Powered speakers show audiophiles are confused


17 of 23 speakers in my studio and home theater systems are internally powered. My studio system is all Genelec and sounds very accurate. I know the best new concert and studio speakers are internally powered there are great technical reasons to design a speaker and an amp synergistically, this concept is much more important to sound quality than the vibration systems we often buy. How can an audiophile justify a vibration system of any sort with this in mind.

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There is an old rule in recording called the 3 to 1 rule and it means the distance between the source and first mic is 1 the next mic should be 3 times that distance if you want less phasing.

 

To me, this rule (guideline) would factor around the typical fundamental tones of what you are recording, with the fundamentals being much more narrow than the extent of harmonics. With a speaker, and each driver working over a defined range, pointing in a specific direction, with the listener assumed to be at tweeter level, the problem would be more bounded. Remember MTM falls apart in the vertical direction if you are too far off axis.

 

@mijostyn Very good points, especially about the AES inputs, I'll look into that.

So I finally got everything working with my Genelec (analog speaker inputs) system and I was very happy even though the speakers have not been time aligned, I was playing test tracks and different surround sound formats for about 6 hours. Then I listened to my 2.2 system and there was no comparison the 2.2 was so much better, I mean better in a way that was not more accurate but better in a way that was nice to listen to and magical. Subs make all the difference I was very unhappy with my Paradigm 9hs until I bought the separate subs. The 9hs do have balanced Sub drivers but somehow on mine they were very unimpressive even with an adequate 700W amp in each cabinet. The external subs have a 3kW amp and shake the house that's important good base needs to be felt, I spent another 15k on nearly 40k speakers to get the bass right I'm so glad I did.

I think subs can be used in a square cabinet because the length of the frequencies are so long there will be no interference internally. Of course there are the old formulas that are ratios of speaker volume SPL of Frequency and volume the smaller the box the more power you need. 

@donavabdear , I was thinking about getting the new Jim Fosgate designed tube headphone amp The Aries from Black Ice audio which was demoed at this past CEDIA. They don’t have a price yet or a firm release date. I really like my Sony SACD/CD/Blueray player and wanted to try out their reference Signature line. I will likely get the matching headphones after I try it out as a DAC and a preamp. The DAC is a custom field programmable gate array and should be quite interesting vs the ESS and AKM DAC’s out there. This is why it has some of the features you don’t see on most DAC’s like the DSD remastering and higher bit rates on PCM:

DSD native (up to 22.4 MHz) DSD DoP (up to 11.2 MHz) PCM (up to 768 kHz/32 bit)

The fact that it has headphones designed to match the amp was a plus.

 

@donavabdear , My system is really very simple. I have a digital preamp that takes digital inputs from a universal disc player, the TV box and a Lynx Hilo. Connected to the Hilo is my phono stage, an Apple Mini, the Apple TV box and the Sonos connect. The Connect is hooked up to a very powerful router along with the Apple TV box. All the processing is done in digital. The processor is managed by a PC not the Apple mini which just plays music from a 6 TB hard drive. The processor has 4 DAC channels that power two speaker amps and two sub amps. The Hilo is a studio ADC/DAC mixer of amazing capability. There is nothing on the consumer market like it. As soon as it is released I will be getting a DEQX Pre 8, a full digital preamp with Room control, EQ and a 4 way crossover. It have 8 DAC channels. I may add ribbon tweeters to my ESLs.

As far as subwoofer enclosures are concerned a square or rectangular box is the worst design. The air within the enclosure is a spring. In the old days this was called acoustic suspension and like any suspension it has a resonance point. There are no standing waves within the enclosure. The enclosure wants to expand and collapse. Each size panel now has it's own resonance point as they flex and that resonance point can be up in the midrange!  Put your hand on the enclosure while the sub is handling heavy bass 30 Hz at 90 dB.  First put your hand on a corner. The vibration you feel there is the enclosure moving back and forth from the Newtonian forces generated by the driver. Next put your hand in the middle of one of the sides. Here you feel a combination of the enclosure moving back and forth along with it expanding and contracting.  A cylindrical enclosure is inherently stiffer and will be very resistant to compression and expansion. It will still move back and forth to Newtonian forces unless you mount an identical driver on the opposite side and drive it in phase with the front driver. This is called a balanced force design. You would have to double the enclosure volume resulting in a larger subwoofer but with the right modern subwoofer drivers you could still limit the size to 2 cubic feet excluding the volume of the drivers about another cubic foot. 3 cubic feet is not horrendously large.