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Post by Boomzilla on Jan 26, 2013 22:06:17 GMT -5
If you can, try moving your speakers out a bit from the wall. Should make a SIGNIFICANT difference in bass response.
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Post by yves on Jan 27, 2013 3:20:36 GMT -5
i don't know what happened i'm a little confused. aren't my 200 watts max 8 ohm speakers suppose to give up before my 300 watts amp? why did increasing the bass in my receiver caused my amp to clip? The product page doesn't say they are "200W max 8 Ohm" speakers. Instead, it just tells you how much power amplification is recommended. Meaning, there is no real method to find out the exact figure, as these kinds of recommendations vary from manufacturer to manufacturer. This article tries to explain why. www.prestonelectronics.com/audio/Speakers.htmSo, as you can see for yourself, driving a power amp into clipping can kill your tweeters if you don't know what you're doing. Personally, I, would never drive my XPA-2 into clipping, not just because driving a power amp into clipping can cause loudspeakers to suffer, but also because it causes distortion, which simply doesn't sound very good. Just because you cannot hear any distortion, doesn't necessarily mean distortion isn't there. Most commercial pop music available on CD nowadays contains enormous amounts of distortion. Further, too much distortion can drive a power amp into clipping, which then causes even more distortion. That being said, I have seen the LED meters on my XPA-2 jump up to 10 without driving it into clipping. At about 10 feet (just over 3 meters) distance from my speakers, even though my speakers are less sensitive than yours (mine are only 88.5 dB, whereas yours are 90 dB, according to specs), the sound was so loud that turning up the volume any higher could result in permanent ear damage. My speakers are rated 340W at 4..8 Ohm (180W RMS). |
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johto
Minor Hero
Posts: 14
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Post by johto on Jan 27, 2013 4:25:12 GMT -5
Something wrong with your setup! I cant believe you can run clean (flat non EQ'q, no bass boost) signal with full power with your speakers being 90db sensitivity. That would mean, even with with one (1) watt it should produce 90db measured from one meter !
I have been using my xpa-2 with my KEF Q900 speakers, now about 1-2 weeks. I have normal apartment livingroom (about 15x20 feet) , and not have even the SECOND LED lights up even on a normal listening. Not even on the loud parts!
I just for the heck of it, just now dialed my preamp/dac's master volume to the levels that the leds starts to dance, and HOWLY sh**!!!! The sound was pure and non distrorted(awesome) but the cops would be here so fast if i had left the volume like that more than couple seconds. My ears would be ringing and busted too !
Either you are deaf, your room is way too big, or your gear is not setup right. Something is a miss imho.
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Post by garbulky on Jan 27, 2013 4:34:25 GMT -5
Here's am easy way to check. Hook up your laptop to the xpa-2 from its headphone output and then see whether it is not distorting. Just keep in mind that a laptops outpu isnt going to be good at all but it will let you figure out the volume issue.
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Post by garym on Jan 27, 2013 23:06:02 GMT -5
I'm having a problem with my XPA-2 similar to the OP's. My amp does not clip on heavy bass material played loud; it trips the protection circuit.
As soon as I got it hooked up (about 3 weeks ago) it seemed to me that the amp was working too hard --- for a 250W amp --- to produce the levels (for rock) I usually set. On my Denon receiver that level = 0db (which I believe = 85 db absolute).
On the XPA-2, the setting on the UMC-200 needs to be 60 to achieve that level. I discovered that you can boost the preamp signal to the amps, so I boosted it 5db. That allowed me to reduce the volume setting to 55 to achieve the desired level.
That works OK on most material, but on any material with heavy bass (such as Madonna's "Vogue"), the amp trips into protection.
Today I measured the output of the amp with a DMM, to see what setting was needed to produce the standard 2.83V speaker voltage with a 1K test tone. Left channel was 53.5 (to get 2.84V), the right was 52.5 (to get 2.73V).
Do those settings seem normal to others with this amp?
BTW, the protection seems to be triggered by an over-current, rather than over-temp. When it trips, the amp is cool to the touch, as cool as any other metal surface in the room.
Any thoughts?
