Focus 140 vs. Special 40
I advise OP to take a closer look at possible mods to reduce the resonance coming out of the port. Focus 140 woofer is smaller than Special 40 but I guess a better sounding loudspeaker with comparable woofer low end output, for considerably less money.
I advise OP to take a closer look at possible mods to reduce the resonance coming out of the port. Focus 140 woofer is smaller than Special 40 but I guess a better sounding loudspeaker with comparable woofer low end output, for considerably less money.
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OK, once again!
I am a retired Bell Labs Engineer.
Talk for a minute about spectral purity.
I was surrounded for decades with the most sophisticated test equipment in the entire world.
I really am sick and tired of you purists mocking those of us that experiment!
Think for just a brief moment about spectral purity!
If you are NOT a musician; you will NEVER understand!
The fact of the matter is that every capacitor, inductor and resister in the crossover can make a HUGE difference in sound quality!
Just image what a real, live acoustic concert sounds like in real life.
I have enough knowledge and experience to dispel the so called experts in the speaker design community! Listen to a musician; listen to a retired Bell Labs Engineer!
I don't care what you have been told in the past; premium crossover components can make a VERY huge and significant difference...end of the story; I have more first hand knowledge and experience than 1000 of the skeptics put together!!!
I am a retired Bell Labs Engineer.
Talk for a minute about spectral purity.
I was surrounded for decades with the most sophisticated test equipment in the entire world.
I really am sick and tired of you purists mocking those of us that experiment!
Think for just a brief moment about spectral purity!
If you are NOT a musician; you will NEVER understand!
The fact of the matter is that every capacitor, inductor and resister in the crossover can make a HUGE difference in sound quality!
Just image what a real, live acoustic concert sounds like in real life.
I have enough knowledge and experience to dispel the so called experts in the speaker design community! Listen to a musician; listen to a retired Bell Labs Engineer!
I don't care what you have been told in the past; premium crossover components can make a VERY huge and significant difference...end of the story; I have more first hand knowledge and experience than 1000 of the skeptics put together!!!
For what its worth I 100% believe you and thank you for all your help and suggestions! Haters gonna hate...
Cheers
Kawi, thanks for the photos. I would check if the internal walls were covered with bitumen pads, and at the same time perform the knuckle rap test. The sound of it should be rather "dead". If there was no bitumen by default, I'd consider getting some, like the self adhesive ones you would see used in automobiles. The resonance garbage coming out of port is likely an airborne resonance that calculates roughly to the internal depth measure. Anyway, the cavity behind the woofer should be filled with poly stuff (cabinet damping material) in such a way (neither too much, nor too little) that the woofer still has some free space to breathe to the port and suppress the resonance completely. The result is best confirmed by measuring, and listening of course. I use stuff that can be bought at upholstery supplies, looks like a poly rug 1" thick and can be easily made to a roll and stuck in the enclosure to fit tightly, without adhesive.
Yes it can, but if that's not the problem then no amount of component swaps will solve the problem.
Absolutely true! However, if the drivers are fully capable of "high resolution" let's call it; then they deserve high quality crossover components. You wouldn't put a cheap, 4 cylinder engine in a Corvette. You also wouldn't put a Corvette engine in a Yugo or similar either.
Bell Labs used to have a saying: A perfect amplifier is a straight wire with gain. So, imagine the perfect crossover having perfect components. No such thing obviously but, what you can imagine if you looked with a very high quality O'scope and Spectrum Analyzer at the waveforms and spectrum, no part of the original signal would be altered by the crossover other than what it is intended to do (i.e. filter the different frequency bands). Think harmonic content, musical overtones, etc. These are very complex waveforms. The idea is to preserve these signals intact...spectral purity I call it.
Premium components do, in FACT, a much better job of preserving the original signal. Inferior components will "smear" and distort these signals. What you get is a "congested" and "confused" sound quality. Again, there are diminishing returns; don't put a $100 capacitor on a $20 tweeter or midrange; it won't help any.
To post #56: an average 50 cent Wima MKP cap measures way better than any "premium audio grade" PIO rubbish. Apart from that, I don't know what you did at Bell Labs, but as an engineer you understand, that EVERY crossover apart from the 1st order series distorts the signal? No matter how much you pay for the parts.
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Relative high efficiency, low linear (altough this can be corrected) and non-linear distortions and low mechanical resistances for example.
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