Low Down Sound 15/6.5 Cab

[greenboy]

I was just thinking how odd it would be if good Sound Reinforcement designers didn't pursue "flat" as an ideal. Or designers of studio monitors, or those designing for the home audio enthusiasts (Duke LeJeune really thinks and does some great stuff there).

Would there be progress? Would there be any way for engineers to translate a good mix from one environment to another and give others to at least sense some of what he/she did? How would one be able to solve local environmental acoustics problems? How could they if they had no idea what was contributed by environment, and what was contributed by the reinforcement system?

And how would audiences in homes and venues really feel about the recording and playback process if it was even more haphazard and besieged by variables than it is now?

"FLAT" as a construct had to be invented. And then pursued. And will continue to be for at least part of the signal chain, in each link of the recording and performance experience.

 

[KJung]

I was just thinking how odd it would be if good Sound Reinforcement designers didn't pursue "flat" as an ideal. Or designers of studio monitors, or those designing for the home audio enthusiasts (Duke LeJeune really thinks and does some great stuff there).

Would there be progress? Would there be any way for engineers to translate a good mix from one environment to another and give others to at least sense some of what he/she did? How would one be able to solve local environmental acoustics problems? How could they if they had no idea what was contributed by environment, and what was contributed by the reinforcement system?

And how would audiences in homes and venues really feel about the recording and playback process if it was even more haphazard and besieged by variables than it is now?

"FLAT" as a construct had to be invented.

Again, as I've posted many times, this is key for systems designed for programmed music, front of house systems, etc. So, +1 all the way.

What makes me wince is when some describe this approach as some sort of 'gold standard' for bass guitar backline amplification. IMO, that is a TOTALLY different thing, and is why many top touring acts still use a mic in front of a very 'voiced' bass rig that then is reproduced at volume through a more neutral front of house system.

Again, I'm ONLY discussing bass amplification backline, which for many, is an integral part of 'their sound'.

 

[greenboy]

What makes me wince is when some describe this approach as some sort of 'gold standard' for bass guitar backline amplification. IMO, that is a TOTALLY different thing, and is why many top touring acts still use a mic in front of a very 'voiced' bass rig that then is reproduced at volume through a more neutral front of house system.

Yep, and a good engineer (or sometimes a bassist choosing his own mic) will not necessaily choose the flattest mic or micing technique either - but will all the while be aware of its coloration as referenced to "flatness". In my experience anyway. Why? Because it means that one can make informed desicions when micing a similar or dissimilar rig later on, or to meet a mix vibe the band might have gotten on their promo CD, etc.

If nothing else, "flat" is a reference tool.

For myself, I like rigs that are relatively flat, not so much for the on-axis but for the off-axis. I've found it aids me and the people I play with on the often relatively small stages with limited monitors, to get stage mixes that keep everybody working well together by hearing well together. And I like the fact that I can DI the exact same signal that's going through my cab to the PA, no surprises, no big tonal discrepancies since my stage enclosure sounds pretty much like a good PA stack.

I like the fact that I seem to be less prone to "room effect" obstacles than before, don't seem to have to do much at all to translate decently from one environment to the next. And comparing notes with Duke LeJeune, I think that's a benefit he has been after too, with his home products, and hopefully soon, his bass cabs.

 

[DukeLeJeune]

Since my name came up in this context (thanks, greenboy!), let me toss out a couple of comments on room effects.

One of the reasons an unamplified acoustic instrument (acoustic guitar, piano, human voice) isn't particulary susceptible to "room effects" is that the spectral balance it puts out is relatively consistent across a broad arc. As a result, whether the room contributes a lot or a little reverberant energy doesn't really matter - that reverberant energy will have essentially the same spectral balance as the first-arrival sound, so it doesn't skew the perceived tonal balance. This is a slight oversimplification, but the principle is valid.

The closer a bass cab comes to mimicing this characteristic of many unamplified acoustic instruments, the less susceptible it will be to room effects.

When I look at a loudspeaker design, one of the first things I try to figure out is the radiation pattern. Now your initial reaction is probably, geeze who cares - I mean, how obscure can you get??

Well, do you care about how the cab sounds? Of course you do.

Okay then, why does a cab sound the way it does? The tonal balance is the main thing.

What creates the tonal balance? Ah - here we go! In a room, the ear derives tonal balance from a combination of direct and reverberant energy. The farther back the listener, the greater the relative contribution to tone that the reverberant energy makes.

