or Connect
AVS › AVS Forum › Audio › DIY Speakers and Subs › Hey guys...we need a little rallying here...
New Posts  All Forums:Forum Nav:

Hey guys...we need a little rallying here... - Page 12

post #331 of 9846
Quote:
Originally Posted by ZilchLab View Post
Yes.
Was there a measurable difference in response, if so by how much, link?

Quote:
Originally Posted by ZilchLab View Post
If I were "fixing" them, I'd chuck them in a 4-jaw and part, turn off, or mill off the extra.
As would I, just don't assume others have these machine tools as well.

Quote:
Originally Posted by ZilchLab View Post
That's a secondary operation best worked around via other means such as the gasket, though.
I have not used a screw-on CD before, can you damage the CD by over tightening=compression at the throat, making the rear mating between the physical end of the WG and the CD thread shoulder critical to avoid crush? Otherwise, I would think a 1/16th off +/- via file, sander, something shouldn't be too much for the average consumer.
post #332 of 9846
The threaded "snoot" is usually part of the casting in these little guys, i.e., one-piece. That could be turned down a bit more, but I don't think anybody fancies the prospect of secondary machining compression drivers, either. I doubt Celestion would provide a custom variant except on large OEM orders, maybe....
post #333 of 9846
Sorry about that, back on topic.

The 15" EOS looks to be the choice of many, including the "either" votes.

How many votes are we looking for before we move forward with a specific design?

Which CD do you prefer to have this WG optimally matched to?

Who is willing to send money directly, or into an online escrow account to move this project to the prototyping phase?

What are your guys thoughts on having the flange and critical throat machined from aluminum and then cast into the horn? It may be possible to get away with a simple male mold and fiberglass/resin construction, may be a cheaper alternative for the first prototype or low #'s manufacturing.

What is the preferred material of construction and color for those interested?

Who would prefer to have an elliptical flange vs a rectangular? If we are going to pay to have a mold made and units run-off. Getting 20 ellipse templates cut out of 1/4" hardboard for use with a router guide bushing will be cheap in comparison.

Jzagaja, or somebody else with the capability, are you willing to complete the CAD/CAM model with the necessary throat and CD flange, as well as the horn screw flange?

What about adding any stiffening ribs at the CD flange to horn transition, also any stiffening ribs along the back of the horn wall for overall rigidity?




My answers:

CD- Whichever that is </=$200 and gives the most even FR and low frequency extension to achieve 1000hz XO.

Money- Will put $75 in escrow contingent on a spec prototype being completed.

Material- Aluminum mounting plate and throat with anything strong enough and a smooth surface finish for the rest.

Color- Black

Flange shape- Elliptical with router template.
post #334 of 9846
Quote:
Jzagaja, or somebody else with the capability, are you willing to complete the CAD/CAM model with the necessary throat and CD flange, as well as the horn screw flange?

Once we agree on EOS profile I expect a list:

Customer....Driver or holes sketch ....Color......alu or mdf flange (mounting plate)

I assume 25mm throat for fine tuning, white color, mdf flange, 100mm diameter without holes. Ribs aren't necessary - this is for homes use. Bitumen layer can be sprayed or brushed afterwards (not necessary).
LL
post #335 of 9846
Quote:
Originally Posted by LTD02 View Post

hi duke... as you know, there have been some quality control problems in the past with the eng-190. do you have a source that provides consistently good quality waveguides? some folks around here would like to experiment with it, but were turned off by the bad batch or whatever the issue was.

The last batch of ENG-190s that I got directly from DDS were excellent. Beautiful cosmetically, thick but not too thick fiberglass. I still have to grind the back of the flange flat and do some touchup here and there. Occasionally there are thin spider-thread cracks in the surface gelcoat, but they're easy to hide with a correspondingly thin sharpie. One slight issue was that the custom 8-hole-flange configuration I got did not have the 8 holes perfectly equi-distanant from one another, but that was not hard to work around. Unfortunately they don't photograph very well, or I'd post a link.

Now one of the problems you guys would have is, we don't know the generation of the stock that vendors have on hand. You can ask 'em, and make sure you have return privileges, or maybe even organize a group buy.

The DDS waveguide has a larger diameter "lip" than the Geddes profile. This means the on-axis dip is shallower, but also that pattern control degrades at a bit higher frequency.

Quote:
Originally Posted by ZilchLab View Post

The Celestion Nd thread-on doesn't quite completely seat in the Pyle or Dayton clones, but does in the original JBL PT version, which does not have the metal insert. How are you resolving that in production? I have suggested that a thin resilient gasket at the transition might be an easy solution.

