One speaker versus two

[Mos Fetish]

Howdy

Ever noticed how when you balance your system over to one channel, things don't sound right. Lack of bass. Lack of something indefinable?

Ok, you're missing the reinforcement of the bass and the other half of the stereo image. But, still, this is how we test. We measure. We use the software. We build temp xos and we listen.

But, we're listening to one speaker.

Question for the experienced heads here. How do you actually decide that things sound good (regardless of your simulations) when you only test with one speaker? Or do you just assume that the bottom end will beef up and the slightly annoying mid will clear up when you bring in the second speaker?

I've measured well. I've simulated well. I've got a good sound, but not a great bottom end and a slightly forward mid. Can I expect a radically different sound with another speaker in operation?

Sure it's easy to say: just build the other xo. Is that the answer? See my point?

Mos

[jomor]

I usually do a simulation and build the first speaker. I listen to it and try to figure out the tone balance, if it has too many highs, mids or bass.
I always try to keep the midrange 3dB lower than the rest of the band, since the walls early reflections (which will be double when the second speaker will play)
will enhance the mids. The human ear understands the early reflections (when there are walls close to the speaker) as a single wave, which makes us hear the
the mids stronger than we see them on measurement. If your room is small and you cant move the speakers at least 1m away from the walls, you should definelty
lower the mids at your design. If you have a zobel at your woofer, it will help you lower the mids easy, give it a try. The second part of the listening is the midrange clarity (talking about two way speaker)
It is critical for both drivers to be in phase at the crossover frequency. Reverse the tweeters polarity at your simulation and try to obdain the deepest cancelation you can at the crossover frequency.
This will make you sure that both the drivers will be in phase when the tweeters polarity will be correct (assuming that the measurements used at the simulation include the correct phase data of each driver)
When both drivers are in phase, this ensures midrange clarity ( quite more than magnitude flatness) and soundstage precision. So if your phases are good, and your tonal balance ok, it will sound good for sure.

Very interesting question you asked, I d like to read everybody's answers and see how everyone works on this.

[rabbitz]

Hi Mos.... long time no see.

I mix the stereo signal to a mono signal. If it sounds great in mono, then when the 2 speakers are done it will sound great in stereo... which is really 2 mono speakers working together.

I've always found mono the only way to test as I get confused easily with stereo due to the differences in the channels which can be misleading and makes it so much harder. Mono is a great tool for all sorts of things. My thoughts anyway.

Mono, mono, mono....... ah shutup.

[Mos Fetish]

Hi, Rabz, yes long time no post. Been busy with non-audio stuff.

Yep, I sort of agree about mono. It does solve the problem of loss of information. But, it can't give you that obvious boost in low bass that two speakers in one room will. Also, the stereo image is spatial, not at all like a point source from mono.

I may be just the sort of guy that has to build two xos for testing. Oh, woe is me :-)

Mos

PS: don't know if you're a rugby union fan but if so, we're gonna whip your butt in Sydney tonight :-)

[ShinOBIWAN]

Personally speaking I calibrate each speaker seperately.

I tailori the XO directly to the drivers in that particular cabinet. I use digital XO's so this is almost laughably easy to do. I simply measure one speaker tweak to a flat response and minimum phase then do the same with the other.

I'm over simplifiing somewhat to save turning this into a long and boring blow by blow account of how I do things but calibrating one speaker within a close tolerance of the other is the way that provides me with the best results.

BTW: Always make sure you run your drivers in before and xo work.

[rabbitz]

Originally posted by Mos Fetish
PS: don't know if you're a rugby union fan but if so, we're gonna whip your butt in Sydney tonight :-)

Er...um.... no comment. *%$!@ NZ Not a good year for Aussie Rugby.

I know what you are saying...... to me with 1 speaker you get a reduced SPL but by winding up the wick you still should get a similar bass performance. I use a mono speaker in the workshop and test rig and certainly not lacking in bass or tonal balance. Actually the setup went to stereo speakers today and the tonal balance is still similar. That spacial stuff confuses the hell out of me when testing and probably the main reason I use mono with a monople speaker.

You just want to build 2 xo's for testing don't you Mos

[DeonC]

Not a good year for Aussie Rugby.

Hehehehehe. Sorry. And we'll see you next Sat in Perth. I am looking forward to an awesome game, but I do sympathize. Until recently SA rugby was also like a brother in jail- you love him but you don't talk about him.

Deon

[rabbitz]

Aw.... go away.... not real optimistic on that game either

We shall return as there is only one way to go now... up.... I hope.

[rcw]

On the subject of the nether regions, Americans have buts but Australians have ***** and in the context of rugby the Australian **** is smarting rather a lot at the moment.

[Mos Fetish]

Since this has turned into a football thread, I'd like to make a prediction for the South Africa-NZ game in Dunedin this week & the Aussie-NZ game in Auckland next week:

P-A-I-N


Mos