Mini statements & center channel - few questions

[nielvm]

Hello,

A while back, I built myself a surround sound system containing a statement center channel, mini statements (fronts) and 4 surrounds with a single tangband driver.
Overall I am very satisfied with the result. I hereby want to thank Curt & Jim for the elaborate drawings and explenation on their website. Just so you know, your speakers have made it al the way to Belgium :P.

The one thing that keeps bothering me, is that the center speaker does seem to require a lot of equalizing from audyssey xt32. The sound of the center seems inferior to the sound of the mini statements. With audyssey it sounds pretty good, but it doesn't seem as spatial as the mini statements.

As you can see, Audyssey has to add quite a bit of gain around the two cossover points. I tripple-checked all the connections and wiring, I'm pretty sure I did everything according to plan.


My questions:

- What could be the reason of the necessity of the audyssey gain arround the crossover points?
- Would upgrading the center to the closed 2RCC design possibly solve my issue?

[Jim Holtz]

Hi Nielvm,

The Mini's look great!

I'm not sure I'm going to be a lot of help due to the fact I don't use any room correction software in my pre/pro. I'm a Luddite and balance my system using the old fashion DB meter. I get called to friends homes to balance their HT sound systems after they become frustrated with the automated systems.

So, some thoughts;

The signal to the center is mono and will not have a lot of spacial information on most movies because it carries 70% of the dialogue. I don't do surround music so I can comment on that.

Frodaddy's center would add to bass impact if you're running your center full range. If you're crossing it at 80 Hz. it'll not add much if anything except some flexibility in placement since its sealed.

Sorry I can't be of more help. I ran the original Statements center for several years before I upgraded to Statements II mains and center.

Good luck!

jim

[nielvm]

Hi jim,

Perhaps spatial is the wrong word to describe the problem. I'm having the feeling that the voices coming from the center "stick" to the center and lack some body.
In my case it almost seems like the tangband can't provide enough output compared to the daytons and fountek tweeter, and therefor audyssey has to boost quite a bit.

I was thinking the 2rcc would be a possibility because that center uses 2 tangband drivers. I would however change the dayton 225's with my 180's, no problems there...

[Jim Holtz]

Hi jim,

Perhaps spatial is the wrong word to describe the problem. I'm having the feeling that the voices coming from the center "stick" to the center and lack some body.
In my case it almost seems like the tangband can't provide enough output compared to the daytons and fountek tweeter, and therefor audyssey has to boost quite a bit.

I was thinking the 2rcc would be a possibility because that center uses 2 tangband drivers. I would however change the dayton 225's with my 180's, no problems there...

I assume we're talking about movies. The whole purpose of the center is to anchor the sound to the screen for localization. The way you're describing the sound is the way DD processors are supposed to work.

Have you tried using test tones with a db meter to see how the center balances to the mains?

If the mid isn't balanced to the ribbon/woofers, it's a crossover issue. The center is quite musical and will sound very similar to the Mini's when music is played through it. Another test is to connect it as one of the main speakers and play some music and see if it still sounds unbalanced.

What are you using for amplification/processor? Have you double checked the processor settings?

EDIT: One more question. Is there anything blocking the back sound wave of the center? It has the same placement requirements as the rest of the Statements speakers. If the TV is sitting on top of the center, it'll block the mid back wave and make the sound unbalanced.

Jim

[nielvm]

Yes, I'm talking about movies.

I'm using a denon x4000 receiver. I will post some measurements tomorrow.

The center is located underneath a projection screen, about 30 cm from the back wall (1ft). Perhaps not ideal for the statements, but for the mini's this doesn't seem to be a problem.

If I use test tones to set the gain level of the speakers, the center seems to be way to quiet. I have already upped the gain of the center about 3db to compensate the "loss", but the center keeps lacking body.

Again, I'm very satisfied overall, but It bothers me that audyssey has to correct a whole lot for it to sound optimal. Without audyssey, the center lacks too much.