[Think hose washer.... ]

I grinded down the backside of the first few Pyle horns, and then I forgot to do so on a pair and took 'em to an audio show and nobody (including me) heard anything amiss. When I got home I did a blind test and the difference was apparently inaudible. So now I don't worry about it. I end up doing some whittling on most of the horns in the throat area, as there's a little bit asymmetry in the mold. Also every now and then I get a horn with the threaded hole clearly off-center by a significant margin, and those get discarded because they'd be too hard to fix.
post #336 of 9846
It looks like a general design is pretty much agreed upon. Not sure how many more specifics will need to be ironed out. But it might be time for step 2.


I didn't think this was a group buy, but maybe it went that way. I thought we were going to agree on a design and then get a prototype made up? A group buy will only help a few people in a short time window, we need to figure out a longer solution for this problem and for more people. We need a lot, not just a few. No reason for designing anything if weren't talking about 10-20 people.

Jzagaja mentioned to me that it costs a LOT of money for shipping unless we do entire pallets, and even then, it gets quite expensive. Like $800 for just the pallet to be shipped to a port! I need to discuss this more with him though.

I told Penngray that it might make sense to see if jzagaja could make us a prototype if we agreed on what's needed. He knows how to model them and create the 3D file and he does great work. If he can't make us a prototype, then maybe I can pay him to do a very nice 3D file so that we can find someone here to make the prototype for testing. Making up a one off prototype would cost much more than his normal run of waveguides I'm sure, but it could be better than a 3D printer, or a milled prototype. In the end, it would likely about the same price.
post #337 of 9846
Thread Starter 
a concern is the size of the flare relative to the size of the o.s. horn portion. while it has been demonstrated that large transitions are superior to rapid transitions, i'm not sure what is "optimal" for this application. we want good pattern control, but also don't want to blow up the top end. my gut tells me there is too much real estate dedicated to the roundover in eos v1.0. just thinking out loud here...the proposed horn may actually be best suited for matching to a 12" drive. i'd like to see a little less roundover for the 15", so that we can maintain pattern control down to around 1.1khz or so and not go larger than 15 inches or so total diameter. i'd be fine with an 18" diameter horn, but that is getting too far out of the mainstream to be of value. 15" is the large end of the sweet spot here.

btw lurkers, latest poll in #326. please vote.
post #338 of 9846
Erich,

I was under the impression you were going to have this prototyped stateside, no? Are you not free to use the file provided? The conundrum is do you have a quick and dirty mold made from wood/foam so that a cheap and easy prototype can be made for testing, or do you go full gusto expecting it to perform as designed and make everybody happy.

Regarding it being a group buy or a marketed product, at this time I believe it should be looked at as a "group effort". Unless you're willing to risk the cash on a failed or potentially knocked-off product I figure it would be best to start small, and keep initial costs as low as possible. Counter to which would be paying large sums shipping product across the Atlantic. In addition if you're really thinking big then it should ultimately be infection molded. `

Ultimately some base number of potential customers has to be realized in order to price the product in the short term since the majority of the cost is going to be R&D/Protoyping.
post #339 of 9846
Quote:
Originally Posted by LBDiver View Post

Erich,

I was under the impression you were going to have this prototyped stateside, no? Are you not free to use the file provided? The conundrum is do you have a quick and dirty mold made from wood/foam so that a cheap and easy prototype can be made for testing, or do you go full gusto expecting it to perform as designed and make everybody happy.

Regarding it being a group buy or a marketed product, at this time I believe it should be looked at as a "group effort". Unless you're willing to risk the cash on a failed or potentially knocked-off product I figure it would be best to start small, and keep initial costs as low as possible. Counter to which would be paying large sums shipping product across the Atlantic. In addition if you're really thinking big then it should ultimately be infection molded. `

Ultimately some base number of potential customers has to be realized in order to price the product in the short term since the majority of the cost is going to be R&D/Protoyping.


Yes, the costs of making a prototype and getting it made up were discussed. The answers to your first paragraph were posted in the thread a few days ago, might have been last week, not sure. Injection molding was an option after that, but obviously it's expensive, so other ways need to be explored.

No design is going to make everyone happy, as stated earlier, this is like politics and religion. There won't be a definite answer for everyone, but that shouldn't stop us. Lots of people like Polk and hate Klipsch, and vice versa, but they both keep making speakers.

I have to send the file to someone to have it looked at, I'm not sure if it's what he needs or not right now. When I called him this week, he said his brother was just taken to the hospital but he would call me back in a couple days. Obviously I didn't want to push it on him at that point.
post #340 of 9846
I'd be in for whatever size, but I'd pay more for a larger horn than a smaller horn. I'm probably unique in that regard, but if I'm going to spend a decent chunk of change I'd like it to be closer to Porsche than Toyota if you catch my drift...even if it is less practical.

