or Connect
AVS › AVS Forum › Audio › DIY Speakers and Subs › 4 Pi vs DIY Sound Group's Fusion Sentinel 15"
New Posts  All Forums:Forum Nav:

4 Pi vs DIY Sound Group's Fusion Sentinel 15" - Page 5

post #121 of 297
I really think what he says makes a lot of sense. The H290C is like twice as long so its peaks are twice as low. That puts the top one at the bottom of the range of the H290C, and the others are below that where it isn't seen. I believe that's the point.

The SEOS may be less affected by its bottom peaks when some drivers are bolted on, but I think Wayne's point is it has the tendency to peak at 2k and 4k because of its length. Could be that's what Bill's charts show. There are more than one from Bill that show it, after all, and Bill is no rank amateur.

That's why I am inclined to also think Brad's measurement was actually telling you true info. It matches exactly with Bill's. I don't think it was a mistake in measurement, but maybe a mistake in driver choice or whatever.
post #122 of 297
Ash, I'm not going to explain to you again. Back off on the SEOS bashing. I've wasted enough time trying to set the record straight. It's obvious who you are. Screw off.

BTW SEOS >>> H290C
post #123 of 297
Bashing?

I thought we were actually starting to have a conversation.

Guess not.
post #124 of 297
The longer this thread goes on, the worse Wayne looks and the more obvious his sour grapes are...
post #125 of 297
Obviously a one way conversation cause you're not listening to what I'm saying.
post #126 of 297
At some point over the next few months if there is a nice weekend when I don't have anything going on I plan on doing a waveguide shootout. On axis/off axis response, off axis polar sonograms...lots of data. All will be mounted to a large baffle about 4' x 6' and measured outdoors at a distance of 1m and possibly a further distance out as well.

Waveguides will include SEOS-12, H290c, QSC, Dayton H512, EOS-10, EOS-8, EOS-6, Denovo DW-854B, DW-774s, DW-62s. Threaded waveguides will use the DNA-150, Bolt on waveguides will use the DNA-360.

If someone wants to send over a waveguide to be included in the shootout feel free to do so. I will start a thread for this soon.

Since I have both the SEOS-12 and H290c now here is just a simple indoor on axis response with the DNA-360, Measured with the Dayton UMM-6 and using REW. 1/48th octave smoothing applied since these were indoor measurements to clean up some noise. The outdoor measurements should make things much cleaner. I would not trust a comparison of two different waveguides if they were measured at different times by different people with a different measurement setup and using different CD's (even if the same model since there is such a thing as unit to unit inconsistencies).



Matt
post #127 of 297
Quote:
Originally Posted by mtg90 View Post

At some point over the next few months if there is a nice weekend when I don't have anything going on I plan on doing a waveguide shootout. On axis/off axis response, off axis polar sonograms...lots of data. All will be mounted to a large baffle about 4' x 6' and measured outdoors at a distance of 1m and possibly a further distance out as well.

Waveguides will include SEOS-12, H290c, QSC, Dayton H512, EOS-10, EOS-8, EOS-6, Denovo DW-854B, DW-774s, DW-62s. Threaded waveguides will use the DNA-150, Bolt on waveguides will use the DNA-360.

If someone wants to send over a waveguide to be included in the shootout feel free to do so. I will start a thread for this soon.

Since I have both the SEOS-12 and H290c now here is just a simple indoor on axis response with the DNA-360, Measured with the Dayton UMM-6 and using REW. 1/48th octave smoothing applied since these were indoor measurements to clean up some noise. The outdoor measurements should make things much cleaner. I would not trust a comparison of two different waveguides if they were measured at different times by different people with a different measurement setup and using different CD's (even if the same model since there is such a thing as unit to unit inconsistencies).



Matt

That would be pretty cool Matt. Do you ever feel we spend our time doing measurements, just for the sake of doing measurements, lol.
post #128 of 297
Thank you! That's the best comparison yet. And goes to show all the BS Wayne dropped in his thread was based on inappropriate information, which as I've said, he knows better.
post #129 of 297
Just you wait for those off axis polar comparisons that is when things are going to get interesting!
post #130 of 297
That does look good and I see no obvious peaks in either curve.

I agree this is probably the best comparison I've seen, since it is side by side with the same gear attached.

The H290C still appears to be smoother to my eyes though. I believe I made the right choice.

I also still wonder about the myriad measurements I've seen. It is confusing.

Am I still going to have to endure attacks and mudslinging for saying that here?
post #131 of 297
Quote:
Originally Posted by Ash R View Post


Am I still going to have to endure attacks and mudslinging for saying that here?

