Want some really 'true' sounding cabinets

[Arjank]

Once you dial in the voicing of the head, the electronic quirks of an electric bass, that literally doesn't have a 'true' sound (what is the sound of an unamplified EB, or for that matter, a DB with a pickup?!?), and then finally get on a gig, where the room acoustics vary massively every night (versus putting, for example, a stereo system in a fixed listening location), the concept of 'true' or flat or whatever totally goes out the window.

I'll get your point, but....
An acoustic guitar, piano, trumpet will ALL sound different when the room acoustics vary but STILL you can hear it's characteristics.
If I use my cab on whatever stage I'm on or room I'm in I still hear that characteristic sound of my bass. If I had a mediocre sounding cab I definitely would not hear this.
I'm a strong advocate of a "flat" or "true" sounding system. But "true" doesn't necessarily mean "flat". There are a lot of loudspeaker systems for hifi that are far from flat but do sound very realistic and true. A flat response is just one (but important) parameter of how a speaker system sounds.
I think a lot of people are in shock how "acoustic" their bassguitar sounds when played through a very well designed loudspeaker system.

 

[Arjank]

I don't understand how this relates to what i said. All i said is: you will never, ever have the same exact 100% acoustic sound when playing through pickups, an amp and a cab. However you can get them to be the most transparent possible.

Why should you want the "acoustic" sound you hear when you pluck your bass unamplified?

 

[KJung]

I'll get your point, but....
An acoustic guitar, piano, trumpet will ALL sound different when the room acoustics vary but STILL you can hear it's characteristics.
If I use my cab on whatever stage I'm on or room I'm in I still hear that characteristic sound of my bass. If I had a mediocre sounding cab I definitely would not hear this.
I'm a strong advocate of a "flat" or "true" sounding system. But "true" doesn't necessarily mean "flat". There are a lot of loudspeaker systems for hifi that are far from flat but do sound very realistic and true. A flat response is just one (but important) parameter of how a speaker system sounds.
I think a lot of people are in shock how "acoustic" their bassguitar sounds when played through a very well designed loudspeaker system.

+1 With EB, flat is a meaningless concept, since virtually no amplification system is flat, and most EB bass pickups (and DB piezo's) have a strong voice. It is all about the mix and match. Some typically (or even significantly) voiced components combined into a rig can actually result in a more even tone, and more transparent reproduction than a more widely voiced and/or 'flat on the scope in an artificial setting' cab combined with many heads and basses, etc.

Not so simple IMO. I think another confusion is people who listed to recorded bass tones they like on CD's through a good stereo. While that stereo, dialed into a fixed listening location, often in a very good sounding room, can be designed to very accurately reproduce the recorded input, often they are reproducing a bass tone that came from a voiced amp, or other tone shaping in the studio. Much better to really 'get a tone in your head' and then find an ENTIRE signal chain that can get you relatively close to that without a lot of drama, knob twisting, external EQ, etc., etc. IMO and lots of IME on this one.

When you roll in the concept of 'midrange character/distortion' levels, things get even more crazy, since that is a dimension and spec of a speaker that most don't talk about (Duke and Alex are wonderfully starting to build cabs now that are still reasonably even, but that also 'allow/design in/expertly voice' some of these other dimensions that make a bass sound 'good' to many in their new designs). IMO and IME, Jim Bergantino is quite the genius at this.

 

[Arjank]

cab based on what it looks like on the scope, since that is typically a very artificial environment that will literally never be recreated in a live situation with an EB and amp.

If a cab allready behaves "badly" on a "scope" it will most likely behave worse in a room.

Like I mentioned earlier, "flat" doesn't necessarily mean "true". There are way more (measurable) parameters that can visually show how a speaker behaves.

I rather have one component of the chain to be "true" or "flat" or whatever you like to call it and use the other components to shape the sound. You'll likely have more chance to create a good sound in all the different environments you're going to play. Having a cab that colors the sound introduces another unpredictable component.

 

[lyla1953]

Got news for you...once you amplify an instrument, "true" goes out the window.

+1

 

[1958Bassman]

You will never get a "true" sound, yes, but you can get it to be transparent enough.



Piezo?

Those aren't necessarily going to be absolutely faithful to the resonances, either. Variations exist in everything- the only way to find out if the amp/speaker/effects chain are able to give the "true" sound is through measuring the instrument's resonances and the electrical output, then comparing that with the acoustical output from the speaker(s). The chance of the acoustic output being exactly the same is nil, partially due to everything in the signal path and because of the room's acoustics. If this is compared in an anechoic room, great, but the rig will never be played in that kind of acoustical space. This (anechoic) is almost impossible to achieve for low frequencies and the rule of thumb I have heard is that extending the anechoic range by 10Hz costs about $1M. Many tests are now being done outside, at ground level, in a place where no (or few) reflections are likely.

 

[Arjank]

When you roll in the concept of 'midrange character/distortion' levels, things get even more crazy,

Been there done that.