I'd say that for a smaller horn like the 15" EOS I wouldn't want to pay more than $100ea. I'd be more interested in something 18-20" myself to get pattern control down to 800-900hz as I've stated before. That would be worth maybe up to $200ea to me.

I do like the idea of buying a plug from someone and then creating molds from it in the US, if the source is fine with that. I think a poured urethane into a silicone mold would be fine. Injection molding is well beyond the scope of this project, IMO...unless Parts Express was interested in taking the lead. Has anybody thought about floating it by them as a Dayton product?
post #341 of 9846
Just to be sure we're on the same page here, when we say "15 diameter," what we mean is 15" WIDTH; it's an ellipse, and the design in-hand has a 10" vertical height with integral mouth roundover generating a 90° x 45° pattern.

My perception is that Erich H will be making a prototype of that for measurement and performance testing prior to committing to a small-scale production mold.

I doubt this would have any traction with Dayton without a proven design and demand....
post #342 of 9846
Quote:
Originally Posted by Erich H View Post

Yes, the costs of making a prototype and getting it made up were discussed. The answers to your first paragraph were posted in the thread a few days ago, might have been last week, not sure. Injection molding was an option after that, but obviously it's expensive, so other ways need to be explored.

No design is going to make everyone happy, as stated earlier, this is like politics and religion. There won't be a definite answer for everyone, but that shouldn't stop us. Lots of people like Polk and hate Klipsch, and vice versa, but they both keep making speakers.

I have to send the file to someone to have it looked at, I'm not sure if it's what he needs or not right now. When I called him this week, he said his brother was just taken to the hospital but he would call me back in a couple days. Obviously I didn't want to push it on him at that point.

Yeah I read the previous, hence my questions when the discussion turned to paying $$$ to ship a pallet across the Atlantic, probably just a mix-up. It seems I got lost between "we need a lot" and "10-20" Too me "a lot" is minimum 100 people, and since I assume most people will want a pair, were talking 200+ units. This quickly turns a $5,000 injection mold into a $25 or lower fixed cost per horn which is very reasonable, ultimately making these $60-75/piece items. Hence why I was trying to clarify the situation, ultimate consumer expectation's.

What seems most reasonable to me is to have someone with a quality wood CNC (not ShopBot or AXYZ) with a high Z axis (5"+) and have them create a 2 or 3 piece male mold with registration pin holes and then spin up a aluminum flange on a lathe so we can get a working prototype. If you were provided with a STEP file it shouldn't be a problem, it's a common 3D file format.

By "making people happy" I did not mean everybody, rather that the prototype performs to a high enough standard that the parties interested are willing to pay money to have a copy made for themselves. Bottom line scenario, I don't want to see you or anybody else left hanging with a large outlay for something that is abandoned/goes nowhere.
post #343 of 9846
What waveguide do you want?

1. Penngray - 15" EOS
2. LTD02 - 15" EOS
3. 3AMRecords - 15" EOS
4. Noah - 12" EOS (assuming it holds pattern control down to ~1.2 kHz or less)
5. Zilch - Minimum 12" EOS (+cab roundover) assuming there's minimal on-axis notch
6. Erich H - either
7. JoshK (AudioJosh) - either with preference for 15" EOS
8. Bwaslo - 15" EOS, but either ok. 1" exit CD.
9. DS-21 - depending on cost (too rich for my blood and the incentive to swap out the 12" Tannoy DC's gets markedly lower), 15" EOS, 1" exit and throat-matched to a known-good CD (don't care which: B&C, BMS, Beyma, etc.)
10. P Monger - 15" EOS
11. LBDiver - Whichever will lead to it actually being built (current 15"-EOS w/ roundover looks good)

I'm potentially interested in a pair of these, but it depends on what the group decision comes out being as well as price as shipping could easily be more than the WG's. 15" EOS would be OK.
post #344 of 9846
Thread Starter 
alpha niner, go ahead and add your name to the list. this is not a commitment list. it is a survey of which size horn would appeal to you.
post #345 of 9846
Thread Starter 
"Just to be sure we're on the same page here, when we say "15 diameter," what we mean is 15" WIDTH; it's an ellipse, and the design in-hand has a 10" vertical height with integral mouth roundover generating a 90° x 45° pattern."

+1

i still think the roundover/pattern control issue remains. the v1.0 mockup has a very large roundover. that limits the size of the o.s. part of the horn and thus the frequency where pattern control is held to. instead of a 5" radius roundover, perhaps something closer to 2" might be better???
post #346 of 9846
Quote:
Originally Posted by LTD02 View Post

alpha niner, go ahead and add your name to the list. this is not a commitment list. it is a survey of which size horn would appeal to you.

