woofer sizes?

[ofajen]

And here's some beginning reading on the subject:

http://www.bobhodas.com/pub1.html

Oh, yeah, another thing is that most studio control rooms are a comb filter disaster with monitors beaming out just over consoles, keyboards, racks and what not. I had to move my stuff (which ain't much these days, thanks to the wonders of a digital age) to the opposite side of the monitor location to get the CPU out of the studio, but the silver lining is that there is just empty space between my listening chair and the big monitors set up in a midfield configuration, so things sound as good as they ever have here. BTW, I'm no more enthusiastic about close monitoring than the author linked above, perhaps less so.

Now, if I had an extra $6K or so, I'd be checking out the ASC Attack Wall. That seems to be a pretty much foolproof way to get a killer midfield monitoring situation in any room that is portable and translates well. The problem with room acoustics is what led people to use close monitoring to begin with, but the cure may be worse than the disease. Better to fix the acoustics and stick with good full-range monitors if possible. And when you're just tracking you could probably stand to use some of the Studio Traps around the mike or around the tracking room to improve the sound, so they could do double duty.

Otto

 

[barefoot]

Move the stick more: This was the principle of the acoustic suspension speakers; make the speaker move longer distances to push more air. Unfortunately, it required a lot heavier cone and a long voice coil which dropped the efficiency way down and made the system sluggish as hell....

We add all of this knowledge to our first basic axiom ("Everything is a trade off.") and we can now discuss our choices, the tradeoffs, and make some more intelligent decisions about how to choose a speaker system.

Harvey,

I agree with your list of tradeoffs, and we certainly cannot invent new physics. However, technological developments can make some parameter spaces more accessible. Unlike older acoustic suspension designs that use heavy cones, loose suspensions, and weak motors to achieve low frequency extension, I take the opposite approach. I use very stiff light cones and high BL motors in very small sealed enclosures. The stiff acoustic suspension provides excellent excursion control. This creates a very low Q bass roll off with a rather high corner frequency. The low frequency alignment, rather than being setup electromechanically, is actually done electronically using a transformation filter. The net result is an extremely fast, low distortion and well controlled bass response. Not to mention, I can build those small boxes much more rigidly than big boxes.

Now, this approach has only become practical in the past few years due to its one very significant tradeoff, namely POWER. My designs produce very low well damped output though shear brute force. They require powerful amplifiers. The latest generation of extremely high performance switching amplifiers fills this need. Likewise, with all this power I need speaker drivers that can handle it. And it so happens that there is also a new generation of driver technology that yields very long excursions, high linearity and low power compression.

I know you're not suggesting otherwise, but I want make it clear to everyone: There are sometimes new and better ways to skin the old cat.

Thomas

 

[CoolCat]

yeah, I have an old MIX magazine, Hodas says he likes the subs, and also didn't agree the bass is fully non-directional. His "reality" check was telling the reader top set their sub in a corner and if they can't tell which corner its in he'd been surprised. If I recall he actually was mentioning 2qty subs in his opinion.

we can't invent new physics...thats funny, I think Marketing guys can?


Materials are always changing. I'm at a college in R&D and there's a mountain of new materials and sciences under work. The nano-tubes is a big one!
Stronger than steel and lighter than paper, in lamen terms.
its already here, in most al the colleges around the world, but no one can mass produce it.

Never thought of it for speakers? light and strong, nano-tubes.

 

[Harvey Gerst]

As I've pointed out, you can't change physics, and the tradeoffs are always there. Thomas at Barefoot took the "Move the stick further" principle into the present day with new cone/motor assemblies but as he says, it takes a ton of power (and it ain't cheap). His smallest system is around $6,500; not exactly the kinda change you're gonna find under the cushions of your couch.

None of the stuff I've mentioned so far is a bad way to go, and each can be optimized to produce very good sound, but it's usually at a tremendous cost.

To paraphrase an old saying*:

Small size. Flat response. Cheap price. Pick any two.

What you didn't pick is what you give up to get the other two.

You want small size and flat response? It won't be cheap price.

You want small size and cheap price? It won't be flat response.

You want cheap price and flat response? It won't be small size.

All of the examples and techniques I've discussed so far are just generalities. I'm purposely avoiding discussing all the science that's involved - wait till we get to crossovers for some interesting new facts - for some of you, anyway.

The problem is still the same for every speaker manufacturer: how to get the sound reasonably "flat" (and that's like Clinton defining what "is" is), and then, how to deliver that sound to the listener. And, of course, at what price point.