Are you goading for that?
post #132 of 297
Matt,

Good to see you here
post #133 of 297
Quote:
Originally Posted by zheka View Post

Matt,

Good to see you here

He'd probably have more time to post if he wasn't so busy reading my endless maniacal PM's. cool.gifbiggrin.gif
post #134 of 297
What is the difference between a current source and not? I see it mentioned as a reason for peaks. Evidently Parham believes that is key to exposing the standing wave modes.

Anyone here know what that means?
post #135 of 297
Absolutely, I concur. Thank you mtg90 for offering to do this testing. Should be very informative!

I hate to ask but would also hate to leave anything out. Would you please run one extra test for each waveguide? Test each with a current source to show where standing waves are. I guess that's possible, isn't it? It is a test mode, right?
Edited by Ash R - 4/23/13 at 11:46pm
post #136 of 297
Quote:
Originally Posted by mtg90 View Post

Just you wait for those off axis polar comparisons that is when things are going to get interesting!


^this. On axis performance is only a fraction of what makes a waveguide, a good one. Thats the whole point of making controlled directivity speakers IMO.

BTW when that thread(waveguide comparo) opens somebody link me if i dont see it, this is gonna be G rated compared to that flame fest, especially once actual data gets thrown into the ring.
post #137 of 297
Quote:
Originally Posted by Ash R View Post

Absolutely, I concur. Thank you mtg90 for offering to do this testing. Should be very informative!

I hate to ask but would also hate to leave anything out. Would you please run one extra test for each waveguide? Test each with a current source to show where standing waves are. I guess that's possible, isn't it? It is a test mode, right?

Are you 'asking', or 'telling'? Reason I ask is that you are trying to 'propose' a testing regimen which will be clearly advantageous to one waveguide over another, in one specific area you have already claimed supremacy.

To casual observers, it appears you have said you have made the 'right' choice already. Why the measurement shoot out then? To reinforce your choice? To further denounce a project by amateurs, for amateurs?

This is all very suspicious. According to my best recollection, once upon a time there was (and still is) a terrific speaker company that went above and beyond to make quality speakers while educating customers far beyond any expectation, with terrific white papers, advice on crossover design on many forums, etc. Then E-Waves came along, and Zilch started using some of these crossover ideas to upgrade older speakers to waveguide goodness with off the shelf waveguides. While cheap to obtain through QSC & JBL at first, these waveguides became more expensive and harder to obtain.

A collaborative effort materialized which created SEOS to make a waveguide for the DIY community, which has been quite well received by most, and available at a terrific price. PRO BONO, designers have stepped up to put forth designs. More and more build threads arise.

Not surprisingly, the H290C and SEOS are inevitably compared, starting a sh*tfight of epic proportions, with most of the aggression coming from the established, for profit company. Some behind-the-scenes dirt is flung, and there appears to have been some disagreement which is difficult to quantify due to the nebulous nature of the 'dirt'.

The conclusion from the above information is simple. Someone's wallet is getting lighter, and I smell a sock-puppet by strict definition or by proxy. How sad.

I have no dog in this hunt, and I believe both sets of speaker designs and their respective waveguides have tremendous merit. That one set of designs materialized out of an all amateur collaboration is a very special thing. That they perform well even better.

The shoot out will be very interesting.


JSS
post #138 of 297
Spot on. And that's how the rest of us reading this see it as well, I'm sure.
post #139 of 297
Preorder for the plastic SEOS-15 coming up this week. I finished taking pictures of all the big give aways that I had sitting around. We're ready to rock and roll on another one.

It's raining today, so I will have a good deal of time to start getting caught up on packaging. If there's time, I'll start working on the preorder page.
post #140 of 297
Quote:
Originally Posted by yelnatsch517 View Post

you are comparing a profit business with a nonprofit organization.

Was going through the recent discussion here. I am not pro/con either side, The SEOS option wasn't on the table when I built my speakers and today it would be hard to pick one. But to set the record straight of Wayne's "profit" business. He makes his plans available to the DIY crowd free for the asking including the crossover schematic. You can spend hours sourcing all the components and waiting for sales on the components like I did. In the end I think I saved about $150 per speaker versus his kit with assembled crossovers, mostly because of a fourth of July 20% off sale on the woofer. Even though I didn't spend a nickel with Wayne he answered every construction question I had on his forum and didn't hold back any secret sauce. Not much profit in that.

