Speak To Me Like I'm Six

[MiniVanMan]

Wow, new here, and there's way more information than I can possibly filter. Let's call this the next step in my evolving understanding of audio in general. In other words, thanks to all of you I'm about to annoy the hell out of

I can build a crossover. I can build a box. Ported, sealed... no problem. I can handle the design (or so I thought).

I want to design a HT system. I also want said HT system to be quite capable of quality music reproduction. Designing a set of monitors is not beyond my ability. However, in my world, unless I totally overcomplicate anything I touch, I'm not happy, until that overcomplication has driven me to tears.

To further complicate the issue, I have a wife, who has recently acquired a new home, that she graciously allows me to sleep in. That being said, WMMTMMW towers are probably not going to fly. I'm pushing it with my 4 cuft 15" Avalanche subwoofer sitting in the corner.

Okay, here are the real questions. The receiver I'll be using is a Yamaha RXV-1500. 120 watts per channel at 8 ohms. Doesn't seem to be a receiver that can handle a 4 ohm load. I'd like to do a dual woofer design. So I was wondering what the effects of putting two 4 ohm woofers in series are? Is this a good idea or a bad idea for MTM towers? Would I be better off designing a 2 way TM tower with an 8" driver??

Also, when building satellites, is there a rule of thumb on how you want to match them up with your fronts?

Next, you guys are killing me with the center channel. Reading through this forum I have NO idea where to begin in designing a center channel. Remember, can't be an eyesore.

And finally, I would like to be able to tell the wife when all is said and done.... "Look honey, I hardly spent any money at all." (as the repo guy is taking her car away).

So that being said, Dayton drivers are probably the way to go. I can play around with that a little, but I'd need to be convinced that I'd get double the quality for double the price.

Sorry this is so long. But it's the first step in my education process. As it turns out, designing a decent set of speakers is not about throwing together a box, screwing down some speakers, and soldering on a few caps, inductors and resistors.

Thanks All,

P.S. Oh, and what the $*#! is baffle step compensation????

[Svante]

Originally posted by MiniVanMan P.S. Oh, and what the $*#! is baffle step compensation???? [/B]

The baffle step is an increase in level of 6 dB towards higher frequencies that is a result of that the loudspeaker radiates in half space there, but in full space at low frequencies. If you do not consider this in your system design you will end up with a system with weak bass.

You can simulate this with my baffle step simulator "The Edge" in my signature.

[paulhfx]

Originally posted by MiniVanMan

Okay, here are the real questions. The receiver I'll be using is a Yamaha RXV-1500. 120 watts per channel at 8 ohms. Doesn't seem to be a receiver that can handle a 4 ohm load. I'd like to do a dual woofer design. So I was wondering what the effects of putting two 4 ohm woofers in series are? Is this a good idea or a bad idea for MTM towers? Would I be better off designing a 2 way TM tower with an 8" driver??

Two 4 Ohm woofers in series will provide a nominal 8 Ohm speaker (relatively easy to drive), with higher power handling capacity but no increased efficiency that paralelled woofers provide.

If I were doing an mtm I'd want the increased efficiency that paralell woofers provide, and if I couldn't get that I'd go with a a single 7" or 8" driver instead. There are other reasons/considerations for doing and mtm (like reduced vertical dispersion) but this is just my 'vote'.

Also, when building satellites, is there a rule of thumb on how you want to match them up with your fronts?

Most of the comments I've read, and my own personal listening experience, say that while the perfect setup would have identical speakers all round, the matching of the three fronts is far more important than matching the surounds to the fronts.


Check out jonmarsh's designs at htguide for some current and ongoing dayton designs.

Paul

[Svante]

Originally posted by paulhfx
[B]

Two 4 Ohm woofers in series will provide a nominal 8 Ohm speaker (relatively easy to drive), with higher power handling capacity but no increased efficiency that paralelled woofers provide.

Hmm, this is not right. The efficiency will increase by 3 dB for every doubling of the number of drivers*, regardless of if they are connected in series or in parallel.

Maybe you mean the sensitivity, which when expressed in dB @ 1m, 2.83 volts, will increase by 6 dB when connected in parallel, but by 0 dB when connected in series.

*This holds for any reasonable number of doublings, of course the efficiency can never go beyond 100%.

[paulhfx]

Correct Svante - thanks - my mistake - gotta watch those posts before I've finished my first coffee.

Paul

[MiniVanMan]

Thanks guys. I've downloaded your program Svante and will now begin tearing my hair out trying to understand it. It's what I live for so it's all good.

Anyway, now that we've established a 3db gain, which is what I assumed. How does setting up two speakers in parallel effect the Le and Re of the coil. Specifically, when designing a Zobel do I go off of single driver specs or do they double?

[Svante]

If the drivers are mounted in parallel, Le and Re is halved, so in the zobel, R should be halved and C doubled.

[Etacovda]

Svante - why does your edge software try to connect to a website? checking for a new version?

thanks for the software, very interesting... (now to figure it out too, lol)

[pinkmouse]

MiniVanMan

You might want to look at this thread, you might pick up a bargain.

[Svante]

Originally posted by Etacovda
Svante - why does your edge software try to connect to a website? checking for a new version?

thanks for the software, very interesting... (now to figure it out too, lol)

Yes, it is checking for a new version by fetching a text file containing the latest version number from my web server. If you are uncomfortable with this, you can disable this function on the help menu.