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KeithL
Administrator 
Posts: 10,261
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Post by KeithL on Jan 28, 2013 0:09:39 GMT -5
The protection in our amps is sensitive to several different fault conditions.... including DC or ultrasonic noise on the input, faulty grounds on the input, excessive clipping on the output, intermittent connections in the speaker itself, and even the speaker itself bottoming out (as well as the usual overheat). If your source device is clipping heavily, or putting out DC, or if your speakers themselves are bottoming out, the XPA will go into protect. I'm having a problem with my XPA-2 similar to the OP's. My amp does not clip on heavy bass material played loud; it trips the protection circuit. As soon as I got it hooked up (about 3 weeks ago) it seemed to me that the amp was working too hard --- for a 250W amp --- to produce the levels (for rock) I usually set. On my Denon receiver that level = 0db (which I believe = 85 db absolute). On the XPA-2, the setting on the UMC-200 needs to be 60 to achieve that level. I discovered that you can boost the preamp signal to the amps, so I boosted it 5db. That allowed me to reduce the volume setting to 55 to achieve the desired level. That works OK on most material, but on any material with heavy bass (such as Madonna's "Vogue"), the amp trips into protection. Today I measured the output of the amp with a DMM, to see what setting was needed to produce the standard 2.83V speaker voltage with a 1K test tone. Left channel was 53.5 (to get 2.84V), the right was 52.5 (to get 2.73V). Do those settings seem normal to others with this amp? BTW, the protection seems to be triggered by an over-current, rather than over-temp. When it trips, the amp is cool to the touch, as cool as any other metal surface in the room. Any thoughts? |
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Post by garym on Jan 28, 2013 0:32:19 GMT -5
The protection in our amps is sensitive to several different fault conditions.... including DC or ultrasonic noise on the input, faulty grounds on the input, excessive clipping on the output, intermittent connections in the speaker itself, and even the speaker itself bottoming out (as well as the usual overheat). If your source device is clipping heavily, or putting out DC, or if your speakers themselves are bottoming out, the XPA will go into protect. Thanks, Keith. The input is the UMC-200. The source is a Sony BDP-S580 player. So if there is DC or ultrasonic the UMC-200 would be the source, unless the pre is passing it along from the Sony. There is no audible clipping in speakers when the protection trips; they sound fine. Do those measured voltages/level settings seem normal? (I'm wondering if there may be some internal short in the amp). |
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Post by garbulky on Jan 28, 2013 5:33:09 GMT -5
What are your speakers gary? The axiom audio m80's had an issue with tripping the xpa-2 during loud passages because their impedance dropped to very low values causing the xpa-2 to go into fault protection. Though I believe this has been fixed or is fixable...
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Post by davidgonzalez on Jan 28, 2013 9:07:36 GMT -5
what's the difference between the amp clipping and going into protection mode? so my amp to went into protection mode too?
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Post by garym on Jan 28, 2013 10:05:48 GMT -5
What are your speakers gary? The axiom audio m80's had an issue with tripping the xpa-2 during loud passages because their impedance dropped to very low values causing the xpa-2 to go into fault protection. Though I believe this has been fixed or is fixable... The speakers are KLH AV-5001s. Mid-90s vintage. These are floorstanding 3-ways with a 12" woofer, 12" passive radiator, 5" cone mid-range and 1" dome tweeter in a sealed box. Rated at 8 ohms nominal and 90 db sensitivity. The impedance drop you suggested is quite possible. The speakers are quite old, and its possible some of the crossover caps have gone off-spec. They sound fine, however. The bass they produce is very tight, and they can reach down to about 28Hz. There is no need for a sub for any musical material with these speakers. They will bottom out with LFE signals from some movies, though. I'd like to confirm that the amp is OK before tearing into the speakers, or replacing them. I hoped someone would comment on the voltage measurements I gave to let me know whether they seemed normal. |
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Post by garym on Jan 28, 2013 10:07:19 GMT -5
PS: Garbulky ---
What was the fix for the Axiom prob you mentioned?
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Post by garym on Jan 28, 2013 10:12:40 GMT -5
David,
When the amp trips into protection it shuts down, the power LED goes orange and the "meter" LEDs go red.
