340SE center

[davef]

Have you tried it with both positions of the EXBAC switch? You'll have to temporarily remove one driver to get to the xover. On the xover PCB there is a switch. Flip it to the other position and see if it helps. I think it's the right side midwoofer you remove looking at the baffle. I have a strange feeling this is your issue. Do the people's voices sound... "honky" ?

HINT when you remove a driver untap each screw half way. Slid driver out slightly so you can hold the edges of it's basket while it hangs on the screws.Then remove the BOTTOM ones first. Then remove the last two screws while holding the driver basket edges. Be careful not to hit the cone. It's center of gravity is a little weird for people that haven't handled a driver before.

GOOD LUCK!

HiroPro,

The EXBAC network on our 340SE/SEC crossover is not designed to be a user serviceable option. If a customer orders a 340SE "center", EXBAC is enabled by default and the speaker is tested as such.

That said, enabling / disabling this option is certainly not what is causing a lack of clarity on some source material at extremely loud volumes. Gov has had these speakers for a long time now and I do not recommend opening them up and disabling EXBAC as that will not resolve the issue.

The 340SE is on a mopad at the edge of the top HT equipment rack, just under my wall mounted plasma. I have a Pioneer Elite SC-05 that has a very robust ICEPower amp section. I am using the receiver's room correction and have engaged a slight x-curve. Dialogue at a loud volume seems to sound best this way.
I guess the best way to describe what I hear at times is a harshness with some movie soundtracks, again, only at very loud SPL's. I really do not think my receiver is running out of gas, since it is only dialogue understandability and not everything centered in the center channel. I am thinking maybe the 340 is at its limits or nearing it. I guess it would be hard to tell for sure

130 watts is not that much power, especially when considering that you are using auto room EQ. For example, even something as minor as a +6dB boost of EQ in a specific frequency range will change the available power in this frequency range from 130 watts to a measly 32.5 watts...

The key factor here is that it sounds fine at all volume levels -except- when played extremely loud and with only certain source materials... As an example, auto EQ will often try to compensate for the large dips caused by floor bounce, which are typically found between 200 - 600Hz (lower end of the vocal range). These dips can be huge so even if we assume that your receiver is only applying a small 6dB boost to this range (which is small in comparison to how deep these dips can be), at 12 feet back from the speaker, combining the wattage capability of your amp with the sensitivity of the speaker, your amp will be clipping in part of the vocal range at anything over 92dB. A level which I would consider to be loud, but quite tolerable. When class D amps run out of juice, they tend to sound very edgy and harsh...

I would recommend the following:

Turn auto EQ off then determine if you still hear the harshness using the same source material and same volume level. Granted, without auto EQ it might not sound as good overall, but we are trying to determine what is causing this so that I can make a qualified recommendation as to whether or not the forthcoming STC will fix the issue...

Using an SPL meter, measure the volume level at the listening position when you first start noticing the issue...

It is also important to consider that since this seems to only occur with certain source material, it could very well be an issue with the source material itself. You could also try swapping the center with one of your mains – just to eliminate the possibility that it could be a problem with the individual speaker.

Hope this helps!

[Gov]

Dave,

Excellent response, thanks! I will try your recommendations. I checked the amount of EQ MCACC is applying to the center channel and its adding quite a bit in the 120 to 250hz region (+6 and +4 respectively). The higher frequency regions, it is in the -dB ranges. The funny thing is that I am only noticing this problem with dialogue and otherwise, my system never sounds harsh or edgy. In fact, even in very dynamic scenes like "Transformers 3" it sounds great near reference level.
Also for the record, I always run the Ascends small with an 80Hz XOver since I use a SW.
I wonder if it is in fact my ICE amp running out of steam in the 120 to 250hz region. Maybe adding an Emotiva XPA-3 would help? Or just leave the EQ off so it does not apply any boosting to the speakers.

[HiroPro]

When class D amps run out of juice, they tend to sound very edgy and harsh...

Well it sounds like that could be it! Gov it looks like you like digital amps. Perhaps you should checkout www.classdaudio.com. They do make ready to use amps as well if assembly is to daunting. SDS-254 is jewl of the bunch.

BTW I've used the Ice modules and they don't sound as good as the IR amps to my ears. I also have used those Emotiva amps and love them. They are great "duty" and a good deal "for the money". I have owned/used the XPA series as well as the UPA-1 monoblocks.

Once I started building my own amps with the various kits/modules out there though... I haven't looked back. Even the gainclone chipamps can sound better than a lot of commercial retail stuff out there IMHO.

[HiroPro]

HiroPro,

The EXBAC network on our 340SE/SEC crossover is not designed to be a user serviceable option. If a customer orders a 340SE "center", EXBAC is enabled by default and the speaker is tested as such.