Back in the days when I had my primus coverband(like 15years ago) I used two cabs with each a 15" and a 6.5" guitar mid (sorta 15/6). This really gave me that raunchy mid where les Claypool is famous for, the thing is, I couldn't really use that rig other then for those raunchy rock tones.... When I started playing more fusion/jazz/funk I needed a more flexible rig.
When I want to get that raunchy mid with my current rig/cab I really need crank the tube pre-amp to get some of that grid I used to get from those "crappy" 6.5" drivers

 

[KJung]

If a cab allready behaves "badly" on a "scope" it will most likely behave worse in a room.

Like I mentioned earlier, "flat" doesn't necessarily mean "true". There are way more (measurable) parameters that can visually show how a speaker behaves.

I rather have one component of the chain to be "true" or "flat" or whatever you like to call it and use the other components to shape the sound. You'll likely have more chance to create a good sound in all the different environments you're going to play. Having a cab that colors the sound introduces another unpredictable component.

Again, what is 'performing badly'. For electric bass amplification (and typically a DB with pickup), 'flat' is just another arbitrary EQ curve. Unless you are measuring the cab on the scope using the amplifier that the customer will be using, and quite frankly, the bass the customer will be using, that tells you very little about how it will sound.

Put another way, 'flat' on the scope is just as 'colored' as a bit of lower mid range bump, and a slight rise in the upper midrange, etc., etc.

And, that midrange character, top of the driver response, etc., etc. is key, and mostly overlooked. It is why IMO some very good PA cabs sound simply awful for bass guitar amplification with many basses and all in one heads.

+1 in general to your comments, just pointing out from my experience, gigging virtually every cab that is marketing as 'transparent and flat' for years (EA, Acme, fEARful, etc.) that all cabs have their quirks and will sound surprisingly good or bad once the entire signal chain is taken into consideration.

Also, and possibly even more importantly, the context in which the player typically performs must be taken into account (for example, a dub situation where the KEY is massive mid bass response at high volumes with no compression or break-up, or an aggressive rock setting, where tight, round low end and the break-up characteristics and upper mid response of the cab is key, to a more 'smooth jazz' situation, where that 'tweeter floating above the cab' tone with a nice dip in upper midrange, combined with a deep bass response is key etc., etc.).

 

[1958Bassman]

Depends on the Qts of the system. The relatively low Qts of .50 required for a 6 dB/octave rolloff is probably rare in a bass cab. I would guess that most sealed bass cabs have a Qts of greater than .707, and therefore a rolloff rate of greater than 12 dB per octave.

Right, but the Qts isn't going to be as high as a typical vented cabinet that was "designed" (or, the builder made it to be a particular size and just accepted the end results) to hit hard. rather than faithful reproduction. I wasn't considering a cabinet with internal volume that's so small that its Qts is so high. The loss of low frequency response and narrow peak would make it unusable, IMO.

I have never seen a speaker in sealed enclosure with Qts of .707 and roll-off approaching 12dB/octave. If the Qts is in the 1.0+ range, it couldn't be called 'accurate' and isn't Qts= .707 where the roll-off is 6dB/octave, anyway?

 

[Arjank]

isn't Qts= .707 where the roll-off is 6dB/octave, anyway?

The only systems that have an acoustic roll-off of 6dB are open-baffle cabinets. Drawback is that you need a very WIDE baffle to get the cut-off frequency reasonably low.

 

[1958Bassman]

There are a lot of loudspeaker systems for hifi that are far from flat but do sound very realistic and true. A flat response is just one (but important) parameter of how a speaker system sounds.

Since most rooms aren't acoustically treated to eliminate/minimize standing waves, it will be all but impossible to achieve flat/smooth response. When a rectangular or square room is the venue, sound quality goes out the window and it's time to limit the A) SPL and B) bass response because of the hot/dead spots caused by comb filtering. If more venues had some kind of bass traps, this topic wouldn't be the problem it is. I'll take smooth and controllable over flat, any day.

[/QUOTE]I think a lot of people are in shock how "acoustic" their bass guitar sounds when played through a very well designed loudspeaker system.[/QUOTE]

I think most people are trying to use cabinets that can't do what they want, but don't know how to define what they want, know what to expect when placing the cabinet (hard to do, since venues aren't all the same) and often play too loud for the venue.

 

[1958Bassman]

The only systems that have an acoustic roll-off of 6dB are open-baffle cabinets. Drawback is that you need a very WIDE baffle to get the cut-off frequency reasonably low.

So, why not make a sealed cabinet with wings that can be opened, to increase the baffle area, but folded (and fastened) to the sides to allow for easier transportation?

 

[Arjank]

So, why not make a sealed cabinet with wings that can be opened, to increase the baffle area, but folded (and fastened) to the sides to allow for easier transportation?

What you do then is lower the baffle-step which works actually pretty much the same as the cut-off frequency of an open-baffle system.
You would need very large wings to get the baflle-step down to e.g. 70hz.

