18" long? hmm. exactly the length of my top horn in the pic above... sounds like I must have been on to something.... Also, my big TH was 270, and you're at 269... hmm... hmm... maybe my big TH with your non parallel center dividers, might be something I should investigate...
I used 1800hz 1065's, not 3500hz 1063 piezo's. I had dismal luck with the harshness of the 1063's as well. However, I completely understand your lack of success with the piezo's.
I'm interested in your phase plug, that's one thing I don't know how to model, or accomplish. I'm assuming you are doing a 'stare and compare' approach to the phase plug?
I know before I had success with my big TH, I was tempted to take eminence standard dual 15 box, and mod it, to gain a little directivity, like this. I remember at the time, not being able to determine how to best model ports in the horn throat vs. front of cabinet.
I used 1800hz 1065's, not 3500hz 1063 piezo's. I had dismal luck with the harshness of the 1063's as well. However, I completely understand your lack of success with the piezo's.
I'm interested in your phase plug, that's one thing I don't know how to model, or accomplish. I'm assuming you are doing a 'stare and compare' approach to the phase plug?
I know before I had success with my big TH, I was tempted to take eminence standard dual 15 box, and mod it, to gain a little directivity, like this. I remember at the time, not being able to determine how to best model ports in the horn throat vs. front of cabinet.
Attachments
Jim & Scott:
I have a standing request: If in all your experimentation, you find designs that are a good fit for JBL 2226 or 2206 keep me in mind:
Selling the JBL I have to buy Eminence drivers does NOT fit my needs/plans/requirements.
Happy New Year & Much DIY success in 2009.
Syd
* BTW: Jim, You have become "anonymous" on another forum
I have a standing request: If in all your experimentation, you find designs that are a good fit for JBL 2226 or 2206 keep me in mind:
Selling the JBL I have to buy Eminence drivers does NOT fit my needs/plans/requirements.
Happy New Year & Much DIY success in 2009.
Syd
* BTW: Jim, You have become "anonymous" on another forum
YOU ARE NOT GOING TO LIKE THIS
After more than 30 cabinets and months of every possible minute,
countless sleepless nights, 6 lbs lost, and a decimated pile of wood, I have reached the following conclusion:
A DIY low spl 20-80 or 40-100hz Tapped horn sub for home use is
fairly easy to come up with help from hornresp. They sound good too.
A DIY TH under 40x30x24, with an average output from 42hz to 120hz at 103 db +-2 db that is equal to two direct radiators, that is portable enough to fit 4 in a van with everything else for high spl pro sound use.....is not possible. Unless you are Tom Danley.
The closest I came was 102.5db average but poor response below 50hz equal to the direct radiator. That cabinet had a ton of angles and tapering parts pieced together by hand such that it would be next to impossible to turn out 6 properly built cabinets with decent hand tools. To make matters worse there was a lot of instinctual work in it making it impossible to re-model the built box in horn resp. The top end was really nice and it certainly sent my only titan to the scrap heap (along with every shred of BFM paperwork).
Sorry Folks.
Anyone got a really good double 15 box plan???
Maybe one of those angled jobs with the drivers facing each other.
After more than 30 cabinets and months of every possible minute,
countless sleepless nights, 6 lbs lost, and a decimated pile of wood, I have reached the following conclusion:
A DIY low spl 20-80 or 40-100hz Tapped horn sub for home use is
fairly easy to come up with help from hornresp. They sound good too.
A DIY TH under 40x30x24, with an average output from 42hz to 120hz at 103 db +-2 db that is equal to two direct radiators, that is portable enough to fit 4 in a van with everything else for high spl pro sound use.....is not possible. Unless you are Tom Danley.
The closest I came was 102.5db average but poor response below 50hz equal to the direct radiator. That cabinet had a ton of angles and tapering parts pieced together by hand such that it would be next to impossible to turn out 6 properly built cabinets with decent hand tools. To make matters worse there was a lot of instinctual work in it making it impossible to re-model the built box in horn resp. The top end was really nice and it certainly sent my only titan to the scrap heap (along with every shred of BFM paperwork).
Sorry Folks.
Anyone got a really good double 15 box plan???
Maybe one of those angled jobs with the drivers facing each other.
HK26147
Go to the jbl website and look for thier double 15 theatre install bin. Use the measurements there. The only thing you won't have is the port depth. There are two 4" round ports.