That said, enabling / disabling this option is certainly not what is causing a lack of clarity on some source material at extremely loud volumes. Gov has had these speakers for a long time now and I do not recommend opening them up and disabling EXBAC as that will not resolve the issue.

The off chance idea I had was perhaps it's set to disable on the xover by mistake before it shipped. What he described sounded a lot like midrange diffraction losses. It now sounds a lot more likely his amp is running outta poop.

Curious which direction of the switch is for enable? When I looked at it I tried the non factory setting with it in a wall console and it hurt the midrange. I flipped it back to factory default but because they were not my speakers and it was some time ago I can't remember which direction is enabled.

[Gov]

Dave,

Initally I was incorrect. My auto EQ put a +8dB on the 125Hz band and a minus 0.5dB on the 250Hz. At -5dB MV from reference, I was getting about 87dB on the SPL meter for dialogue from my 15' listening position. I was using "The Wolf" scene in Pulp Fiction BD for the test. It sounded a bit edgy/honky especially when Sam Jackson was speaking. I lowered the 125Hz band to +4dB from +8 and engaged THX post processing. This seemed to help.

I did try it with the EQ completely off and it sounded much brighter and tinny. Did not like the sound much that way. It did help the dialogue issue though.

It is my understanding the most male vocals fall in the 125Hz area so I guess this would make some sense.

Looking forward to any further comments, thnx

[HiroPro]

Gov have you considered some type of acoustic isolation of the center and perhaps lilting it's axis?

Auralex SpeakerDudes HD, Auralex Mopads or ISO Wedges might help. They will isolate the center from your AV console and also allow you to tilt it. You can use a thin piece of foam as well to break the baffle coupling diffraction losses. It's that black foam with very visible bubbles/holes that Raal uses to tweak their other tweeters. If the speaker was sitting on that and the foam protruded past the axis of the front baffle/TV stand the it would break up the midrange coupling to the extended front baffle affect. I'm not sure on what axis this occurs. I would think it would be the vertical axis as that's where the baffle is extended. And it's downwards so that's perfect. You can decouple the center and also prevent those extended baffle issues in one shot. You also might find if you move the center so that it protrudes past the vertical plane of the TV stand that's acting to extend the baffle it might help. Move it 1/2" to 1" past this plane. It should help decouple the midrange from the artificial extended baffle.

It is possible though it's your amp as Dave has suggested. Does it have pre-outs? Perhaps you can try/borrow an amp to see! If you post pictures of the room then we will have a better idea of what is happening acoustically. Please post pictures. What you describe can be both acoustics IE your room and also, and I've experiences this as well with ICE, those modules are running outta juice/poop and your getting distortion. Dave's speakers are efficient/sensitive and can produce ear damaging SPL with relative ease in my experience. You must be talking some serious SPLs.

I would take pictures and video to show us.

[Gov]

Gov have you considered some type of acoustic isolation of the center and perhaps lilting it's axis?

Auralex SpeakerDudes HD, Auralex Mopads or ISO Wedges might help. They will isolate the center from your AV console and also allow you to tilt it. You can use a thin piece of foam as well to break the baffle coupling diffraction losses. It's that black foam with very visible bubbles/holes that Raal uses to tweak their other tweeters. If the speaker was sitting on that and the foam protruded past the axis of the front baffle/TV stand the it would break up the midrange coupling to the extended front baffle affect. I'm not sure on what axis this occurs. I would think it would be the vertical axis as that's where the baffle is extended. And it's downwards so that's perfect. You can decouple the center and also prevent those extended baffle issues in one shot. You also might find if you move the center so that it protrudes past the vertical plane of the TV stand that's acting to extend the baffle it might help. Move it 1/2" to 1" past this plane. It should help decouple the midrange from the artificial extended baffle.

It is possible though it's your amp as Dave has suggested. Does it have pre-outs? Perhaps you can try/borrow an amp to see! If you post pictures of the room then we will have a better idea of what is happening acoustically. Please post pictures. What you describe can be both acoustics IE your room and also, and I've experiences this as well with ICE, those modules are running outta juice/poop and your getting distortion. Dave's speakers are efficient/sensitive and can produce ear damaging SPL with relative ease in my experience. You must be talking some serious SPLs.

I would take pictures and video to show us.

I would post a few pictures but I have to figure out how to reduce the image quality so I can upload them here. I am not very computer savvy I am afraid. I will work on it.

[HiroPro]

I would post a few pictures but I have to figure out how to reduce the image quality so I can upload them here. I am not very computer savvy I am afraid. I will work on it.

Google Faststone Image Viewer. It's FREE!

Also photobucket.com is a great site to upload photo for use online.

[Gov]

Google Faststone Image Viewer. It's FREE!

Also photobucket.com is a great site to upload photo for use online.

Thanks, how is this? These were taken from the couch which is 15' away. Yes, X-Mas decoration on the 340SE center.

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[curtis]

First off, try moving the center forward to the front edge the the stand.