[Allanf714]

I must premise this statement with the fact that I am not well versed on the subject... but wouldn't a ground filed measurement outside provide us with the best FR comparison to other subs? In this situation I'm not sure how far you would place the mic from the opening? maybe 1 meter (like sensitivity tests).

Hopefully you've got some help to move this thing around

 

[myn]

I must premise this statement with the fact that I am not well versed on the subject... but wouldn't a ground filed measurement outside provide us with the best FR comparison to other subs? In this situation I'm not sure how far you would place the mic from the opening? maybe 1 meter (like sensitivity tests).

Hopefully you've got some help to move this thing around

Good point. An outside measurement at 10 meters like Danley tests would be ideal. I keep forgeting he is in FL with probably nice weather unlike where I am :/.

 

[aceinc]

Yes the weather is nice, but the person that is supposed to get the sub when I'm done never showed up to help.

I have done some testing, but not enough. Below are some plots in my living room. All plots have no equalization. The first plot is of my main sub(s) documented here - http://www.hometheatershack.com/forums/diy-subwoofers/2569-waf-limited-sub-system.html the only differences from this link and as tested is the subs are slightly off center and pushed together.

The second is as I described above with the RS-meter as a mic and about 2" away from the mouth. Third graph is with the sub centered and the mouth pointing straight up. Both the last and the first graph were taken from the main listening position about 8-10' away. The mic in these (first & last) two tests was a Behringer ECM 8000.

Paul

 

[myn]

Hows it sound? Better or worst than your existing subs?

Hows the SPL? Are you able to drive the drivers to audible distortion with your existing amp?

 

[aceinc]

Unequalized it doesn't have the same low freq visceral sensation that my DS15-titanic combo does. I put my BFD back in, and dialed in a flat house curve, and it sounds better.

I still have the mouth facing up about two feet in front of a bay window. I will be doing some listening today to see whether I can get it to distort. One thing I would like to try is to see if I can get the Pioneer AV processor to send sub data to the sub when the source is stereo, either MP3 player, CD, or ipod. I would like to try some sub torture test mixes.

Paul

 

[myn]

Couple of thoughts.

Do you think the 60 degree angle perhaps plays a bigger role in the enclosure than just allowing the bulky W8-740P drivers to fit? What we do know is the original drivers RMK had were significantly smaller than the W8-740P drivers Danley sent to him later. I am inclined to think that 60 degree angle was more than just a design augmentation to allow the drivers to fit as the first one could have fit without the 60 degree angle.

Old driver on left, new driver on right:

I know there was much discussion in the collaborative tapped horn forum around the Trio 8 driver. Some said it may work, some said it may not. The only real way was to try it. Do you think the W8-740P driver would be a good thing to try? Perhaps gaining better performance?

retrospect is always 20:20. I'm just very curious to know if you had used the W8-740P drivers with the 60 degree angle, mimicing the Danley design verbatim if the performance would have been better?

Based on your comments so far I would have expected a SPUD to outperform your existing array of subs as from all of the reviews I've seen "They are 2x a DTS-20" and "outdue quad fathoms".

Perhaps the placement is a larger factor? Have you tried corner loading that beast?

I wish I lived closer. I'd love to come and help.

 

[aceinc]

Well I watched the movie "Wanted" today, while I would not recommend it from an aesthetic, or artistic point of it does have lots of "boom factor." I had the TH-SPUD upfiring with the BFD in place.

I used the Pioneer MCACC to calibrate the room, and it set the sub at -8db. I boosted the signal to -2db, because I wanted to feel the movie, and I was testing the sub after all.

Let me digress, I did a bit of research on my NAD 2200PE and I found this quote;

"The NAD 2200 is so powerful in the normal stereo mode that few listeners will ever need more. For special situations the two channels of the 2200 can be bridged to form a mono amp of truly immense power. Its rated continuous sine-wave output is 400 watts, while its dynamic power output exceeds 1200 watts into 8 ohms and 1600 watts into 4 ohms"

So I guess for the moment I do not need to look for another amp.