As I said, more to come...



*NOTE:

The original saying (popular in engineering departments) was:

Cheap, fast, good**. Pick any two.

What you didn't pick is what it won't be.


**Some engineers substituted "reliable" for "good".

 

[mshilarious]

You want small size and cheap price? It won't be flat response.

You want cheap price and flat response? It won't be small size.

Yeah, I started with the first one (second on your list), then decided I could fix the response with a sub . . . now I'm moving to the second. To be fair to me , my studio in my old house couldn't accomodate anything else, it was so tiny.

The nice thing about big is it seems easier to design. If you have the space, that seems the way to go, from my point of view. But maybe ask me again after I'm done.

I'll be a happy man when these bad boys that I'm building are dropped in the walls . . . that I still need to build

My old 6.5s are gonna get rebuilt as an MTM for center channel. Not that I've ever done a surround mix . . . build it and they will come!

 

[bilco]

Great thread; thanks Harvey!!

bilco

 

[stevetat]

Harvey, just wondering if you think that psycho-acoustic bass enhancement systems like Waves MaxxBass or Aphex Big Bottom have a place in the control room or if they're better left to improving lower-end consumer and pro stuff?

 

[xstatic]

In general, I would say that those enhancers are better left out completely. However, I have had success with them is some applications. Mostly as a channel insert for certain things, or have heard them used very well in guitar and bass rigs. I would NEVER put one in line with my main feed to my monitors though, or even a PA for that matter (well maybe if ALL I was doing was racks and stacks for a DJ, but probably not even then).

 

[andydeedpoll]

ok, a completely different question now but still monitor related.

how important is the amp? does it just do what it says on the tin, or can it have a really dramatic effect on the sound of the monitors? i only ask because i've already got an amp that i use for my current speakers, and would love to get some "pretty good" passives and use the amp i've already got than have to get some "less good" actives.

any thoughts?

Andy.

 

[ofajen]

Harvey, just wondering if you think that psycho-acoustic bass enhancement systems like Waves MaxxBass or Aphex Big Bottom have a place in the control room or if they're better left to improving lower-end consumer and pro stuff?

In my worldview, they're crap and best left off the mix in all cases. There are better ways to get a better sound and besides, it's hard enough to get a decent monitoring system and listening space that accurately presents the bass without making things harder by messing stuff up irreparably with that kind of gizmo. A mastering engineer can't fully undo the damage you will do, most likely with no idea how it will translate. You can always tinker with that stuff at the mastering stage, where the damage can be undone by remastering.

Otto

 

[CoolCat]

ok, a completely different question now but still monitor related.

how important is the amp? does it just do what it says on the tin, or can it have a really dramatic effect on the sound of the monitors? i only ask because i've already got an amp that i use for my current speakers, and would love to get some "pretty good" passives and use the amp i've already got than have to get some "less good" actives.

any thoughts?

Andy.

Your ears can answer that but, imo, there's a huge difference in sound, up to a certain point.

cheap radio, boombox stereo, average consumer HiFi, Hifi Mid level, Audiophile level... and the "Your out of your mind and obviosuly work for the OIL Cartels!!" level.

 

[Harvey Gerst]

ok, a completely different question now but still monitor related.

how important is the amp? does it just do what it says on the tin, or can it have a really dramatic effect on the sound of the monitors? i only ask because i've already got an amp that i use for my current speakers, and would love to get some "pretty good" passives and use the amp i've already got than have to get some "less good" actives.

any thoughts?

Andy.

Yes, I have a lotta thoughts on amplifiers. Some are better than others, and some interact with the speakers in a good way and some in a bad way. Even though it's possible to build amplifiers with distortions reduced to almost the vanishing points at low levels, higher power levels will sometimes reveal inherent flaws in the amplifier's design.

These flaws can show up as poor frequency response, excessive 3rd and 5th harmonic distortion components (more about THD later), poor damping, restricted power response, sagging power supplies, and severe intermodulation distortion (IM), especially in the transients, due to excessive negative feedback (TIM). All of these design factors can be contributors to poor overall system response.

At relatively low levels, the differences between amplifiers is less apparent.

With the wide range of high powered home receivers available today, most home high-fi amps will do fine, as long as you turn the damn music effects off, and set the tone controls to flat. On some, that's hard to do. I hate those "Concert, Rock, Jazz, Hall, Movie" settings with a passion.