butterworth filters? -- I do not like them on the dcx... to me, they sound bad crossing from sub to top, even with a large underlap.
And but48 for the HP? I could on this sub go down to 34hz HP, but choose not to. 38hzLR at 48 is what I like the sound of best.
so I guess to answer your question -- it's what I like.
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Re: oliver drawing 24x48x30_th_dims_short_s1_mod_s5.pdf,
- is this the latest jbell built?
- throat chamber Atc = round shape with woofer cone size?
- throat chamber port Ap1 & Lpt = round shape with L12 radius?
- any advantages of v-shape throat ala furybox applied to this?
Post #283
Hi panjilaras,
Post #163 was part of theoretical suggestions for Ben (salzburgsoundsystem) on what could be done with the dimensions of his already pre-cut wood (see: around Post #140). It's as far as I want to take this. I had a little extra time, now I'm back to normal, completely snowed under. In other words it is theoretical, untested, and further details are up to you.
Regards,
Hi panjilaras,
Post #163 was part of theoretical suggestions for Ben (salzburgsoundsystem) on what could be done with the dimensions of his already pre-cut wood (see: around Post #140). It's as far as I want to take this. I had a little extra time, now I'm back to normal, completely snowed under. In other words it is theoretical, untested, and further details are up to you.
Regards,
If anyone is interested I'm going to be running 4 of JBell's Large TH subs at the Gibralter Trade center in Mt. Clemens, Mi. Friday and Saturday nights from 9pm till 1am. June 18, 19 and June 25,26. Live band ROOM 13. in the 160' long X 60' wide pavilion. using a QSC PLX 3602 for the subs and the tops are powered QSC 15 and a horn. I will be making some tops when I get time and money.
I just used them for the first time this past Friday and Saturday at AUGIES in Madison Ht. Mi. I usually use 4 18" front load subs. the 18's have more punch within 10 to 15 feet from them and get lost after that. JBells subs are there at 10 to 15 feet but get better after that and stay strong all the way to the back of the room. I had them laying on there side center loaded. We'll see how they do at this next show. I will keep you all posted.
Thank you,
Shawn
I just used them for the first time this past Friday and Saturday at AUGIES in Madison Ht. Mi. I usually use 4 18" front load subs. the 18's have more punch within 10 to 15 feet from them and get lost after that. JBells subs are there at 10 to 15 feet but get better after that and stay strong all the way to the back of the room. I had them laying on there side center loaded. We'll see how they do at this next show. I will keep you all posted.
Thank you,
Shawn
And the other side of the pond, in Austria
My friend has screwed up one of the JBell subwoofers. Might be because he cleverly bridged the output of the amp I supplied (pre-set to 40HZ lo-cut). So instead of 450 Watts, the amp was able to supply 2000. I wish people wouldn't f+++ around with my gear, especially trusted friends.
It would appear that something is wrong, still getting bass, but with interesting distortion - not scraping, more like something is rattling. we will see when I take a look, see if the driver is loose - or maybe torn?
Gentlemen, place your bets:
1. driver is loose, needs screwing better onto baffle
2. driver (paper cone) is torn
3. driver spider is damaged
4. voice coil is damaged
5. something else is up the creek
So, I may be using just the one of these for now, bit of a shame!
Regards, Ben
My friend has screwed up one of the JBell subwoofers. Might be because he cleverly bridged the output of the amp I supplied (pre-set to 40HZ lo-cut). So instead of 450 Watts, the amp was able to supply 2000. I wish people wouldn't f+++ around with my gear, especially trusted friends.
It would appear that something is wrong, still getting bass, but with interesting distortion - not scraping, more like something is rattling. we will see when I take a look, see if the driver is loose - or maybe torn?
Gentlemen, place your bets:
1. driver is loose, needs screwing better onto baffle
2. driver (paper cone) is torn
3. driver spider is damaged
4. voice coil is damaged
5. something else is up the creek
So, I may be using just the one of these for now, bit of a shame!
Regards, Ben
My bet is that the voice coil is hanging loose like a slinky.
I'm not sure whether this is due to over-powering, over-exursion, or whether it's from putting long term power in at tuning frequency. My worry is that high power at tuning frequency means plenty of heat to disperse yet the coil is hardly moving. Maybe this cooks the ends of the coils as they're sitting outside of the gap?
Don't know the reason but that's how my Ciare 12SW in Walt's stepped horn died.
I'm not sure whether this is due to over-powering, over-exursion, or whether it's from putting long term power in at tuning frequency. My worry is that high power at tuning frequency means plenty of heat to disperse yet the coil is hardly moving. Maybe this cooks the ends of the coils as they're sitting outside of the gap?
Don't know the reason but that's how my Ciare 12SW in Walt's stepped horn died.
