I'm still interested in the apparent 'free lunch' aspect of vented speakers. Is there a fatal flaw in there somewhere?
As I understand it, the output of the vent is delayed relative to the cone movement, leading to 'time smear' as Wikipedia describes it, and below resonance the bass falls off more rapidly than an equivalent sealed box. Are we absolutely sure that these characteristics are of no consequence when it comes to listener fatigue?
Did the same on a Commodore Pet, remember wanting to upgrade the cassette section to handle metal tapes that were new, maybe speed up the transfer or increase capacity, maybe both! LOL yes exciting times
Whoa, you had a Pet? We had phone modem dial up to some main frame. Print outs on thermal paper. Get them hot and they turned dark brown.
I feel old!
David
No free lunch. What is perceived as gain also increases group delay. Below port frequency total chaos and sharp roll off. I think this where an MLTL excels. Port is tuned to dampen the drivers resonance and the length determines the tuning. Easier room placement, smoother roll off and better dampening.
That won't work. You need to experiencing yourself with many type of fatiguing effect. There some that sounds like at the bottom of the ear, some sounds like at inner middle of ears and some other sounds like at the top outside the ears. They have different way to be minimized. Just like good imaging also many types. Sounds that feels at top of inner braind, also feels like at back of brain ,etc.
They aren't correlated by only harmonics, even they will show up for some harmonics combinations.
Here's a very nice test for audio: Sinatra with full band, something like Sinatra's Swingin' Session!!! The band has tremendous bite and punch, should have a huge, house fulling sound, the brass should cut and slice like the real thing, but Sinatra's voice riding on top of that should still remain like rich, smooth, dark chocolate, with all the nuances clear and refined as always. The 2 "sounds" balance each other, the contrast is dramatic and effective, and it's a tremendously satisfying experience to listen to - whether a system is capable of resolving those two elements cleanly is very telling ...
Many years ago a seemingly very impressive demo system at a hifi club day - top of line panel speakers, battleship valve amp, the works - I got them to play such a Sinatra CD -- and it was a pretty miserable attempt - it managed to get both the orchestra, and Sinatra, 'wrong' ...
Similar like what? What if instruments and vocal plays simultaneously? Shouldnt we be able to follow any sound source clearly?
I dont understand. Is this your imagination or knowledge i have missed? I understand about harmonics structure of certain instruments but not this ear and brain things. Am i the only one who cannot follow??
Not with the same gain or excursion or linearity. Plus with sealed GD rises higher up before the others.Of course, one can simply damp the vents and get much the same effect
I said damp not seal, but agreed. Many vented systems could use some vent damping though.
Since Karna and I grew up with this kind of music, it's a natural for us to listen to on a hifi system. It helps that Sinatra's orchestra was recorded on a big Hollywood sound stage, and the microphoning is simple, without the insane multi-mike level tweaking of modern classical recordings.
If a hifi system can't play a recording with realistic orchestra and vocal ... with one of the great singers of the century ... then something is terribly, terribly wrong with the replay system.
At a guess, the most common technical faults seem to be, in no particular order:
* Too many output devices, all finding their own Class AB cutoff point, and dynamic bias making the problem worse, not better
* Not enough phase margin in the feedback loop, so reactive loads from the loudspeaker and weird cables nudge the amplifier towards transient instability and longer settling times
* Intermittent slewing in the phono preamp, or input or driver stage of the power amplifier. Slow op-amps that operate in Class AB don't help. Hint: the 5534 is 30-plus years old, and is not the best op-amp out there
* Badly balanced speakers, with more energy in the 1~5 kHz region than 100 to 500 Hz region. This never sounds right.
* Tweeters crossed over too low, which leads to a kind of "nervous" sound as out-of-band energy pushes the tweeter into high IM distortion, depending on the musical spectra one or two octaves below the Fs of the tweeter
* Midrange or midbass drivers with rigid cones (Kevlar, carbon fiber, metal) and chaotic breakup regions in the 3 to 8 kHz frequency range and not enough crossover to reject the breakup zone
* Titanium dome tweeters. Titanium has about the worst self-damping of any modern diaphragm material, and there are some things that cannot be equalized away. Severe breakup is one of them.
* Acoustic phase angle between tweeter and midrange/midbass is more than 30 degrees, which gives a disjointed quality to the presentation
* Diffraction from horn-mouth edge or right-angled cabinet edge. This is more subtle than the grosser faults mentioned above, but it does degrade vocals, the sense of physical spaciousness and the sense of realism.
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I think i know what u mean. Unfortunately it is only a narrow band of midrange frequency. For expensive drivers this is even a given.
That just fatiguing and imaging, what it is feels like. For simplest fatiguing is feels hurt, and imaging is feels good.
I guess i know where you came from. I have long didnt get in touch with that kind of distortion.
I always test my system with listening to it when i go to sleep and observe my feeling when i wake up. Why? When you are interested in serious listening you will tolerate distortion but in certain situations you wont.
Just like when u have toothache u dont want to hear noises
I just woke up and still lying on bed listening to music rite now.
Im interested also as my best speakers have been vented. But i think this is more driver or Qts related. How can it be possible a low qts woofer better in sealed? Impossible ime.
About which one is more fatiguing i guess it depends on the overall design. Sealed can be more fatiguing as the mid bass tends to be unnatural.