Josh Ricci said:
Hi Josh. I tried a few combinations with HornResp yesterday, and mine look somewhat similar to what others have posted. I kept the compression ratio at 3:1 or less to hopefully make it safer. Not super smooth, but within a few dB for not having to crank down the areas any more.
1W response:
Params:
Here's that "tremendous response" we were discussing. Assuming nothing falls apart (the cone, the box, your house) of course.
Standard half space:
In a corner (eighth space)- a theoretical 135+ dB from 15 Hz up:
You should build it so we can follow and see if it actually does that, heh. Maybe check with TC Sounds first and see if they know how strong the cone is and what kind of compression ratio they think it could take at full excursion.
Yep, that's hindsight for ya. In looking through your GTG REW graphs, I assumed the peaks that were common to all the subs were probably room induced (such as the 70 Hz peak). The 80+ Hz peaks and dips to the TH50 were unique and also quite similar to some of the HornResp predictions for slightly larger MTX horns (20 Hz TH). Example:
Regards,
Keith
LMS 5400 18 Parameters
When entering the parameters for the LMS 5400 18 into Hornresp it calculated values are similar to, but slightly different from the values in Post #3311.
For Josh_Ricci: Are your LMS 5400 18 parameters measured?
For HornsKeith: Your parameters differ a bit from the ones Josh Ricci posted in Post #3311/#3316. Are these parameters measured?
Regards,
When entering the parameters for the LMS 5400 18 into Hornresp it calculated values are similar to, but slightly different from the values in Post #3311.
For Josh_Ricci: Are your LMS 5400 18 parameters measured?
For HornsKeith: Your parameters differ a bit from the ones Josh Ricci posted in Post #3311/#3316. Are these parameters measured?
Regards,
Re: LMS 5400 18 Parameters
Thanks. Yep the GTG measurements all have a big 70hz and 45hz peak from the room plus a few other issues. The TH's seemed to exaggerate this a bit more and had some peaks higher in the pass band. I will try to give some TH design a try this summer. Possibly with the LMS 18 or the SDX.The models that have been posted look decent. I won't have time to play with them until later, but the output potential looks nice. I noticed that the graph posted for the MTX9500 looks really good especially the sensitivity. Is that for 1/2 space?
They are Praxis measurements, not of my particular driver, but TC is usually very close. I also have a WT3. The BL, MMS, RE, SD, LE is all spot on. The xmax and xmech are real figures.
HornsKeith said:
Hi Josh. I tried a few combinations with HornResp yesterday, and mine look somewhat similar to what others have posted. I kept the compression ratio at 3:1 or less to hopefully make it safer. Not super smooth, but within a few dB for not having to crank down the areas any more.
1W response:
Params:
Here's that "tremendous response" we were discussing. Assuming nothing falls apart (the cone, the box, your house) of course.
Standard half space:
In a corner (eighth space)- a theoretical 135+ dB from 15 Hz up:
You should build it so we can follow and see if it actually does that, heh. Maybe check with TC Sounds first and see if they know how strong the cone is and what kind of compression ratio they think it could take at full excursion.
Yep, that's hindsight for ya. In looking through your GTG REW graphs, I assumed the peaks that were common to all the subs were probably room induced (such as the 70 Hz peak). The 80+ Hz peaks and dips to the TH50 were unique and also quite similar to some of the HornResp predictions for slightly larger MTX horns (20 Hz TH). Example:
Regards,
Keith
Thanks. Yep the GTG measurements all have a big 70hz and 45hz peak from the room plus a few other issues. The TH's seemed to exaggerate this a bit more and had some peaks higher in the pass band. I will try to give some TH design a try this summer. Possibly with the LMS 18 or the SDX.The models that have been posted look decent. I won't have time to play with them until later, but the output potential looks nice. I noticed that the graph posted for the MTX9500 looks really good especially the sensitivity. Is that for 1/2 space?
tb46 said:
They are Praxis measurements, not of my particular driver, but TC is usually very close. I also have a WT3. The BL, MMS, RE, SD, LE is all spot on. The xmax and xmech are real figures.
Re: Re: LMS 5400 18 Parameters
Yes, half space / 2.83V. The TH params are just a variant of what Bill Cowan posted in #699. The only unknown for me was the driver Le, which I couldn't find listed anywhere. I just dummied in 3 mH for modeling. Hopefully it's not too much higher than that, which would make the response much less smooth.
Regards,
Keith
Josh Ricci said:
Yes, half space / 2.83V. The TH params are just a variant of what Bill Cowan posted in #699. The only unknown for me was the driver Le, which I couldn't find listed anywhere. I just dummied in 3 mH for modeling. Hopefully it's not too much higher than that, which would make the response much less smooth.
Regards,
Keith
LMS 18 TH
How do these look? One is 600L and the other is 900L. I think the 600L looks decent if it's do able, but I'm a bit concerned with the first major spike that always seems to be present in the pass band. How bad is that in actuality? I can go to a 60-80hz steep xover but I don't think that will be enough. I guess I could notch filter it out.