Perhaps it's time to have a thread that deals with suitable passive speaker protection for PA use (if there hasn't been one already). I'm working on a number of designs at the moment, including an interesting 6th order BP design for one of the new Dayton PA drivers, and I'll be pissed if after all that work the driver gets destroyed because some grummit didn't hook an amp up properly, or ignored the RMS power guidelines...
my bet is overexcursion, and the 40hz high pass was disabled....
Scott runs way past 450watts safely on his cabinets, but does so smartly. (48db/oct high pass)
No high pass = dead tapped horn driver.
BTW, xti's are wonderful for things like this... eq, crossover, high pass, limiter, PASSWORD PROTECTION.....
Scott runs way past 450watts safely on his cabinets, but does so smartly. (48db/oct high pass)
No high pass = dead tapped horn driver.
BTW, xti's are wonderful for things like this... eq, crossover, high pass, limiter, PASSWORD PROTECTION.....
Ok here's an update. I set up the PA at Gibralter trade center today and ran the auto Eq with a pink noise. put a little curve to my liking. then played some nickleback from an Ipod through it and pumped it all the way up. and yes I have the HP and limiter set to what you told me I should use. all I can say is HOLY CHIT MON. the pavilion is completly open at the one end and I walked 160 feet to the end of it. and then walked out of it another 20 feet. I could still feel the kick at 180 feet back with only 4 cabs loaded with only 1 fifteen in each and at a 1/4 of the wattage I used with 4 eighteens.
4 weeks ago I used 4 30 inch wide T48's at the same location. center loaded and v-plated. The T48's performed well too but I think JBells cabs have a more focused punch to them. if that makes any sense. I know what I wanted out of my low end and the T48's didn't quit have it but JBells cabs seem to be more of what I was looking for from a sub. Now we'll see how well they work with a live band and a kick drum running through it.
I will know tomorrow after sound check with my band.
4 weeks ago I used 4 30 inch wide T48's at the same location. center loaded and v-plated. The T48's performed well too but I think JBells cabs have a more focused punch to them. if that makes any sense. I know what I wanted out of my low end and the T48's didn't quit have it but JBells cabs seem to be more of what I was looking for from a sub. Now we'll see how well they work with a live band and a kick drum running through it.
I will know tomorrow after sound check with my band.
I believe what you are describing is the difference between flat to 40hz TH, vs the typical rising response FLH sound. Well, that, and the directionality of the TH is responsible for the bass at distance. (do us a favor, walk behind the subs while they are playing, and report back on the bass BEHIND.... I would bet some still don't believe they are directional.)
Looking forward to a full report.
JBells TH cabs
update: I did a live band sound check today with my new JBell TH subs. I am very happy
. The kick drum is loud and clear all the way to the back of the room and then some. and yes these subs are very directional. as you walk around the cab it gets softer. and on stage behind the cabs is nice and quiet. this makes for a very controlled sound. I love it. I even tried turning the cab to see if it makes a difference and it does. I had them aimed at the plywood side wall and they were rattling the crap out of the wall. when I turned them back to the center the walls stopped rattling. if that isn't directional, I'll kiss your ***. I have the perfect sub for me now. I will be building 4 more of these in a few weeks. then on to the perfect tops. any suggestions JBell, my new best friend? LOL
Thank you so much for this great sub that you and your friends designed.
Regards,
SHAWN
update: I did a live band sound check today with my new JBell TH subs. I am very happy
. The kick drum is loud and clear all the way to the back of the room and then some. and yes these subs are very directional. as you walk around the cab it gets softer. and on stage behind the cabs is nice and quiet. this makes for a very controlled sound. I love it. I even tried turning the cab to see if it makes a difference and it does. I had them aimed at the plywood side wall and they were rattling the crap out of the wall. when I turned them back to the center the walls stopped rattling. if that isn't directional, I'll kiss your ***. I have the perfect sub for me now. I will be building 4 more of these in a few weeks. then on to the perfect tops. any suggestions JBell, my new best friend? LOLThank you so much for this great sub that you and your friends designed.
Regards,
SHAWN
Attachments
update: I did a live band sound check today with my new JBell TH subs. I am very happy
Thank you so much for this great sub that you and your friends designed.
Regards,
SHAWN
Thanks for the review, and most importantly the confirmation on the directionality. There are thousands of designs that can make bass, but very few that are directional. If you are going to 'labor' to design tops that are directional, why would you not want your subs to be as well? The unachievable holy grail of sound reproduction would be 40-15000 all at the same polar response.
As for suggestions:
First, your woodworking looks good, make it look great. Take a router with a 45 degree bit at hit all of your edges, it'll keep the plywood from splintering at some point in the future. Next buy one of these: Search results for: 'texture' and add some texture. You'll be amazed what a little texture will do for the look.