Or you can use the various scoop plans available on the web.
They were used in the scoop. If you are in FLA I have an original set of JBL double 15 scoop bins you can have.
Go to the jbl website and look for thier double 15 theatre install bin. Use the measurements there. The only thing you won't have is the port depth. There are two 4" round ports.
Or you can use the various scoop plans available on the web.
They were used in the scoop. If you are in FLA I have an original set of JBL double 15 scoop bins you can have.
Jbell
My new box design has no ports.
Phase plug.... I have an old cone from a blown kappa. I'll make a mold from that and use a touchy feely approach do dial it in.
I already excluded the phase plug area from the throat when I did the cabinet in horn resp. It won't be too fancy.
It's primary purpose is to get around the compression driver in a nicer way and extend the upper end to above the crossover point.
I have a feeling there may be no point in building them without decent subs.
Tapers will smooth out your big TH.... LOL!
Lord that sounded funny
My new box design has no ports.
Phase plug.... I have an old cone from a blown kappa. I'll make a mold from that and use a touchy feely approach do dial it in.
I already excluded the phase plug area from the throat when I did the cabinet in horn resp. It won't be too fancy.
It's primary purpose is to get around the compression driver in a nicer way and extend the upper end to above the crossover point.
I have a feeling there may be no point in building them without decent subs.
Tapers will smooth out your big TH.... LOL!
Lord that sounded funny
screamers... if you are giving up on TH.. maybe there is something in this list of cabinets that can work for you...
http://photofile.name/users/tda-audio/182333/3252838/
syd:
being anonymous isn't all bad..... thanks.
http://photofile.name/users/tda-audio/182333/3252838/
syd:
being anonymous isn't all bad..... thanks.
Besides the Mini clones
I built, I haven't come across a TH design that I want to build. The 2 minis go 50-200 Hz 127-130 db. They are paired with either a 12" or 15" inch 2 way. They sound like a HT sub.
I just posted to see if anyone can come up with
a TH design that is single cab. 135 plus db. 40/42 Hz -150/200. 2Pi
Should be interesting if anyone takes up the challenge.
I built, I haven't come across a TH design that I want to build. The 2 minis go 50-200 Hz 127-130 db. They are paired with either a 12" or 15" inch 2 way. They sound like a HT sub.
I just posted to see if anyone can come up with
a TH design that is single cab. 135 plus db. 40/42 Hz -150/200. 2Pi
Should be interesting if anyone takes up the challenge.
"Go to the jbl website and look for thier double 15 theatre install bin. Use the measurements there. The only thing you won't have is the port depth. There are two 4" round ports. "
Sorry, I took a tape-measure to mine. Two 5-5/16" ports, 4-1/2" long, 8 cu ft net.
"Or you can use the various scoop plans available on the web.
They were used in the scoop. If you are in FLA I have an original set of JBL double 15 scoop bins you can have."
The scoops were discontinued around 1981, long before the 2226 was offered. Real JBL scoops are not to be recommended for touring, they are particle board, too heavy, and crumble when subjected to impact. Plywood copies by Sonic (and others) are a better choice.
Sorry, I took a tape-measure to mine. Two 5-5/16" ports, 4-1/2" long, 8 cu ft net.
"Or you can use the various scoop plans available on the web.
They were used in the scoop. If you are in FLA I have an original set of JBL double 15 scoop bins you can have."
The scoops were discontinued around 1981, long before the 2226 was offered. Real JBL scoops are not to be recommended for touring, they are particle board, too heavy, and crumble when subjected to impact. Plywood copies by Sonic (and others) are a better choice.
FlipC said:
If the PASUB drivers ever make it to the market then a PA450 in a TH-115-style tapped horn might even beat the "real" TH-115 for maximum output, both Xmax and thermal handling are supposedly a lot higher than the B&C driver the TH-115 uses.
Or the relatively light cone might collapse under the strain, though Erik at PASUB assures me this is unlikely -- still, the proof of the pudding is in the eating, until someone tries one this is all speculation.
Also getting a 40Hz TH to go up to 200Hz needs some special tricks which Tom seems to have (according to the TH-115 data sheet) but nobody else does...
Ian
Ian
Hadn't seen the PASub so I will check those out.