Well, I don't have the same level of interest as most others do so far as I'm confident the current projects will be long term keepers. My interest is more for experimentation.
post #347 of 9846
Thread Starter 
just for sake of comparison, does anybody know (or can somebody measure) the total width of the qsc 152i horn?
post #348 of 9846
Quote:
Originally Posted by LTD02 View Post

alpha niner, go ahead and add your name to the list. this is not a commitment list. it is a survey of which size horn would appeal to you.

Okay. In that case:
post #349 of 9846
[quote=A9X-308;19595889]What waveguide do you want?

1. Penngray - 15" EOS
2. LTD02 - 15" EOS
3. 3AMRecords - 15" EOS
4. Noah - 12" EOS (assuming it holds pattern control down to ~1.2 kHz or less)
5. Zilch - Minimum 12" EOS (+cab roundover) assuming there's minimal on-axis notch
6. Erich H - either
7. JoshK (AudioJosh) - either with preference for 15" EOS
8. Bwaslo - 15" EOS, but either ok. 1" exit CD.
9. DS-21 - depending on cost (too rich for my blood and the incentive to swap out the 12" Tannoy DC's gets markedly lower), 15" EOS, 1" exit and throat-matched to a known-good CD (don't care which: B&C, BMS, Beyma, etc.)
10. P Monger - 15" EOS
11. LBDiver - Whichever will lead to it actually being built (current 15"-EOS w/ roundover looks good)
12. 12" EOS mjg100
post #350 of 9846
Quote:
Originally Posted by ltd02 View Post

just for sake of comparison, does anybody know (or can somebody measure) the total width of the qsc 152i horn?

14"
post #351 of 9846
[quote=LTD02;19588909]you are saying that as long as it holds c.d. to 45 degrees, it is good.

the first time, my eye didn't catch that it was flat inside that region./QUOTE]

I missed it too; it does look very good out 45 deg.

jzagaja, what is the depth of your 15" EOS?

That's more of my concern w/bigger WG's than the width.
post #352 of 9846
Thread Starter 
thanks hg...so the 15" waveguide is pretty much in the same category as the qsc horn.

noah, 120mm (~4.75") is what is shown here. is that what you were looking for?
http://www.avsforum.com/avs-vb/showp...&postcount=200

"I missed it too; it does look very good out 45 deg."
thanks for posting this. nice to know that i was not the only one who missed it.
post #353 of 9846
Quote:


jzagaja, what is the depth of your 15" EOS?

12cm deep with roundover 12cm.
post #354 of 9846
Thanks, actually a few mm less than the XT1086.
post #355 of 9846
Thought some of you might be interested in this. Make sure you check the pics link and the PDF (second link).

Then have a read of this.
post #356 of 9846
Thread Starter 
noah, a few pages back, you asked how common it was for pro audio two-ways to cross too high. looks like qsc was thinking the same thing. they have released the k12,

http://www.qscaudio.com/products/spe...series_K12.php

which has directivity matching as explained here:
http://www.qscaudio.com/products/spe...re=directivity

for a powered speaker, with multiple rca and xlr inputs, directivity matched, $800 street price shipped, it looks like it is going to be among those to beat.

i couldn't find any frequency response or polar measurements, though it looks like they are optimizing for flat power response. nice.
http://www.qscaudio.com/products/spe...sic_correction

post #357 of 9846
Thread Starter 
alpha niner, nice links. the big electrovoice looks really nice to me. i checked and it was offered in 90x40. looks like it was knocked out in the final round. i'm still reading through it all.
post #358 of 9846
LTD02, thanks for the links.

Those are amazingly priced since they're powered.

I like the K12's 75 deg coverage, I'm trying to minimize early reflections from a side window.

I wonder how good the drivers are, though presumably the DSP helps a lot.

It's interesting that they all seem to have the same XO.
post #359 of 9846
Thread Starter 
"It's interesting that they all seem to have the same XO."

that is what i thought at first, but then i realized that they are compromising in the directivity control. the small driver has the widest directivity horn, while the largest driver has the smallest directivity horn. that is consistent with directivity matching, at least on some level.

"I wonder how good the drivers are, though presumably the DSP helps a lot."

at this pricepoint, forget about 4" voice coils and triple demodulating rings...they have to be mediocre drivers. but, mediocre drivers != mediocre speakers. with dsp optimized *power* response, they probably sound pretty good around the room. the f6 is about right for a ported thx crossed main. max spl is over 120db across the band. for a high passed main, so far, this speaker looks like a major WIN to me.

i can't believe that they are only $800 bucks...powered. (and that is with a six year warranty)
post #360 of 9846
You guys have been busy....get away for a weekend and there is so much to cover
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: DIY Speakers and Subs
AVS › AVS Forum › Audio › DIY Speakers and Subs › Hey guys...we need a little rallying here...