How do these look? One is 600L and the other is 900L. I think the 600L looks decent if it's do able, but I'm a bit concerned with the first major spike that always seems to be present in the pass band. How bad is that in actuality? I can go to a 60-80hz steep xover but I don't think that will be enough. I guess I could notch filter it out.
As far as I know, the longest tapped horn built to date is Chris's Lab12.
Chris built 2, I built 1, and Tone P just needs to put on
the last panel to complete his. The acoustic length is just short of 19 feet.
Josh: are you seriously thinking about building this 24 foot
monster? If driven hard, it could cause structural failure of your house.
If you take your horn outside to test (2Pi), that peak at 68 Hz will not exist.
Put a little polyester in the throat, and peaks will not be a problem.
OTOH, room effects are going to cause major problems
Chris built 2, I built 1, and Tone P just needs to put on
the last panel to complete his. The acoustic length is just short of 19 feet.
Josh: are you seriously thinking about building this 24 foot
monster? If driven hard, it could cause structural failure of your house.
If you take your horn outside to test (2Pi), that peak at 68 Hz will not exist.
Put a little polyester in the throat, and peaks will not be a problem.
OTOH, room effects are going to cause major problems
Well...I'm fairly serious.
I've already got subwoofers that make me worry about structural damage sometimes, below 25hz. One in particular. That's why I wanted to use one of the 3 drivers I listed originally I already have them and I'm very familiar with what they'll do in standard vented or sealed enclosures. It'll be easier for me to tell what the enclosure is doing to the drivers output. I just had a PM from someone yesterday that may turn into an interesting TH development. We'll see. I heard a TH50 pushed quite hard in a 4000cu ft room in someone's home 2 weeks ago, so yes, I know how dumb this would be in a residential setting.
the TH50 was pretty wild. Who said it was destined to be in a home? It'd be for fun and research mostly.
I've already got subwoofers that make me worry about structural damage sometimes, below 25hz. One in particular. That's why I wanted to use one of the 3 drivers I listed originally I already have them and I'm very familiar with what they'll do in standard vented or sealed enclosures. It'll be easier for me to tell what the enclosure is doing to the drivers output. I just had a PM from someone yesterday that may turn into an interesting TH development. We'll see. I heard a TH50 pushed quite hard in a 4000cu ft room in someone's home 2 weeks ago, so yes, I know how dumb this would be in a residential setting.
the TH50 was pretty wild. Who said it was destined to be in a home? It'd be for fun and research mostly.
My longest tapped horn to date was the double Tang Band W8-740. It is still banned from the house. This thing would rattle EVERYTHING in the house. Path lenght was a little over 19 feet.
http://www.diyaudio.com/forums/showthread.php?postid=1627597#post1627597
Rgs, JLH
http://www.diyaudio.com/forums/showthread.php?postid=1627597#post1627597
Rgs, JLH
Impulse response comparison
Hi JLH,
I have always liked the design you shared in Post #2362, it gives such great control over the size of the compression chamber and the horn throat. As David McBean added an impulse response plot to Hornresp, here is yours and the SPUD:
Regards,
Hi JLH,
I have always liked the design you shared in Post #2362, it gives such great control over the size of the compression chamber and the horn throat. As David McBean added an impulse response plot to Hornresp, here is yours and the SPUD:
Regards,
Attachments
impulse response
Hi JLH,
quote: "... but is that a good impulse response? What does one look for in a "good" impulse response?"
For a tapped horn it looks quite good to me, actually looks better than the simulated response for the SPUD, but then there is the question, how do they compare in a measurement, and more importantly what do they sound like?
There is always something else to investigate, there may actually be a reason why I have always ended up with dual 15" in sealed boxes.
Regards,
Hi JLH,
quote: "... but is that a good impulse response? What does one look for in a "good" impulse response?"
For a tapped horn it looks quite good to me, actually looks better than the simulated response for the SPUD, but then there is the question, how do they compare in a measurement, and more importantly what do they sound like?
There is always something else to investigate, there may actually be a reason why I have always ended up with dual 15" in sealed boxes.
Regards,
impulse response
Hi JLH,
Just as a comparison: Bas Horneman has a very nice thread on a horn project, and I tried to model his bass module in Hornresp, anyhow, here is the impulse response:
diyAudio Forums > Top >Loudspeakers >Full Range >Pictorial of an exponential/radial horn being made for me by a friend...:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=76396&perpage=25&highlight=&pagenumber=1
Hi JLH,
Just as a comparison: Bas Horneman has a very nice thread on a horn project, and I tried to model his bass module in Hornresp, anyhow, here is the impulse response:
diyAudio Forums > Top >Loudspeakers >Full Range >Pictorial of an exponential/radial horn being made for me by a friend...:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=76396&perpage=25&highlight=&pagenumber=1