So when it looks like the geeks among us are focusing on trivia and esoterica when we go off about dispersion, we're really talking about tone. Even outdoors where there is no reverberant component, if the upper frequencies have a broad, relatively uniform horizontal coverage pattern, the tone will be better for listeners who are not along the centerline of your cab. Audience members across a broad arc will be able to hear the notes the way you meant them to be heard in the mix because the overtones will be present.

Well that's my story anyway.

 

[lbwdog]

Bravo, KJ & GB!! Great discussion by two of the more articulate posters on this forum!!

This thread has a particular interest for me as I am truly looking for a standalone cab that will satisfy me for the rest of my playing days. My days of full time gigging are behind me (I guess), but the quest for a rig that will perform to my tonal and portability goals hasn't quite been fulfilled.

Ken's review of this cab caught my attention as I have been a proponent of the concept of using two or three dedicated drivers in an optimized cabinet since following greenboy's "Boutique Three-way" thread back in 2007. I followed that thread and became one of the early adapters to the LS 1503, even retrofitting the stock woofer with the 3015LF, then, poof...., crossover problems forced me back to using my heavy 4x10 cab. As a studio veteran, I always thought that a cab that could reproduce like a great monitor was right up my alley, knowing that my tonal goals and other desired sound characteristics could be performed upstream with EQ, overdrive, effects, etc.

What I would really love to see is Ken's (and other's) review of an LDS built, fEarful design of this cab. While using mostly the same components, it has a different form factor ( basically taller) and a crossover that seems to come from a different school of thought. Yes there was much ado about my choice of expression in another thread regarding the "true crossover". While I am just an old bass player and not an acoustic engineer, I follow the theory that each one of these drivers are probably "Best In Class", and should be utilized in their optimum (IMHO) range, so I'd like to know how they perform in the fEarful environment. Who knows...I might prefer the 1.3 KHz point of the Patterson crossover, but I'm thinking I would prefer my midrange driver being brought in an octave or so lower.

So Ken, if you have a chance to audition an LDS built fEarful 15+6, I would certainly be interested in hearing your take on the differences. If anyone could hear (and describe) them, it would be you!

 

[Maurice Carr]

Then you sir, are Really, Seriously Olde; cause I've met Ken, and he ain't No Young-ster.

...and I've met Bill, and I assure you he's older than me, and I'm no youngster either!

 

[KJung]

So Ken, if you have a chance to audition an LDS built fEarful 15+6, I would certainly be interested in hearing your take on the differences. If anyone could hear (and describe) them, it would be you!

This is definitely in the plan, and I really look forward to checking out Greenboy's design as executed by Don and Ralf. My two 410's, both relatively similar in size, both with Eminence Neo drivers, both with similar tweeters, sound totally, completely different due to, I assume, the crossover design, tuning, and a bit of difference in the internal volume of the cabs. So, I realize that the 15/6.5 I tried and reviewed in this thread was just one execution (and a darn nice one!) of this general configuration.

Stay tuned!

 

[KJung]

Since my name came up in this context (thanks, greenboy!), let me toss out a couple of comments on room effects.

One of the reasons an unamplified acoustic instrument (acoustic guitar, piano, human voice) isn't particulary susceptible to "room effects" is that the spectral balance it puts out is relatively consistent across a broad arc. As a result, whether the room contributes a lot or a little reverberant energy doesn't really matter - that reverberant energy will have essentially the same spectral balance as the first-arrival sound, so it doesn't skew the perceived tonal balance. This is a slight oversimplification, but the principle is valid.

The closer a bass cab comes to mimicing this characteristic of many unamplified acoustic instruments, the less susceptible it will be to room effects.

When I look at a loudspeaker design, one of the first things I try to figure out is the radiation pattern. Now your initial reaction is probably, geeze who cares - I mean, how obscure can you get??

Well, do you care about how the cab sounds? Of course you do.

Okay then, why does a cab sound the way it does? The tonal balance is the main thing.

What creates the tonal balance? Ah - here we go! In a room, the ear derives tonal balance from a combination of direct and reverberant energy. The farther back the listener, the greater the relative contribution to tone that the reverberant energy makes.

So when it looks like the geeks among us are focusing on trivia and esoterica when we go off about dispersion, we're really talking about tone. Even outdoors where there is no reverberant component, if the upper frequencies have a broad, relatively uniform horizontal coverage pattern, the tone will be better for listeners who are not along the centerline of your cab. Audience members across a broad arc will be able to hear the notes the way you meant them to be heard in the mix because the overtones will be present.

