I like the 3" and 4" Faital FR, they have very good sensitivity, can handle power, but because of their size, they won't provide the low mid oomph needed for techno.
Although, you could put a 4" Faital in a TABAQ, attach it side ways on the ceiling. That might work. With some imagination, it could be integrated with the design of the kitchen.
They have 4, 8 and 16 Ohms versions.
Sealed will control the cone better, and will limit group delay.
You could save some money by not going Dirac, and getting a miniDSP product. You'd get he splitter, EQ on all channels, and FIR filters with a little more work.
Dirac is easier of course, but also a "one recipe fits all" kind of thing.
It's not bad, but if someone is willing to work a bit more, it's possible to get better than that.
I do understand that time is sometimes limited.
TB makes other FR drivers, 5 and 6", but they have beaming issues that is more or less pronounced depending on the driver.
I like the 3" and 4" Faital FR, they have very good sensitivity, can handle power, but because of their size, they won't provide the low mid oomph needed for techno.
Although, you could put a 4" Faital in a TABAQ, attach it side ways on the ceiling. That might work. With some imagination, it could be integrated with the design of the kitchen.
They have 4, 8 and 16 Ohms versions.
Great info. Thank you! I'll see if I can do something with the Faital 4". OK I'll start with a miniDSP and see where I get with that. I can always upgrade miniDSP to Dirac with a software upgrade if need be.
A short TL damped such that there is low density fill near the driver getting progressively more dense in an attempt to absorb the entire rear radiation. Done properly the impedance peak at resonance is greatly reduced and this makes a passive XO easier (or use of a current amp more appropriate).
Simpliest is something like a 4” D piece of PVC or cardborad pipe running out the back of the box. Tapering the line makes it even better.
Here you can see the implementation in Tysen V2. We use similar in the big MTM WAW. You can also fold the line to make the net box rectangular and the terminus out the front. Make the line long enuff and it can be made ½ wave (ie sealed). XRK’s dagger is a very small implementation.
And here (from Tysen V1) the change in impedance.
dave
I found the B&C 6HCX51 coax which goes down to 100Hz with a QB3 alignment with only 4 liters. I wonder if they're suitable for jazz etc.
Sorry, I do not have any experience with B&C.
Looks ok, but I think coming up with an XO for it will be a challenge, looking at their respective curves.
They are not cheap either.
Looks ok, but I think coming up with an XO for it will be a challenge, looking at their respective curves.
They are not cheap either.
I've read in the forums that people had good experiences with the B&C's in terms of subjective sound quality. I found some assembled XO's from parts-express, like the Dayton Audio XO2W-2K 2-Way Speaker Crossover 2,000 Hz or the Dayton Audio XO2W-2.5K 2-Way Speaker Crossover 2,500 Hz. Since its recommended XO freq is 2.2kHz.