DIY Waveguide loudspeaker kit

[markus76]

The point is that a multiple subwoofer optimization assumes a monophonic bass signal reproduced by all low frequency sound sources simultaneously. If one or more sources are excluded, optimization won't work.

[gedlee]

Originally Posted by PB2

How hard is it to understand that if you're building an HT with the intent of reproducing all the effects, then it should handle them all reasonably well?

Sure, I prefer music but I certainly understand the engineering challenge for HT, and even enjoy a decent HT experience.

Originally Posted by noah katz

You're saying that the use of deep bass is by nature gratuitous?

Maybe that's true; sound effects are for... effect.

Not ALL bass is gratuitus and a HT should reproduce effects to the point that they are necessary. But there is also "gratuitous" bass and LF effects that are neither necessary or audible. It's all about practicality and resonableness. My theater goes down to 20 Hz and it can produce pounding bass, but I don't go to extremes to get this and I'm not about to just to just to do 16 Hz on one or two movies. I've not seen a commercial theater that could do that either. Honestly, sounds like bragging rights to me.

[gedlee]

Originally Posted by markus76

The point is that a multiple subwoofer optimization assumes a monophonic bass signal reproduced by all low frequency sound sources simultaneously. If one or more sources are excluded, optimization won't work.

Markus, I will agree with "multiple subwoofer optimization assumes a monophonic bass signal", but this does not logically lead to "If one or more sources are excluded, optimization won't work." That's your hypothesis, and it is unproven. You don't know and I don't know if its any better or worse.

[jason_watkins]

The crazy thing about bandwidth is the trend is scaling absurdly fast. Maximum switched bandwidth changed from doubling every 2 years to doubling every 6 months in the late 90's. And we haven't even seen the commoditization of core routers that has happened with storage (RAID) and computation (parallel clusters).

My guess is somewhere past the next decade all connections will have roughly comparable bandwidth, whether it's the 6 foot cable between your disc player and your display or the 250 miles from your house to the nearest netflix data center. Latency is all that will matter.

To put this back on topic since I just sent in a deposit for some nathan's:

What's delivery trending to right now?

I recall there being a thread with a lot of great content from gedlee about finishing speakers. I can't seem to find it via search. Does anyone have a link? I'd like to do some tests on some small speaker stands I'm building next week.

[markus76]

Originally Posted by gedlee

Honestly, sounds like bragging rights to me.

I agree. Movie sound is mixed in studios that really are (smaller) movie theaters. Then there's remastering of movie tracks in normal studios like Mi Casa in LA for Blu-ray or DVD releases.
This makes me doubt that content below 20 Hz was ever intended to be heard on the final medium.

Best, Markus

[markus76]

Originally Posted by gedlee

Markus, I will agree with "multiple subwoofer optimization assumes a monophonic bass signal", but this does not logically lead to "If one or more sources are excluded, optimization won't work." That's your hypothesis, and it is unproven. You don't know and I don't know if its any better or worse.

Replace "won't work" with "might not work as intended". It depends on how many low frequency sources are used and how important each one is for optimization.
The point is to have an optimization that shows reliable results no matter how many subs are used or what programme material is played.

Best, Markus

[MethMan]

What kind of connection between AV receiver and DCX2496 you are using? Passive or active DI-boxes? 1:1 or 1:5 transformers?

[gedlee]

Originally Posted by markus76

The point is to have an optimization that shows reliable results no matter how many subs are used or what programme material is played.

Best, Markus

No, "optimum" is the best approach, not that it is perfect. You are talking about perfect and I am talking about optimum. Let's not confuse the two. We agree that what I do is not "perfect", I have not seen anything that says that it is not "optimum". I truely believe that there is no practical difference from the issue that you note because they are idealized extreme cases. But even one example of "false" is enough to elliminate the technique as "perfect". Its not enough to elliminate it as "optimum".

[markus76]

Originally Posted by gedlee

Blue-Ray.

I'm always shocked how desolate the audio scene has become:

Watch Johannes Mueller's presentation about "Pure Audio Blu-ray"? You'll find it at http://www.aes.org/tutorials/download/file.cfm?ID=129

They now started to talk about the use of Blu-ray for high quality (multichannel) audio. There's even a standardization project AES-X188. Can you believe this? When was Blu-ray introduced? Where were the AES in the standardization process? This makes them look like hobbyists.

[markus76]

Originally Posted by gedlee

No, "optimum" is the best approach, not that it is perfect. You are talking about perfect and I am talking about optimum. Let's not confuse the two. We agree that what I do is not "perfect", I have not seen anything that says that it is not "optimum". I truely believe that there is no practical difference from the issue that you note because they are idealized extreme cases. But even one example of "false" is enough to elliminate the technique as "perfect". Its not enough to elliminate it as "optimum".

I showed real examples from real DVDs. So I don't think I'm discussing idealized cases here.

And no, I'm not talking about perfect. Optimum is good enough this time

By the way, what "optimum" is your current optimization algorithm trying to achieve? Only smallest seat-to-seat variation or smooth frequency response or linear frequency response or any combination of the three?