Well that's my story anyway.

I again truly wish I and my audience could hear meaningful differences across many acoustic situations between my vertical 212's, the vertical 2 x 210 stack I used for a while, and my 'poorly designed' 410's (based on my 'on stage experience', other players sitting in on my rig, and hearing similarly configured rigs in various venues as a member of the audience). However, unfortunately, I believe boundary effects, general room acoustics, etc. are much more complicated in a live music situation (especially when talking about slotting a bass guitar into a mix using only backline with no front of house support) in generally horribly designed (from an acoustical standpoint) venues versus the impact of the design components you talk about in a more controlled environment (i.e., a music listening room) with programmed music at 'normal volumes'.

I of course could be wrong, but again, in the zillions of times I've stood out in the audience listening to many different bass backline designs with no front of house support, some of the most even, constant, articulate, punchy tones I've heard in various positions in the room (front, side, back, front) have been from bass rigs using cabinets that would make an acoustic engineer wince in pain from a design standpoint.

I again feeel that the amplification of the electric bass is relatively unique versus the 'programmed music audio' application.

IMO, and of course, from a user/musician perspective only, since I have zero technical background on speaker design. I still recommend the cab purchaser use his/her ears and, most importantly, if possible, try a cab with their own bass and amp. That mix and match can result in a yin yang that can easily result in a 'more flat voiced cab' sounding 'less flat', and a 'more voiced cab' actually moving toward a more even tone, given how the inherent peaks and valleys in the preamp voicing, cab, and especially the instrument, line up. IMO and IME!

 

[burk48237]

KJung I of course could be wrong, but again, in the zillions of times I've stood out in the audience listening to many different bass backline designs with no front of house support, some of the most even, constant, articulate, punchy tones I've heard in various positions in the room (front, side, back, front) have been from bass rigs using cabinets that would make an acoustic engineer wince in pain from a design standpoint.

One other point that is often not considered when looking at bass backline. It's a bass GUITAR, not a bass frequency providing stimulation unit (I should patent that one). And how many electric GUITAR players do you know that look for flat rigs? I wonder what a slightly overdriven Fender Princeton, Vox AC30 or cranked Marshall half stack would look like in a Frequency response test? Not flat I can assure you. Why is it that most guitar players aren't looking for an amplification system that produces the most even, realistic reproduction of the natural sound of a Fender Telecaster? Why is it that they hate the sound of an unamplified solid body run into the finest studio board direct? Probably the same reason most bass players like to stick a U5 or a Reddi in signal chain in the studio, and many like to mike a B-15.

Well I play bass GUITAR in similar situations Rock, R & B, and Blues. And my amp (like the guitar players) is part of my tone. It's the same reason that the Ampeg SVT is most requested backline in the business. I have found similar to Ken that a certain tones work in certain settings, and I try to get those tones. They may not be "flat", but they support the band, while cutting thru a dense mix.

I can't tell you how may times I've sat in an audience at a club where some player had thousands of dollars worth of "even, flat" sound reproduction equipment and he got lost in the mix somewhere between the Mesa Bogie and the kick drum. His tone may have sounded great soloed, but live he was trying to compete with the kick drum and the low end of the guitar rig. And in most cases bass players lose when the do this. The key is to pick the slot between the Bass drum and the guitar rig and amplify the H@$$ out of it. The sound guy (if you even have PA support) isn't going to help you, he's tiered from the hour he spent on the tom toms during the sound check.

This is the theory behind Schroder cabs (which go a bit too extreme IMO). Punch the heck out of the low mids and surprise, you can hear the bass player. Why? Because, instead of trying to amplify your "pure full sound" your placing yourself in the most open slot in the mix between the Bass drum and the guitar rig. Instead of competing with the kick your complementing it.

A great example of this is what happens when you do the opposite. Try a Eden 800 with a 410 and crank the Enhance full blast, boost the bass and treble knob just a bit, now you have zero low mids, it sounds great soloed. Now join the band and watch your 800 watts have trouble competing with a 20 watt Princeton Reverb. It's really not rocket science.

 

[Chef]

It is too Rocket Science...

Alan Loshbaugh;
Rocket Scientist

 

[burk48237]

It is too Rocket Science...

