cooky1257
pfm Member
There's a really interesting JBL tech research paper on port design too the results of which are incorporated into the latest Everests not sure there's much interest though.
Fast bass?
- Thread starter cooky1257
- Start date
There's a really interesting JBL tech research paper on port design too the results of which are incorporated into the latest Everests not sure there's much interest though.
cooky1257
pfm Member
dave
Plywood King
Most box loudspeakers sound just like what they are to me sort of "closed in", "stuffy" and well, "boxy" sounding. My SBLs seem to be pretty good in this respect being somewhat free of typical boxy colorations though what's there may be mostly boundary effects with wall placement. (Regardless, I'm not fooled as the music still sounds like it comes out of a box at times with the mid bass more so than the lowest octaves.)
Back to your point though, I can't say I've ever found a room good enough to make up for a speaker cabinet which resonates in the worst way yet I've been able to tolerate good low-resonace speaker cabinets in terrible rooms short of them being tiled shower stalls of course so it seems to me then that the speaker comes first and the room second. I'd say the acoustic (mechanical) aspects of speaker cabinet construction and room acoustics both probably deserve a lot more attention than they get from all of us regardless.
Just my two cents as a non-technical listener though...
regards,
dave
The quote in the original post illustrates that reviewers often don't know what the fock they are talking about.
The issue is whether the system (amp-speakers) has the ability to control the bass sufficiently to faithfully reproduce the timbre and speed (regardless of whether it is 'fast' or 'slow').
The issue is whether the system (amp-speakers) has the ability to control the bass sufficiently to faithfully reproduce the timbre and speed (regardless of whether it is 'fast' or 'slow').
Mike Reed
pfm Member
What IS 'fast bass'? Technically, I dunno, but consider this.
133kg each ProAc m/c speakers with ATC 9" bass units (2 in each). Just about as resonance free as you can get for a normal boxed speaker (cue weight !)
Quad 2905s. Same monoblocs (valved); same speaker leads; same everything else.
My aural perception is that the (admittedly reduced range) bass is quicker, and by dint of that, more natural and immediate. Less than milliseconds, possibly, but definitely quicker.
I'm sure there are many reasons for this, but cabinet integrity cannot be one such in my case, i.m.o.
Excuse my technical naivity, but surely moving a charged membrane has to be more efficient than moving a passive speaker cone. Or am I barking up the wrong tree?
133kg each ProAc m/c speakers with ATC 9" bass units (2 in each). Just about as resonance free as you can get for a normal boxed speaker (cue weight !)
Quad 2905s. Same monoblocs (valved); same speaker leads; same everything else.
My aural perception is that the (admittedly reduced range) bass is quicker, and by dint of that, more natural and immediate. Less than milliseconds, possibly, but definitely quicker.
I'm sure there are many reasons for this, but cabinet integrity cannot be one such in my case, i.m.o.
Excuse my technical naivity, but surely moving a charged membrane has to be more efficient than moving a passive speaker cone. Or am I barking up the wrong tree?
S-Man
StrivingON
Excuse my technical naivity, but surely moving a charged membrane has to be more efficient than moving a passive speaker cone. Or am I barking up the wrong tree?
Wrong dog and it's a rock
Efficiency is the sound energy output compared to the electrical energy input. Why would you want to include that in the discussion?
If the Proacs are ported then they rely on resonance to boost the bass response, by definition.
Your findings that they sound slower are 100% credible, from my POV.
Hoopsontoast
pfm Member
Open baffle speakers (DIY Hawthorne Audio Silver Iris Coaxials, Quad 57's and Magnepan MMGs) have had the 'fastest' bass I have heard at the expense of ultimate depth.