 

[Arjank]

Since most rooms aren't acoustically treated to eliminate/minimize standing waves, it will be all but impossible to achieve flat/smooth response. When a rectangular or square room is the venue, sound quality goes out the window and it's time to limit the A) SPL and B) bass response because of the hot/dead spots caused by comb filtering. If more venues had some kind of bass traps, this topic wouldn't be the problem it is. I'll take smooth and controllable over flat, any day.

If you talk about real bass-reproduction then a "true" or "real" sounding basscabinet isn't necessary. A bassguitar's characteristic sound mainly comes form all the upper harmonics. If you rob he signal it's harmonic content and only reproduce the strings resonant frequency and 2nd harmonic you will not be able to distinguish a jazz bass from a precision.

Standing waves, room modes etc. are (IMO)a different topic and isn't something that has to do with true or real sounding.

 

[bgavin]

Right, but the Qts isn't going to be as high as a typical vented cabinet that was "designed" (or, the builder made it to be a particular size and just accepted the end results) to hit hard. rather than faithful reproduction. I wasn't considering a cabinet with internal volume that's so small that its Qts is so high. The loss of low frequency response and narrow peak would make it unusable, IMO.

I have never seen a speaker in sealed enclosure with Qts of .707 and roll-off approaching 12dB/octave. If the Qts is in the 1.0+ range, it couldn't be called 'accurate' and isn't Qts= .707 where the roll-off is 6dB/octave, anyway?

You are thinking "Qtc" which is the cabinet parameter.
"Qts" is the driver parameter.

 

[DukeLeJeune]

You are thinking "Qtc" which is the cabinet parameter.
"Qts" is the driver parameter.

My bad, I'm the one who first typed Qts when I meant Qtc. Thanks for catching that.

I have never seen a speaker in sealed enclosure with Qts of .707 and roll-off approaching 12dB/octave. If the Qts is in the 1.0+ range, it couldn't be called 'accurate' and isn't Qts= .707 where the roll-off is 6dB/octave, anyway?

A sealed box with a maximally flat (Butterworth) alignment of Qtc = .707 rolls off at 12 dB per octave. There's a widely used instructional car audio site that says 6 dB per octave, which is apparently a typo, but unfortunately people are being misinformed by that. The accompanying graph on that page on the car audio site is correct, here's the link, scroll down and look at the entry under "Qtc":

http://www.bcae1.com/spboxad2.htm

EDIT: I wrote to the owner of that site about the typo, and he corrected it, so I guess he agreed with me.

Actually I was wrong when I replied to you earlier saying that a Qtc of .50 gave a 6 dB per octave rolloff. That is only true of the initial rolloff rate; all sealed box rolloffs converge towards 12 dB/octave, though different Qtc values result in different behavior in the two octaves or so around system resonance.

 

[eukatheude]

Why should you want the "acoustic" sound you hear when you pluck your bass unamplified?

Why not?

Those aren't necessarily going to be absolutely faithful to the resonances, either. Variations exist in everything- the only way to find out if the amp/speaker/effects chain are able to give the "true" sound is through measuring the instrument's resonances and the electrical output, then comparing that with the acoustical output from the speaker(s). The chance of the acoustic output being exactly the same is nil, partially due to everything in the signal path and because of the room's acoustics. If this is compared in an anechoic room, great, but the rig will never be played in that kind of acoustical space. This (anechoic) is almost impossible to achieve for low frequencies and the rule of thumb I have heard is that extending the anechoic range by 10Hz costs about $1M. Many tests are now being done outside, at ground level, in a place where no (or few) reflections are likely.

We are saying the same thing. You can't get it to be dead on the same sound, but you can get close enough.

 

[bgavin]

My bad, I'm the one who first typed Qts when I meant Qtc. Thanks for catching that.

No worries.
Not intended as a "gotcha", just a catch for correction.

 

[will33]

@ Arjank & DukeLeJeune -

Conversations like yours are one thing that make this place great.

If one wants to, they can read a bit of back and forth like that and use it to go searching and reading and learning for a very long time.

The bit about coaxial coincedence and motor structure will fulfill my requirement of learning something new everyday for quite a while.

 

[JimmyM]

I'm under the impression that most bass cabs have a deliberate native "voicing" that is intended to sound good on electric bass, and relatively few are designed to be essentially neutral. My background being in other areas, it wasn't until fairly recently that I even got a decent idea of where the goal posts are for a deliberately "voiced" bass cab. I think that end of the market is a lot bigger than the "neutral" end of the market, as ime people seeking DI-like sound out of their bass cabs are the exception rather than the rule.

I think that's absolutely true. I also believe that a lot of folks who believe they want "neutral" voicing really don't, and I believe a lot of folks who claim to want it wouldn't know it if it bit them in the face Learned that lesson the hard way my own self.

Thanks for the mention, will33. Just to clarify a bit, this isn't just theoretical - I have customers who have replaced their studio monitors with my bass cabs, and customers using them for high-end home audio. My bass cabs have been specified as tracking monitors for professional recording studios by the acoustician who designed those studios (and he's using a pair in his living room). So it's not just theoretical - my bass cabs are actually being used this way by serious professionals.

Duke, I'm telling you...if you marketed some of your designs as PA and studio cabs, they would sell.