Alan Loshbaugh;
Rocket Scientist

I don't know, I tend to think of you more as a "bass frequency providing stimulation unit facilitator"

 

[greenboy]

It is too Rocket Science...

It must be. Because Burk's "Eden 800 Enhance turned up full blast" example is about as far as you get from "flat", with its super-exaggerated bass and treble boosting and ultra scooped mids ; }

And I doubt his anecdote of "some player had thousands of dollars worth of 'even, flat' sound reproduction equipment" has anything to do with we are talking about (I've seen that guy too and he's often a real pain to mix), since that anecdotal guy usually has very odd ideas about what flat is and how to pursue it. Missapplied knowledge bassed on wallet frenzy and knowing just enough to be dangerous. It certainly bears no resemblance to the possible voicings 15/6 configs are likely to possess.

As for "mix slotting" between kick and other content, the electric bass already is well-slotted as it does not usually have especially strong fundamental energy on the lower strings down by the nut, putting most of its energy at the octave and octave and a fifth overtones, well above the body of the kick and below the guitar-and-amp voicing.

A lot of red herrings here that have nothing to do with anything I've said, or Duke LeJeune either.

 

[KJung]

As for "mix slotting" between kick and other content, the electric bass already is well-slotted as it does not usually have especially strong fundamental energy on the lower strings down by the nut, putting most of its energy at the octave and octave and a fifth overtones, well above the body of the kick and below the guitar-and-amp voicing.

Depends on the bass, the player's techniqe (i.e., his right hand plucking location and the strength of his plucking or slapping which can massively change the low end profile of the instrument), how the bass drum is tuned and the size of the bass drum, the mix and type of music, the soundman's EQing of the bass drum and bass if there is front of house support (many times, on the gigs I play, the bass drum is mic'd, the bass guitar is not), the EQ choices of the bassist, the low end profile of the stage rig, etc., etc., etc., etc.

I agree that Burk's comments have more to do with a 'scooped' tone profile than what we are talking about.

 

[greenboy]

I again feeel that the amplification of the electric bass is relatively unique versus the 'programmed music audio' application.

The most chaotic environments tend to be really large venues - huge indoor arenas - and that's where a lot of the advancements in dispersion control have been fought for. And the knowledge gained then trickles down into club PA and ways to hear better onstage. It's not about "programmed music audio".

Anything goes in bass reinforcement. There's a history of working with stuff that was as good as they knew how to do it in the old days, and to make it work for an audience the approaches of using DI and enclosure micing were quickly established. But carrying the house continues to be a reality for many of us, and by evidence of the posts on talkbass the problems of room boom, bass buildup, uneven coverage of the bass's midrange frequencies, stage mix versus what the room is getting... continue to plague us.

 

[KJung]

The most chaotic environments tend to be really large venues - huge indoor arenas - and that's where a lot of the advancements in dispersion control have been fought for. And the knowledge gained then trickles down into club PA and ways to hear better onstage. It's not about "programmed music audio".

+1 I was using 'programmed music' as a proxy for the goal of 'accurate reproduction of a full range source', whether that be a CD or a complex feed from a live band that is then sent through massive signal processing (compression, EQ, etc.) in order to get the band to sound as close to 'programmed music' as possible in the venue.

 

[greenboy]

Depends on the bass, the player's techniqe (i.e., his right hand plucking location and the strength of his plucking or slapping which can massively change the low end profile of the instrument), how the bass drum is tuned and the size of the bass drum, the mix and type of music, the soundman's EQing of the bass drum and bass if there is front of house support (many times, on the gigs I play, the bass drum is mic'd, the bass guitar is not), the EQ choices of the bassist, the low end profile of the stage rig, etc., etc., etc., etc.

Sure, a lot of bassists use excessive EQ in attempt to get a fundamental loud (and end up boosting the midbass instead). But because string physics and scale length, wood resonances, magnetic pickup and pickup placement realities (and lastly, enclosure/woofer practicalities), the fundamental still ends up being a lesser component of the sound, until you get into longer scale EUBs.

I can't do anything about people who don't know how to tune or mic a kick drum ; }

 

[burk48237]

My example about the scooped tone was a extreme example of the opposite of a low mid punch sound. I did not call it flat. My point was those frequencies (which are part of a flat sound) get lost real easily when that's all you reproduce. The Fundamental of a low B string is what? 32 Hz (it's been a while). Well if your rig is producing 32 hz flat, at the same level that it's producing 100 hz, then your using an awful lot of power to reproduce frequencies that are getting drowned out by the bass drum. Wouldn't it be better to roll off (not flat) all frequencies below about 60-80 and concentrate your power on producing those frequencies where we agree the bass is naturally slotted?

