How do find the voicing you want when you don't know what to tweak?

[AllenB]

I'd like a method of balancing timbre 'till I get the sound I'm looking for.

[speaker dave]

Are we talking about designing a passive crossover?

I find in crossover design there are usually a few components that have a nice effect over a broad range. Those are the ones to tweek.

If you were doing a simple two-way, for example, you might find that a series inductor for the woofer, varies response from 800 to 3000, that a resistor on the tweeter effects the treble range in total.

These are just examples, you need to investigate your particular network, either by adjusting some components, or if you are using a computer for optimization, by doing theoretical changes. You will find that certain components have broadband effect and others have more minor effects.

In the end it isn't much different than using a graphic equalizer, but the EQ sliders are defined by component effects or crossover point.

Good Luck,
David S.

[AllenB]

Hi speaker dave, yes I am running passive. I've been trying to work out what parts of the spectrum to cut or boost to change what I am hearing. I've tried the tutorials that tell you what changing each slider will do to the sound.

I'd like something that guides me to know what I want to cut, when I guess what to do I can't always get it right. Something like a tutorial on tuning a brightness and contrast control on a monitor for optimal results.

[speaker dave]

Originally Posted by AllenB

Hi speaker dave, yes I am running passive. I've been trying to work out what parts of the spectrum to cut or boost to change what I am hearing. I've tried the tutorials that tell you what changing each slider will do to the sound.

I'd like something that guides me to know what I want to cut, when I guess what to do I can't always get it right. Something like a tutorial on tuning a brightness and contrast control on a monitor for optimal results.

I see. The tutorials that describe what instruments or sonic effect each octave region has, are a good place to start with but you need to hear the effect yourself.

You can train yourself easily if your computer media player has a graphic EQ built in. I think the Windows Mediaplayers do. Start with a file of pink noise and try each slider up and down, up and down, until you get a sense of what the effect is. With noise you will notice that you can full boost each octave in turn and it sounds like moving up a keyboard, an octave at a time. Once you fix the effect in your mind on noise, try the same on music and human voice. Learn the difference between a single slider boosted and the same slider cut. You should be able to hear a significant difference for octave wide adjusts of 2 to 3 dB.

Someone with a lot of experience can listen to a speaker and guess the frequency of aberation, whether it is up or down and how many dB might be needed to fix it. You don't need to be that good, as long as you can put your finger on what you think is wrong and get there with some EQ trial and error. AB comparisons to a few other speakers of known quality might also help you spot the strongest aberations, assuming they are truly flat!

Hope that helps,

David S.

[speakerdoctor]

I think the key words in Dave's last post are "someone with a lot of experience.....".

The OP wrote "I'd like something that guides me to know what I want to cut..."
What you should use to help solve your problem are frequency response measurements. They can be an invaluable aid during the tweaking process because response curves provide a means to visualize what you are hearing.

[theresa]

Without measurement equipment it is trial-and-error. With passive this can take a very long time along with a lot of money. I use an active crossover, the mini-DSP. So far I haven't setup the measurement equipment but changes are so easy that I haven't felt a great need for it.

[speakerdoctor]

Here's another tool you might consider if you're building a number of different designs and, if you don't want to go the measurement route and rely strictly on your ears. If things work out right, you could voice a speaker before installing the xover in the box. They are sometimes available brand new for <$100 on *bay.

http://www.vidsonix.com/vidsonixnew/boxlit2.pdf

[tinitus]

Originally Posted by AllenB

I'd like a method of balancing timbre 'till I get the sound I'm looking for.

as said, its not so easy
and its not just about adjusting level

phase and "timing" are the key words

voicing ?
probably means something different to different people
personally, Im not even sure I like the word
to me it implies something that isnt really true at all

first step is to have a crossover that makes sense
and you need to understand how the component works
individually, and together
then you have to "know" your speaker, and each individual driver
and how every small change in crossover affects it

different crossover topology appears to relate mostly to speaker design, more than to the choise of drivers

so, we need to know your speakers and crossover, to have any idea about what you are facing

you could start with small adjustments to tweeter
it might affect other xo functions
could be a beneficial sideeffect advantage, or not

[sreten]

Hi,

Basically see the FAQs at : undefinition

also see : FRD Consortium tools guide

Simulation will let you see what you are changing and by what amount.
Done properly it would very likely indicate what the basic problem is anyway.

FWIW with some good test signals, once you get used to them, its
surprising how ~ accurate the ear is, identifying problems is easy,
fixing them no so easy.

rgds, sreten.

Zaph|Audio
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[speaker dave]

Originally Posted by speakerdoctor

Here's another tool you might consider if you're building a number of different designs and, if you don't want to go the measurement route and rely strictly on your ears. If things work out right, you could voice a speaker before installing the xover in the box. They are sometimes available for <$100 on *bay.

http://www.vidsonix.com/vidsonixnew/boxlit2.pdf

What and forego the pleasure of sitting on the floor with an old cardboard box full of parts?

We use to have a large cart at JBL that had crossover layouts on a plexiglass panel, plus switchable inductors, caps and resistors, plus a bunch of banana plug wires so you could set up a topology and tweek to your hearts content.

"Sitting at the console of the might Wurlitzer", John Eargle would say when he saw us using it. Very handy.

And for tinitus: which crossover component impacts "phase and timing"?

David S.