A very important detail I forgot to mention: I had to use the sdf version of the tangband. For the mini's I was able to buy the sd version. I already tried one of the sd tangbands in the center, but it makes very little difference, it barely makes a difference in the measurements (will post this tomorrow as well...)

Thank you very much for thinking with me. The larger 2rcc (but with 180's) still seems a nice upgrade for me. This solves the possible problem with placement and the 2 tangbands will give me a bit more possibilities in de midrange.

[kevinm]

Hi nielvm,

I'm not an expert and have no input on the theory, this is just personal experience.

I was in the same boat as you - the original center had a "voices in a box" sound. Like it was struggling to pair with the L&R. Even when I used a lot of EQ to get it close, I always felt like my CC could use more "oomph." So I built the Statement Center II and have been very happy with it. I still have to EQ it a lot (I think I am battling bad room interference), but overall it has made a very positive change.

[nielvm]

Hi kevinm,

You mean the statement with the vifa mid? Is the difference that great? How is the pairing with the statements with tangband drivers?

Sure, a part of the eq is due to room modes. If you see the eq of my fronts, that seems to me as normal correction for the room interference. Looking at the eq for the center, it looks like it isn't only the room modes that are corrected.

[kevinm]

Yeah, I built the center with (2) of the Vifa mids. I also upgraded my statements to the Vifas, so can't comment on the pairing.

I would like to note, from my experience, I doubt the EQ needed for you center would change (unless you have something blocking the back sound waves as Jim noted) - but it would probably sound better. I agree with Jim regarding why your receiver is applying so much EQ - it is probably related to placement.

[nielvm]

That's why the closed 2rcc would be an almost certain upgrade for me. 2 tangband drivers and no back tunnel...

[Jim Holtz]

That's why the closed 2rcc would be an almost certain upgrade for me. 2 tangband drivers and no back tunnel...

Considering your placement and that you have a SDF driver, I'd suggest you build the Frodaddy center. Curt doesn't recommend using SDF drivers with open back due to the magnet and tunnel size. You add in the screen and I'm not surprised you have recessed mids. Froddy center should solve your problems.

Jim

[nielvm]

Interesting... It is true that the sdf driver uses up a lot of the tunnel space. Using a sd driver doesn't seem to be the immediate sollution, but all things considered, the frodaddy center seems a wise (and not that expensive) update.

[nielvm]

I'm drawing the design for my closed center channel. As said above, I will make a copy of the 2rcc center, but I want to recover my RS180's so I don't have to buy 2 RS225's.

According to dayton, the 180's only need about 0,16ft3 per driver in a closed design. To obtain this, I will have to make a very wide but shallow center, or I would have to fill up the dayton enclosers with extra MDF.

A first design:



The alternative would be to vent the daytons, but then I would have to provide a bass tube each of about 2 inches diameter. In that case, the air velocity would become too high I'm afraid...


Any thoughts?

[nielvm]

Or possibly a vented design more like the original center layout?

2 midwoofers in a sealed enclosure, tweeter in the same room as the daytons and behind the tweeter the bass port?

[nielvm]

This design seems better. The box is vented for the daytons, the volume of the dayton enclosure is about the same as the original statement center and the volume for the tangbands is the same as the 2RCC design.

[nielvm]

Done😊

It sounds a lot better, and audyssey doesn't have to correct that much anymore. Mission accomplished!

[Philzeemon]

What size is your port/vent for your center channel using the RS-180's? Is the material PVC pipe? Wouldn't mind seeing an updated graph of its performance, Thanks

[nielvm]

I used this vent:

http://www.monacor.co.uk/products/speakerbuilding-bassreflextube/vnr/128630/

Haven't done an impedance measurement yet, but I think the size of this tube will be about right to tune this center to 40-45hz.

The improvement in sound quality (in my situation) is above expectation.

[jameswang]

Haha...It's beautiful. Just wondering how much you spent on all these parts.

[nielvm]

All together it would be about 400 euro I think...