My big point is that flat (even) response wastes a lot of power producing sounds that get lost in the mix anyway. It takes a lot of wattage to reproduce low bass accurately. So instead of trying to be sure your reproducing 20-20,000 flat, why not try to reproduce the slot where your instrument naturally falls efficiently?

Greenboy, while the bass may be naturally slotted in the low mid area, a lot of players are trying to get an even response across a much wider spectrum. And in many cases (lousy rooms) they're getting lost in the process.

Now does this mean flat should be abandoned? There are plenty of situations where flat, even sounding set ups work. In low volume intimate settings, jazz trio's, certain all acoustic acts. Anthony Jackson sounds great in a jazz club or a hall with great acoustics. But I suspect if I went for Anthony's tone in a band with a loud drummer, lousy club, and a Marshall stack I'd lose. The issue is not flat is the starting point, but what tone works in the your setting.

Ironically the 15/6 Don built works better for me then Ken, I'm looking for a more old school sound. Ken's (being the mean mofo slapper he is) is thinking Marcus. He needs a tweeter, it's all cool. I do look forward to hearing the different takes on these cabs.

 

[KJung]

Sure, a lot of bassists use excessive EQ in attempt to get a fundamental loud (and end up boosting the midbass instead). But because string physics and scale length, wood resonances, magnetic pickup and pickup placement realities (and lastly, enclosure/woofer practicalities), the fundamental still ends up being a lesser component of the sound, until you get into longer scale EUBs.

I can't do anything about people who don't know how to tune or mic a kick drum ; }

Again, +1.

 

[greenboy]

My point was those frequencies (which are part of a flat sound) get lost real easily when that's all you reproduce. The Fundamental of a low B string is what? 32 Hz (it's been a while). Well if your rig is producing 32 hz flat, at the same level that it's producing 100 hz, then your using an awful lot of power to reproduce frequencies that are getting drowned out by the bass drum. Wouldn't it be better to roll off (not flat) all frequencies below about 60-80 and concentrate your power on producing those frequencies where we agree the bass is naturally slotted?

I agree entirely, Burk. I make no attempt to tune a cab lower or go for more internal space in an enclosure than it takes to reproduce a low B or a drop-A string at its predominant energy focal point with authority. Not only does it waste power, but if it's on a stage anywhere near PA subwoofers it's just more likely to cause cancellations and resonances. Its counterproductive to go after the lowest fundamentals.

Also as a soundman, and as a listener at other people's gigs, I hear a lot of guys that are boosting low end like crazy and never really getting coherence down there. They are fighting themselves, their enclosures, and usually the room. Tough to deal with as a sound engineer, and not so pleasing as a listener.

So where "flat" concerns me most is from the octave harmonic and above and up through the midrange and into the lower treble - or higher treble too if a tweeter is also included. This is where the most "character" of any bass guitar or player is found. It's also where the dispersion stuff I've talked about is beneficial.

EDIT: Just to clarify, if a savvy buyer is looking for a near field studio monitor, they are looking for one that is relatively flat, but not down to 30 Hz or whatever. They are looking for desirable flatness starting somewhere above that. That's what I've actually been alluding to - something that is relatively flat within its passband, but not necessaily across the entire range of human hearing. And they may be looking for a wider sweet spot to listen in, which is part of what the equal power response and off-axis response talk has been about.

 

[rpsands]

Another thing to keep in mind is that rolling off below 60-80 is one thing - rolling off below 100 is another. Lots of cabs out there roll off steeply before even the octave overtone of a low B. Schroeder's a good example - my 21012 is pretty anemic anywhere below low D or so.

If you want lots of sound below 100hz-ish, having a cabinet that is flat there is going to gain you extra power for free basically. Say your cabinet is essentially -10db @ 60hz - so a high powered cabinet would be 91db instead of 101db at that point, meaning if you want lots of 60hz you're going to need to boost the lows and suck more energy out of your amp.

Lots of folk just don't want a bassy sound, but it costs you absolutely nothing to roll off the bass with a fEarful/15/6 style cabinet. You aren't "wasting power" producing low frequencies because the speaker has the capability of doing it.