His business model is what many have proposed that the DIY Sound Group head toward to insure sustainability. That being to add something to cover labor costs and overhead. I see that assembled crossovers and cabinets are in the future for DIY SG and that option is very welcome.
post #141 of 297
So does anybody here know what a current source is and why it matters? I don't understand that part. I only know it is cited as the explanation but I don't understand why.
post #142 of 297
Also want to set the record straight here. I respect the advice from Parham, mostly because the fruits are a great sounding speaker. However, to say that makes me his puppet is insulting. Those of you leaning towards SEOS have been the aggressors IMO. I don't see any Pi Speakers proponents doing any name calling here.

If none of the SEOS people care about internal reflections, fine. I personally do. The whole point of the waveguide approach for me is to reduce reflections and HOM. It makes a cleaner sound and has less horn honk.

If the current source measurement shows internal reflections, it seems to me it would be included in any test regimen comparing waveguides. That's why I keep asking about it. I wonder if that's what it does, or if I have misunderstood. It looks to me like that is what Parham says, and I wondered what others thought about it.
post #143 of 297
Ash, first I'd just like to add that I believe the SEOS is smoother based on Mtg's results. The only advantage I see with the h290c is output. You preferring the on axis response of the H290C is just fine though, we welcome that. But as a speaker designer, I look at those two responses and my immediate choice is the SEOS. Perhaps if I was designing for pro use I'd take the output of the H290C, but for in home use, I'd take the refined one.

As for current source, I didn't catch that in Wayne's post but I assume he's talking about a current amp rather than voltage amp. I doubt we're going to go out of way to use a current amp to test the waveguide as nobody uses those. And I'm not sure it would show anything anyways. I can't see how it would show reflections. It would probably show peaks at the impedance peaks, of both waveguides. But what's the point of that.

Perhaps that's not what Wayne was talking about. Either way, your looking for something that doesn't exist. The SEOS was designed to reduce HOM and reflections and get a perfect match at the throat for the de250. Others did this, I admittedly know very little about waveguide design.
post #144 of 297
Aweso
Quote:
Originally Posted by Erich H View Post

Preorder for the plastic SEOS-15 coming up this week. I finished taking pictures of all the big give aways that I had sitting around. We're ready to rock and roll on another one.

Awesome! I look forward to seeing all the 15" designs smile.gif
post #145 of 297
According to mtg90's measurement, the H290C is almost perfectly flat from below 2k to above 10k. The SEOS varies 5db over the same range. Even you yourself admitted designers EQ that 4k peak. I don't fully understand the current source and impedance matter, but doing some google searches, I see impedance charts are sometimes cited when searching for reflections. I am guessing that's the point.
post #146 of 297
Quote:
Originally Posted by Ash R View Post

Also want to set the record straight here. I respect the advice from Parham, mostly because the fruits are a great sounding speaker. However, to say that makes me his puppet is insulting. Those of you leaning towards SEOS have been the aggressors IMO. I don't see any Pi Speakers proponents doing any name calling here.

Do we really need to start making a running quote tally of all your attacks against SEOS, vs. any attacks against Pi whatsoever? The only record needed to be set straight is your own. Ignorance is bliss.

I personally don't find the 4 Pi to be very compelling compared to a SEOS kit. The difference between the two would be negligible, but the price is not.
Edited by bhazard - 4/24/13 at 7:04am
post #147 of 297
Stating a preference is not an attack. Quoting a reference is not an attack. Describing a response curve is not an attack. This is a thread about one versus the other, and I've merely stated my preferences and why. For this I'm called out every other post. It's uncalled for and rude.
post #148 of 297
Can we agree to limit our comments to speaker properties please?
post #149 of 297
Ash, the sub 2khz region is the most important for design. Eq is easy. I wouldn't want to deal with that kick in the response below 1khz. My personal SEOS speaker crosses at 900hz, the H290C would make that difficult. The H290C would also need some eq, no fooling anyone with that.

The final result is what matters anyways.

I don't see how current sources would reveal reflections. What a current source would do though is drive more power into higher impedance than a voltage source. What's the point of that. No one uses those.
post #150 of 297
Ash R, both graphs show a +/- 2.5 dBs graph, you are seeing something that is not there. We can not hear this well anyways. If you think that a speaker with a DE-250 and 2226 is the best speaker ever you need to listen to more speakers. Maybe rather than putting down the SEOS waveguide you should hear one first. If you think using a DE-250 with 2226 and SEOS waveguide will make that big of a difference then you are biased.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: DIY Speakers and Subs
AVS › AVS Forum › Audio › DIY Speakers and Subs › 4 Pi vs DIY Sound Group's Fusion Sentinel 15"