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bulding the ultimate diy system

Please let it run. It's a great case study for my ongoing research into online communication styles ad failures.
 
What happened to my post? I was saying it's not that bad a system idea just get the woofer-mid-tweeter and give one speaker a go.
 
Look everyone, Anjora may have bitten of more than he can chew but if he wants to build such a wideband speaker then that's up to him. We've let this become a slaning match, something we've always prided ourselves for not doing! Anjora made an effort to stop being so agressive and was actually getting somewhere. Some of the ultimate goals may be slightly unrealistic but I for one was enjoying the driver comparisons.

Stefan
 
There is a few weaknesses with my current design sush as vertical interference issues above 1500 hz, not sure if it's a real world problem. The centre to centre distance is 280mm with 120mm drivers.

with 2500hz XO the theoretical minimum angle is 20° (it's about the same between 1500hz and 3000hz) 4 drivers allow for smaller vertival distance but then there will be horisontal interference issues above 3khz.

john.luckins said:
Perhaps there are less controversial elements in the rest of this diy system that you are proposing Anjora. What do you propose for the amplification or music source. If you want 1Hz then you'll need to get the turntable suspension just right!

Joking aside, I'm interested in what you have in mind for these.

John
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Haha yes, i have actually considered getting a turntable due to loudness war but i started listening to high resulition audio instead, vinyl can reproduce higher frequencies than cd but there is a lot of ultrasonic junk aswell so it's probably a good idea to use a lowpass filter.

I havn't found the right amps and dacs for my system yet, johnw is working on some interesting projects which could be what i'm looking for. The subwoofers(later project) will neew class d amps, i have not decided if these amps will be diy.
 
So what bass driver above 50hz?
Powersoft or LabGruppen class D for subs-they come with DSP and will drive 2 ohm at 4k/channel all night long so you'd only need one per side.
 
With regard to tracks you believe have significant infrabass and ultrasonic frequency content, why not just find out where they were recorded/mixed/mastered and use their systems as a basis for your own?

Surely they must have equipment that covers the spectral extremes, or how would they know what they were hearing?
 
Profsparks said:
With regard to tracks you believe have significant infrabass and ultrasonic frequency content, why not just find out where they were recorded/mixed/mastered and use their systems as a basis for your own?

Surely they must have equipment that covers the spectral extremes, or how would they know what they were hearing?
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a bigger limitation is the microphone used, earthworks qtc-50 goes up to 50khz but most mics roll off much earlier. i guess the only way to be sure is to record myself using qtc-50 and a biquad filter to extend the responce to over 100khz.

they don't nessisary need to have speakers cabable of reproducing infrasonics, but it helps during mixing and eq process(if eq is used). a bigger issue is loudness compression, this is the primary reason why i listend more and more to high resulotion audio.

similar built http://www.audioexcite.com/?p=3736 with audiotechnology woofer and midrange, i will instead place two midrange units as close as possible to the tweeter, i will also only use 12dB/octave acuostic crossovers instead of 24dB/octave between the midranges and tweeter, i still not sure if audiotechnology c-quenze 15 sdkm or scan speak 12mu is the best choice for the midrange.
 
Agreed, there is evidence that ultrasonics can have an affect on our percieved auditory experience, but wouldn't extrapolating and synthesising HF an octave above a mic response that is already more than an octave above the arbitrary limit of hearing, add more harmonic distortion than present in a straight 20k low pass?

Sorry, but i don't follow the sub-sub requirement. If the tracks you want to play have infrasub content, then they must have been through systems that are capable of reproducing such frequencies, or how would the artist/engineer/producer know they were there in the first place, and what they would add to the experience?

Loudness compression and high resoloution audio are not mutually exclusive, but that's a whole other thread...
 
Profsparks said:
Sorry, but i don't follow the sub-sub requirement. If the tracks you want to play have infrasub content, then they must have been through systems that are capable of reproducing such frequencies, or how would the artist/engineer/producer know they were there in the first place, and what they would add to the experience?

Loudness compression and high resoloution audio are not mutually exclusive, but that's a whole other thread...
Click to expand...
they could simply listend live(if the music is acuostic), b&w 801 which is a studio speaker plays pretty low so the person doing the recording would still get a feeling for it.

or they could simply just keep what the mic picked up. in 1812 overture the mic is mized in digitally but they only need to adjust the volume then. it is true high resolution audio isn't free from loudness compression, but it's very hard to find newer CD:s that doesn't sound horrible.

in most tracks a single 18 inch subwoofer/channel with linkwitz transform would be enough to reproduce everything down to 1hz without severe distortion since the frequency components below 20hz generally is very weak. there is a few tracks where more subwoofers is needed to prevent the cone from bottening. I will compromise and be happy with 4...8 subwoofers per channel, it's not worth spending $3000 for just 3 tracks http://sound.westhost.com/linkwitz-transform.htm
 
You will note that the espaudio linkwitz transform circuit uses a 15Hz high pass filter. I wonder why?

Assuming that you actually believe anyone then, returning to the loudness issue......

Each 10dB increase in the Figure 1 curves represents the sound being twice or half as loud, because this is the way our hearing works. For example, to get a sound system to sound "twice as loud" according to listeners, the amplifier power must be increased by 10 times. Assuming the use of the same speaker system, a 200W (average) audio signal is perceived as twice as loud as a 20W signal, but a 40W signal is only 3dB greater - a just perceptible change to the listener. There are other (subtle) influences, but in general this is verified in controlled tests.
 
Add to this, even allowing for room gain each of 'those' bass drivers will be running at 98% distortion producing 93dB @15hz..
 
mudlark said:
You will note that the espaudio linkwitz transform circuit uses a 15Hz high pass filter. I wonder why?
Click to expand...
This is why i will built ny own circuits. No highpass filter will bu used to the woofers/subwoofers only shelving lowpass filters, sime class d amps also has highpass filters(usally without telling it). Using a highpass filter to a linkwitz transform is pure idiocity, not surpriced esp:s circuit does.
 
cooky1257 said:
Add to this, even allowing for room gain each of 'those' bass drivers will be running at 98% distortion producing 93dB @15hz..
Click to expand...

93dB is pretty high. With 8 bass drivers it's 111dB at 15hz, not sure if there will be any room gain @15hz though. http://www.avsforum.com/t/1314884/8x-18-lms-ultra-5400s-in-4-sealed-enclosures
1Xune.png

8 stereo integrity ht18d2 / channel could be just as good.
 
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