Ideas as to what is inside? Need 16Hz for digital pipe organ-help?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
http://www.ttechcorp.com/e3.htm

To design a world-class speaker, we broke from the conventional wisdom in the following aspects:

(a) we used very low-mass woofer cones and large magnets for superb damping, a design choice that normally conflicts with the goal of extreme low-frequency output amplitude,

(b) we employed active equalization to make up for the loss in low-frequencies resulting from low-mass cones (we ruled out passive equalization due to waste of mid-range power from the user's amplifier),

(c) we employed two such cones (i.e., two separate woofers) each having a 15 inch diameter, in each speaker cabinet, to handle the boosted signal power produced by the equalization,

(d) we planned the use of the PRESTANT - I system as a pair (which reduces 2nd harmonic distortion by 50% and 3rd harmonic distortion by 75%), although magnificent performance is possible using just one of our speakers, and

(e) we took a cue from the design of the prestant organ pipe, and constructed our low-frequency cabinet to have a mouth at the bottom (another subject of extensive computer analysis), and we consulted organ builders about how to prevent resonances, buzzes and rattles in the cabinet, and

(f) last but not least, we commissioned an award-winning furniture designer to build a cabinet as beautifully unique in its esthetics as it is in its acoustic properties.


Like a prestant organ pipe, our speaker's mouth is tuned. Magnificent walnut veneer is used for the exterior cabinet surface. The cabinet walls are all one inch thick and secured using proprietary techniques. The mouth of the system is part of an "S" shaped duct that divides the interior of the cabinet into three chambers. The bottom chamber, opening to the acoustic environment via the mouth, uses the floor as one of its walls. Thus, one can actually feel the pedal notes of the organ, or the bass drum in a symphonic work.

We discovered after our first design that any listener could hear the superiority of the result. Still, we weren't satisfied, because in the initial design, response was flat (without equalization) only down to 28 Hz. After a revision to the design, and the addition of active equalization, and still two more revisions to optimize the equalizer design, we were satisfied. Never before have we as music lovers been so pleased with the sound of electronically reproduced music. And we discovered that when it sounds right for pipe organ music, it sounds right for everything else. Most speaker designers would have stopped with a design employing a single small 12 inch woofer, falling far short of even our rejected first-pass attempt. Their designs strain unsuccessfully to reproduce the bass drum sounds in Stravinsky's "Rite of Spring" (compare theirs to ours while auditioning Leonard Bernstein's version with the Israel Philharmonic on Deutsche-Grammophon compact disc # 431 045-2).

Large-cone woofers are used in our system because, although frequency response at small signal levels (low loudness) can be addressed by smaller woofer diameters, at high loudness these smaller speakers can do little but flap and flutter their cones in a frantic frenzy. The use of large cones provides movement of sufficient air to sustain the loudness of pipe organ pedal sound in a home listening environment.
 
asiquis said:
To design a world-class speaker, we broke from the conventional wisdom in the following...

...use of large cones provides movement of sufficient air to sustain the loudness of pipe organ pedal sound in a home listening environment.

If you're going to post on a DIY site, should you not provide some more detail - otherwise, you should be posting in the Vendor's Bazaar Forum. How about:
1) Which EA drivers (and point to a link with the details)?
2) What active equalisation and what circuit you use for this?
3) What amplifier are you using to drive this (and maybe a circuit if it's your own design)?
4) What box alignment are you using (details)?
 
Re: Re: Ideas as to what is inside? Need 16Hz for digital pipe organ-help?

Cloth Ears said:


If you're going to post on a DIY site, should you not provide some more detail - otherwise, you should be posting in the Vendor's Bazaar Forum. How about:
1) Which EA drivers (and point to a link with the details)?
2) What active equalisation and what circuit you use for this?
3) What amplifier are you using to drive this (and maybe a circuit if it's your own design)?
4) What box alignment are you using (details)?

I don't think he's the maufacturer/designer/vendor. He's trying to find "Ideas as to what is inside" and wants us to help.

Anyway ......

Why do you want to emulate this design in particular?
Is it a subwoofer for a Hi-Fi setup?
What SPL do you need (volume)?
You want it to do 16Hz but how high will it need to go?
Do you want accurate? .... or just efficiently powerful?
What are your space constraints? (Bigger is generally better for low frequencies.)

Tell us more ..... and welcome to the forum,
Martin:)
 
Re: Re: Re: Ideas as to what is inside? Need 16Hz for digital pipe organ-help?

Sonusthree said:
I don't think he's the maufacturer/designer/vendor. He's trying to find "Ideas as to what is inside" and wants us to help.

Ulp! My apologies, asiquis. I jumped the gun a little.