JemHayward
pfm Member
Speaker design is very odd... The speaker I helped design never reached the market, but we experimented with different cabinet shapes and sizes, and the changes we were expecting didn't always manifest themselves. For a given set of drive units the cabinet can make a huge difference to the result and we found that cheap to manufacture cabinets were difficult to get right, and the ones that sounded best were uneconomic to produce. In general (and its not somewhere where generalisations work) the stiffer the cabinet, the tighter, faster the bass would sound. Open baffles work really well, as there really is only one surface to deal with, but need to be infinitely large, and perfectly stiff. More frustratingly, changes in the HF response change perceptions of bass and vice versa, which even the acoustician in the team found surprising.
S-Man
StrivingON
I hadn't occured to me that the bass system I use will benefit in this way becaase it uses several medium sized drivers in small cabinets. I always thought the the huge improvement in bass performance, and overall sound, resulted from the near perfect transient response and being flat to 20Hz. Certainly it was able to improve the bass quality of a pair of ESL57QAs although rather less so than when crossed over to ported speakers.
What IS 'fast bass'? Technically, I dunno, but consider this.
133kg each ProAc m/c speakers with ATC 9" bass units (2 in each). Just about as resonance free as you can get for a normal boxed speaker (cue weight !)
Quad 2905s. Same monoblocs (valved); same speaker leads; same everything else.
My aural perception is that the (admittedly reduced range) bass is quicker, and by dint of that, more natural and immediate. Less than milliseconds, possibly, but definitely quicker.
I'm sure there are many reasons for this, but cabinet integrity cannot be one such in my case, i.m.o.
Excuse my technical naivity, but surely moving a charged membrane has to be more efficient than moving a passive speaker cone. Or am I barking up the wrong tree?
More tosh........
Stick to what you know about, Mike
Mark
S-Man
StrivingON
Decided to flip a couple of DIP switches and try -3dB at 10Hz today. Now that I have my "nearing-Xmax" LEDs working at least I know I'm not going to blow anything up.
Of course I cannot hear anything at these frequencies, but the point of the exercise is to minimise the phase shift at audible LF frequencies.
The audible result is subtle, indeed maybe I'm kidding myself....
Bass sounds ever so slightly less obvious, but tighter and faster. Also a fraction more tuneful. On a good live recording there seems to be a feeling of more space i.e. a larger acoustic.
All these types of changes were noted before when I went from ported 2-ways to this 3 way active bass system with -3dB at 25Hz. However those changes were not at all subtle! I guess it's a case of diminishing returns.
Of course I cannot hear anything at these frequencies, but the point of the exercise is to minimise the phase shift at audible LF frequencies.
The audible result is subtle, indeed maybe I'm kidding myself....
Bass sounds ever so slightly less obvious, but tighter and faster. Also a fraction more tuneful. On a good live recording there seems to be a feeling of more space i.e. a larger acoustic.
All these types of changes were noted before when I went from ported 2-ways to this 3 way active bass system with -3dB at 25Hz. However those changes were not at all subtle! I guess it's a case of diminishing returns.
S-Man
StrivingON
If you mean only listening to the LF then no, most music just sounds like some thumping noises.
To reproduce bass with the correct pitch and timing, the harmonics need to add together correctly - that's the whole point of extending the LF reproduction well below anyting that is on the recording.
To reproduce bass with the correct pitch and timing, the harmonics need to add together correctly - that's the whole point of extending the LF reproduction well below anyting that is on the recording.
S-Man
StrivingON
Depends how far it has to move.
demotivated
pfm Member
The higher speed a driver moves, the louder it is. Higher frequencies means it changes direction more often or abruptly.
The original article is pants. Reflex and closed box behave differently on transients which is a large part of bass music. A port does take time to start and stop resonating. This affects not only the sound output but the loading of the cone, since the internal pressure is higher when the port is singing. Most of the details are not well documented [that I have seen anyway].
The original article is pants. Reflex and closed box behave differently on transients which is a large part of bass music. A port does take time to start and stop resonating. This affects not only the sound output but the loading of the cone, since the internal pressure is higher when the port is singing. Most of the details are not well documented [that I have seen anyway].