As for tops, if you have read any of my threads, you'll see I've done a ton with 'OT style' cabinets. There are a few things that I'll mention.
1. the 10" long horn gives you a bunch of 500hz boxy sound, eq that out, or change the path length.
2. The side ports are feedback creators, put them in the horn plates, to the sides/front, not deep like omni/jack.
3. compression horn bi-amp'd. selenium 220 and goldwood 500 seem to be a reasonable and cheap combo.
4. overall dimension, if you build 16 1/8" x 23 1/8" x 18 cabinet size, you can use stock 15x22 metal grills.
5. I'm lazy, cutting horn sides with 45degree angles to meet the baffle and cabinet sides makes things go easier.
6. Go with more tops, cheaper drivers, vs fewer tops with more expensive drivers. I've kinda gotten to like the beta 12a-2.
7. hornresp... The above does not necessarily give you an exact 'plan' but rather gives you some guidelines on how to design and build your 'own'
8. xti amps. You can get xti1000 refurbs with full crown warranty for $350 and have all the dsp you could ever want to bi-amp your tops. A good match for up to 4 a side.
Several builders have used/recommend Acrytech's Duratex speaker coating.
While it can be applied via roller, using a hopper spray gun is recommended.
It's not as good as the "Truck Bed coating" but it costs about 1/10 as much.
Speaker Cabinet Coating for superior performance Speaker Cabinet Texture Coating in gloss or satin
While it can be applied via roller, using a hopper spray gun is recommended.
It's not as good as the "Truck Bed coating" but it costs about 1/10 as much.
Speaker Cabinet Coating for superior performance Speaker Cabinet Texture Coating in gloss or satin
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Thanks for the tips. as far as looks I'm not that worried about. The performance is my main concern. I move this stuff every weekend. My band plays Friday and Saturday every week. The crew I have to move gear can be a little rough LOL. The equipment gets beat up alot. I just throw more paint on them and they are as good as new. but I will be using a router on the edges. I just bought one a few weeks ago.
i did notice a lot of vibration on the horn mouth. I think I will try adding a cross brace at the end of the mouth. I used glue and screws so I know they can take some abuse.
I'm using a DCX2496 I can just run 3 way with the OT type cabs and subs. I have 3 QSC PLX3602's should be enough to do whatever I need. Thanks again.
and thank you Syd for helping me and for directing me to this forum.
regards,
SHAWN
i did notice a lot of vibration on the horn mouth. I think I will try adding a cross brace at the end of the mouth. I used glue and screws so I know they can take some abuse.
I'm using a DCX2496 I can just run 3 way with the OT type cabs and subs. I have 3 QSC PLX3602's should be enough to do whatever I need. Thanks again.
and thank you Syd for helping me and for directing me to this forum.
regards,
SHAWN
The show went great this weekend. The subs performed perfect. and they can take abuse too LOL. had lots of girls dancing on them
.
Here is a few more pics of my set up.
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Here is a few more pics of my set up.
Attachments
very cool, thanks for sharing.
Love your setup of your subs.
Here's a tip for you that may come in handy some day. If you are running 2 sub amp channels, you can use your dcx and delay the outside pair up to about a couple milliseconds if you need to spread your bass wide. (around 2ms got my 45 degree off axis, the same spl as head on.) If you play a 'wider than deep' area, it may come in handy.
BTW -- couldn't see your tops, what do you run today?
Love your setup of your subs.
Here's a tip for you that may come in handy some day. If you are running 2 sub amp channels, you can use your dcx and delay the outside pair up to about a couple milliseconds if you need to spread your bass wide. (around 2ms got my 45 degree off axis, the same spl as head on.) If you play a 'wider than deep' area, it may come in handy.
BTW -- couldn't see your tops, what do you run today?
I'm using 4 QSC HPR152i for tops. powered 15 and a horn. we hang Room 13 banners in front of them. that why you can't see them.
thanks for the tip. I will do that at a couple of the wide club that we do.
do you think I need to delay the tops at all because of the length of the TH horn.
I used to delay for the T48s because they had 9 feet of horn and I could hear it tighten up the sound with the delay on the tops.
The TH's don't seem to have a problem with that. maybe because the driver is in the mouth and shorter horn path.
Thank you,
SHAWN
thanks for the tip. I will do that at a couple of the wide club that we do.
do you think I need to delay the tops at all because of the length of the TH horn.
I used to delay for the T48s because they had 9 feet of horn and I could hear it tighten up the sound with the delay on the tops.
The TH's don't seem to have a problem with that. maybe because the driver is in the mouth and shorter horn path.
Thank you,
SHAWN
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