My first attempt with this is to mail the appropriate party, in this case ttechcorp@earthlink.net is on their website. You'd be surprised (sometimes) how much info they will sometimes release to an individual.

I'm probably with Martin in that you needn't necessarily look at a particular manufacturer (excepting in the looks department - they do look nice) with regards performance. For what you may be wanting, size is generally all that is required - how much depends on your wants and your budget.

My suggestion, if you can stretch it, is that a sealed box (unlike the one you posted) would provide more accurate sound, but would probably be a bit more expensive to implement. But, that is my opinion...:)

Again, my apologies.
 
16 Hz subwoofer insides clarification!!

I was unclear with my post.
Thanks for those-Sonusthree/Martin- that figured out what I was trying to ask. I am not the designer of the Talbot tech Prestant-I subwoofer. I was intrigued with the size and the part I bolded the type face:
"The cabinet walls are all one inch thick and secured using proprietary techniques. The mouth of the system is part of an "S" shaped duct that divides the interior of the cabinet into three chambers. The bottom chamber, opening to the acoustic environment via the mouth, uses the floor as one of its walls."

I have been reading until I am bleary eyed on folded horns and TL designs and thought this must have some interesting "stuff" inside OR it could be hype. Is it a folded something?-- who knows, that is what I was looking for widom on.

I thought there was a lot coming from a such a small package...

The venue is a circa 1870 30'X 40' frame building with a 25' high peaked ceilingand th origianl wooden plank floors. The hope is to get down to 16 Hz with some autority and have it musical low distortion--tall order I know from my reaing thus far. We have 2 corners at the front where the sub(s) could reside.

I am a priest at a small parish north of Toronto Canada that appreciates the gifts of our young organist/musician and wish to support him. I also enjoy woodworking and have a limited budget hence the DIY endeavor.

The organ dealer nearby wishes to sell us 6000.00CAN worth of Definitive Technology speakers which he calims are the best in the world. Maybe you folk would have a comment on that stement!!!

Thanks for the 'venting" or would that be "porting" on this forum...I appreciate the hours of study and labours you folk have out in to turn out the great projects I read on these forms.
Thanks
Fr. Ray
 
The organ dealer nearby wishes to sell us 6000.00CAN worth of Definitive Technology speakers which he calims are the best in the world. Maybe you folk would have a comment on that stement!!!

You gotta love salesmen & politicians, God has a special place for them.

Yes I am a salesman and I have heard lots of DefTech speakers but to say they are the best in the world means this guy has listened to all the speakers in the world-NOT -

Enough ranting, sorry all

Fr Ray

How tall are you side walls? Pictures would help.
 
I thougt speaker sales folk HAVE listened to all speakers!
I think he did actually say "I've heard 'em all" :)

The side walls are 10 ft

1001534 looking from rear of church to front, organ is on the left,

1001530 looking from the front to the back

1001525 ceiling

1001527 rear of church from the very front wall

Floors are original pine circa 1870

We have two corners at the font of the church building to place sub(s) if needed.
 
The tapped horn as suggested by Moray James seems like the most bang for the buck. I haven't heard one and am basing on others comments. If you are interested I have a pair of kits for the Servodrive Contrabass Sub (not from the group buy), I bought from Servodrive. I picked up a few surplus motors for the sub. Contact me offline.

SMathews
 
It doesn't have to be round. The advantage of the round shape is you can get away with cardboard.
A square pipe still works, it just needs to be stronger. You may even be able to hide it as some steps or a large bench. I don;t recommend hiding it under the Altar, everything will rattle like little jackhammers when the organist hits 16Hz.

You may be able to fold it, I'm sure someone here can assist with the design.
 
Hello Fr Ray

I still can't find the pictures. I signed up for Yahoo and all it will do is let me upload pics I can't seem to look at anyone else's. I was thinking along the line of the El-Pipe-o project also. If you have an artist in you congregation who can do Faux painting they could be disguised to look like marble columns (see Fig.20 in link above). A pair of these with Mach5 MJ18's wouldn't cost very much and the base would be incredible. If you are thinking of a platform then check out this one. Acoustic Wave Canon :angel:
 
TwisterZ :
Did the link I have a few posts prior to yours not work?
I could email direct if you wish--great support at his site.

Also a strange situation. I had contacted the folks at SVS regarding two used 12 inch drivers from a SVS tube sub. Asked for the T/S numbers( I told him I was a priest and if he "confessed the numbers I coukld not tell anyone anyway!! :)
The response: "While we wouldn’t give you the t/s, we’ll do better. We’d use our own LEAP PCs to help you design the enclosure for your specific needs"

Will post what becomes of this offer. Will take the plunge shortly--on aproject or 2 so many subs....so little time (money :) )
Intersting how young folk at the parish are getting interested!
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.