It was suggested, by John Hunter memory serves, that a powered sub can add 8-10 ms latency. His suggestion, in a surround system was to adjust the distances of all the speakers to compensate. Wondering what others might have to add?
Not sure what to reply to this, the basis seem overly simplistic and lacking several variables that actually come into account.
If you are talking about a relatively modern surround setup, most amplifiers come with perfectly useable mics and programs for calibration of sound and distances. Not saying this eliminates the problem, but in many cases it is a big help.
The idea that the "Powered" part of a sub can add 8-10ms delay in itself is preposterous.
But on the other hand if you are talking about any sort of eq or filters of any kind in the lower frequencies then YES, though 8-10ms seems like small change in that regard and the end number is likely significantly higher.
Then again, this can be measured and accounted for in most modern surround receivers, so what's the issue?
If you are talking about a relatively modern surround setup, most amplifiers come with perfectly useable mics and programs for calibration of sound and distances. Not saying this eliminates the problem, but in many cases it is a big help.
The idea that the "Powered" part of a sub can add 8-10ms delay in itself is preposterous.
But on the other hand if you are talking about any sort of eq or filters of any kind in the lower frequencies then YES, though 8-10ms seems like small change in that regard and the end number is likely significantly higher.
Then again, this can be measured and accounted for in most modern surround receivers, so what's the issue?
Generally not my experience, especially calibrating a sub. Haven't used every system available, never used ARC, but perhaps they were adding the "latency".
Actually hadn't consider that possibility, just wrote off what appeared to be inaccurate results.
In the "hi end" audio retail world filters, PEQ etc. seems the norm.
I meant for adjusting delay of the other speakers, seems much easier than moving speakers around seemingly at random...
You misunderstand: EVERYTHING messes with group delay (and thereby phase).
If you have a closed box subwoofer EQ'd to give the same response as a ported subwoofer you will have the EXACT same amount of group delay at the same frequencies. It does not matter if it is a room mode or whatever else may be the cause, I repeat: EVERYTHING messes with group delay.
Again, merely stating that "a powered sub can add 8-10 ms latency" is absolutely ridiculous. The power itself does nothing (except gradually increase thermal compression over a certain figure), unless there is a filter or EQ influencing either the power or the efficiency of the subwoofer.
Do note that I count vented designs as part of the whole "eq business", it really does not matter where you change the response whether it is by design or by DSP majick, it is merely by choice which compromises you are willing to accept.
Sound like rubbish to me, or perhaps something is misunderstood or not communicated correctly. What is so different about a "powered sub" compared to any other sub, or woofer for that matter when driven by a separate amplifier? Maybe you are talking about GROUP DELAY? The growing group delay is inherent to and caused by the highpass character of the response of the woofer or subwoofer (a result of its totally normal phase response). Also, it's important to understand that the group delay is not constant but increases as frequency decreases. It can be even more than 10msec but it's not something you need to or should "fix" or you will mess up the phase relationship at the crossover point.
Also, with the speed of sound being what it is, 10msec amounts to 3.45 meters, or about 12 feet. I hope you have a very large listening space available if you are going to reposition things that far! 😵
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From my view answer must be a clear yes.
Then off course it depends what amp is used.
If using plateamp with NO dsp, latency should be negligble.
If using plateamp with DSP, we have more things that I know of, but DSP always adds some latency. Conversion of samplerate, processing etc... Hypex Fusion on digital input has 1.8 latency. Then some miniDSP have around 3 ms. Then you add filters and have more latency.
I feel this is another pointless, technical debates. Bass is woolly, slow, and invariably resonates. It travels through different mediums at varying speeds. The bass moving through the air will not reach you ears at the same time bass moving through solid structures reaches your a$$.
DJs cannot mix using bass or even kicks. They rely on sharp sounds high hats and snares.
DJs cannot mix using bass or even kicks. They rely on sharp sounds high hats and snares.
Not trying to debate anything, just wanted confirmation. When setting up a surround sound system speaker distance is either manually input or determined by Room Correction. The suggestion made by John Hunter was to adjust the distances of speakers to account for an 8-10' allowance for sub latency. Wheteher or not it is meaningful to the end user is debatable, but not the point here.
The 'latency' word threw me off for a minute, i.e. were'e normally 'talking' time delay, which is ~1.13 ft/sec, though historically regardless of where the sub was if not next to the mains, then 'we' just reversed the wiring since 2nd order XOs were the norm regardless of the XO point.
Anyway, 10 ft/1.13 = 8.85 ft/sec or x0.3048 = ~2.7 m/s, so measure horizontal 'line of flight' to get a plenty accurate enough delay if using other than 2nd order.
Anyway, 10 ft/1.13 = 8.85 ft/sec or x0.3048 = ~2.7 m/s, so measure horizontal 'line of flight' to get a plenty accurate enough delay if using other than 2nd order.