Meanwhile back to my impressions, with the system thus configured and the sub about 8' behind the listening position, I watched to the movie. The bass seemed as good as the DS15-combo, I could feel the things I believe I should feel. Everything felt tight and fast. At the end of the movie there is a "theme song" with fairly heavy bass, so I cranked the volume up from -15 DB to -7 DB before I heard distortion, remembering I had the bass over by about 6 DB according to the way MCACC wanted it setup, I think it did really well.

This is rather subjective, and I will get back to the objective soon.

Paul

 

[Allanf714]

First let me say Paul, thank you for all of your efforts. I"ve enjoyed watching this thread with much anticipation.

I had kindof hoped for more impressive measurements as well. I'm really wondering if that 60 degree angle had more to do with maintaining a particular width towards the mouth of the horn.

I suspect we will never know until someone builds one to spec (with quilted dampening). If that happens.... then we'll have the oportunity to try both drivers and see which produces better results.

Anyone in the Austin area interested in a collaborative project?

 

[myn]

Anyone in the Austin area interested in a collaborative project?

Wish I lived closer

I'd love to see some success in this.

 

[myn]

Looks like their has been some progress made over at DIYAudio by someone recreating the TH-SPUD with damping and the W8 driver: http://www.diyaudio.com/forums/showthread.php?postid=1788175#post1788175

 

[aceinc]

Well my wife has been tolerant and I have left the TH in the room pointing straight up. I still have the horn tamed with a BFD. from a subjective point of view I have been quite pleased with its performance.

I would recommend the build to anyone that has the space for the cabinet. I have no way to compare whether the mods I made have a positive or negative effect on the outcome. But using the drivers I used make the build easier which is a consideration for weekend warriors like me.

I currently have the sub set for what my pioneer AV receiver's MCCAC calls for and will be leaving it in place until either I find a home for it, or my wife gets tired of the box in the living room. If I can't find a home for it I will remove the drivers and use them in another project.

Paul

 

[brandonnash]

Is your friend not getting the sub from you?
Posted via Mobile Device

 

[aceinc]

It is actually one of my employees. He has blown me off on two occassions.

I think he is embarassed to mention it again.

I was thinking that I have other drivers for a decent sounding speaker that will do pretty good into the 60hz range. I might consider adding a pair of these 8 inchers ported with a 500 watt plate amp to each side if I decide to build them. I need to see how big a cabinet I would need. Should get me to 30 hz or better.

This is if I can get the time, and ambition.

Paul

 

[brandonnash]

Well I may be in southern Florida this summer. If I am and haven't found another subwoofer by then I will shoot you a PM to see if you want to part with the spud.
Posted via Mobile Device

 

[bpratt]

I thought I'd post one more picture of the unit with the top off. It looks a bit better in the fresh air.

The bad news is I don't have a garage or a basement, the good news is that this is S florida and this is the best time of year to be outdoors.

Just wondering what sized plywood that you are using in this project ?

I hope I haven't overlooked a post where you might have already mentioned them.

Thanks.

 

[patchesj]

And it looks like all of the TH-SPUD photos have been taken off line.

 

[Ricci]

Those were proprietary internal DSL documents and should not have been posted to the web. Also it was just plain bad taste to do that to a guy who has done so much for the DIY community over the years. IMHO. I'm not saying that I didn't enjoy seeing the documents. That would be a lie, but I would've never posted them to the web for all to see myself. (Aceinc, I know it wasn't you who brought those to light so I'm not directing this rant at you.)

 

[patchesj]

Those were proprietary internal DSL documents and should not have been posted to the web. Also it was just plain bad taste to do that to a guy who has done so much for the DIY community over the years. IMHO. I'm not saying that I didn't enjoy seeing the documents. That would be a lie, but I would've never posted them to the web for all to see myself. (Aceinc, I know it wasn't you who brought those to light so I'm not directing this rant at you.)

Agreed! TH design info (detailed design info) seems to be much more difficult to find than the more main stream types.

Edit: DIY design info....

 

[paulspencer]

I'd be curious to hear about a music comparison! I think that would be the real test from a SQ point of view.