But unfortunately No, I am not happy. That isn't the point of the exercise. Which is to see if the members of the forum can jointly come up with a DIY TH sub that can do the specs I posted. I can come up with a horn that does them. I already have. 300 Lt at that.(though at 4 cabs for the 40Hz part)
There is a huge difference between
HT and PA subs. It is simple to come up with a ridiculously good TH for HT because max SPL isn't the issue. Where as in a PA both freq and SPL are a major concern.
Hadn't seen the PASub so I will check those out.
But unfortunately No, I am not happy. That isn't the point of the exercise. Which is to see if the members of the forum can jointly come up with a DIY TH sub that can do the specs I posted. I can come up with a horn that does them. I already have. 300 Lt at that.(though at 4 cabs for the 40Hz part)
There is a huge difference between
HT and PA subs. It is simple to come up with a ridiculously good TH for HT because max SPL isn't the issue. Where as in a PA both freq and SPL are a major concern.
djk said:
The PASUB 15" is probably better for a TH than the 18".
The Eminence may be slightly more efficient -- though I'm surprised given the much lower BL -- but has nowhere near the maximum SPL -- which *is* the challenge that was set, after all -- because Xmax is so much smaller (9mm vs 20mm).
A tapped horn is no different to any other enclosure in that most drivers run out of Xmax before they run out of thermal power handling.
djk said:
You asked for maximum SPL and efficiency in a given size box, not practicality or low cost. If you're worried about port sizes use 8 18" PRs instead, these are available with more than 2" p-p travel.
Nobody's saying the result will be cheap -- and cramming in 4 18" drivers and 8 18" PRs into a 500l box will be challenging to say the least -- but I doubt if any same-sized TH can match the 144dB maximum SPL of the result, albeit needing a ginormous amplifier (Powersoft K20?) to do so.
Thanks for the correction on those JBL's.
For some reason I thought they were 4".
On the scoops... I have a pair of REAL Jbl scoops pulled out of service last year. They had 2225H in them although there are lots of Reggae guys running around with 2226 in them.
The cabinets are the grey JBL boxes and they are most certainly plywood. There are two internal panels that may be flakeboard.
Dumb question. About how much theoretical gain difference vs frequency
would two 40hz tapped horns have over one? For example at 100hz 60 hz and 40hz compared with a double 15? Assuming a single tapped and a single 15 are putting out about the same level at 1w.
For some reason I thought they were 4".
On the scoops... I have a pair of REAL Jbl scoops pulled out of service last year. They had 2225H in them although there are lots of Reggae guys running around with 2226 in them.
The cabinets are the grey JBL boxes and they are most certainly plywood. There are two internal panels that may be flakeboard.
Dumb question. About how much theoretical gain difference vs frequency
would two 40hz tapped horns have over one? For example at 100hz 60 hz and 40hz compared with a double 15? Assuming a single tapped and a single 15 are putting out about the same level at 1w.
As i have said. You have to put another fold in the first section of the horn and loose that unused space. In your design the area behind the driver is acting as a chamber and your horn starts almost a feet later. There is a reason why Tom placed the driver with the magnet facing to the out side.
Look at the picture here to understand better what i am saying.
http://img264.imageshack.us/img264/8913/h15mkiieditedfl3.jpg
I dont post here offten and i really hate this moderation thing. Grrrrrrrrrrrr
Look at the picture here to understand better what i am saying.
http://img264.imageshack.us/img264/8913/h15mkiieditedfl3.jpg
I dont post here offten and i really hate this moderation thing. Grrrrrrrrrrrr
Thanks MarJan
I sort of gathered that. I eliminated the wasted space and added another fold and wound up with a below 80 only sub
and the associated gain loss. These would sound awesome with my old Apogee SX3's but I can't lift em!
I did recalculate everything in Hornresp first. Above 80 it was useless i.e. absoultely zero gain over a direct radiator.
That's where the battle is. Getting gain above 80hz without losing bass. I managed to get pretty close once.
I also realized you need at least a pair per side.
I sort of gathered that. I eliminated the wasted space and added another fold and wound up with a below 80 only sub
and the associated gain loss. These would sound awesome with my old Apogee SX3's but I can't lift em!
I did recalculate everything in Hornresp first. Above 80 it was useless i.e. absoultely zero gain over a direct radiator.
That's where the battle is. Getting gain above 80hz without losing bass. I managed to get pretty close once.
I also realized you need at least a pair per side.