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Deleted
Deleted Member
Posts: 0
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Post by Deleted on Jan 28, 2013 11:52:44 GMT -5
ok so i did something im not very proud, i fiddle with the tone control and adjust the bass to +4. I made sure my b&w where able to handle it, they did. i have to say thats is impressive the amount of bass that this speakers where able to handle, the cones where moving like crazy and there was absolutely no hint of distortion. They really are something i was listening to the same volume level that i have listen to my music since i got my xpa-2 almost 2 months ago and during the 6th song the amp clip :/. i turned it off and on again just to make sure everything was okey and it was. i have to say that the bass was very satisfactory and those 6 songs i heard really made me think for the first time that i didn't need to buy a subwoofer but now i think i have to buy a pair of xpa-1 ?? i don't know what happened i'm a little confused. aren't my 200 watts max 8 ohm speakers suppose to give up before my 300 watts amp? why did increasing the bass in my receiver caused my amp to clip? David, you are a bad boy! ;D Turn that bass control back down and don't touch it again. Plus 4 takes huge amounts of extra amp power. If you have a sound meter you can determine how many dB's increase the + 4 setting is. If it is 4 decibels then by using +4 on the bass knob you have now turned a 300 watt/ch at 8 ohm amp into about a 120 watt amp, effectively. What you need instead of wasting your hard earned money on a MF DAC (which might make a very slight difference if at all) is to use your sub. If you do not have a good sub then buy one (and I mean good sub) instead of DAC's to start with. The 683 is a nice speaker but not designed to play at party levels with + 4 bass. With the B&W's crossing over to a sub at 70-80 Hz the load on your amp will be relieved, you will stop clipping and have clean and deep bass if you play as loud as you seem to. The headaches are from listener fatigue caused by distorted sound either from over driving your amp or distortion in your speakers. IMO your are placing too much emphasis on the components like DAC's and even the amp on the bass performance, etc. The main issues are your speakers, how they are placed in your room, the source and making sure you have enough headroom in your amp. In your case you are overdriving speakers with two 6.5" woofers to try and attain loud playback with the bass controls turned up. High quality amps like the Emo XPA-2 and those form Parasound, etc. all have ruler flat response down to 20Hz or below. The bass performance of the XDA-2 is said to be super by its owners. That is because it puts out more than 300 watts/8 ohms and 500 watts/4 ohms. That in most cases is fine for the 683. If you need more bass look to a better speaker for the low bass or better yet, add a great sub. |
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Post by savjac on Jan 28, 2013 12:29:12 GMT -5
Chuckie did good in his answer and I would recommend following it to the letter. Before my Martin Logans I too had B&W's although I have never changed the tone controls one mm, as a matter of fact, all tone controls are defeated. None the less, my XPA's have never provided a shut down or even a whisper of trouble no matter what I through at them. I can say that unless you have gone into the Denon set up menu and lowered the internal volume output manually, turning the volume knob to zero is WAY WAY above what one would ever expect to listen to. That volume setting with the Emo will cause it to go into shut down as it is protecting your speakers from shredding and becomming umbrellas. Dont go by what the web says in way of zero db and all that crap, those numbers are all different on each processor out there and has to be adjusted in the set up menu first. If I can guess I would say you were well into the 105db range with those speakers and amp before you turned up the bass.
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Post by garym on Jan 28, 2013 13:44:43 GMT -5
I can say that unless you have gone into the Denon set up menu and lowered the internal volume output manually, turning the volume knob to zero is WAY WAY above what one would ever expect to listen to. You may be confusing two different posts, davidgonzales' and mine. David is using an Onkyo receiver for his preamp. I'm now using the Emotiva UMC-200. Before buying the Emotiva gear I used the Denon. On Denons, the "0 db" setting corresponds to the full power of that amp, which was 90W for mine (AVR-1712). denon.custhelp.com/app/answers/detail/a_id/136/~/relative-and-absolute-volume-rangesWith the 250W/channel Emotiva amp I expected to have a lot more headroom. But it trips protection at about the same level I used to run the Denon. |
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lowepat
Minor Hero
Forget to include. All packing items in the original box will be included.
Posts: 27
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Post by lowepat on Feb 4, 2013 21:04:07 GMT -5
I am new here. I appreciate any advice for the following: I plan to up grade my XPA-2 to three XPA-1 for my all front speakers. Before decision, could it be possible to use the XPA-2 as mono for 4 OM speaker (actually the center speaker) then I need only two XPA-1. Thank you.
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Post by geebo on Feb 4, 2013 21:33:15 GMT -5
I am new here. I appreciate any advice for the following: I plan to up grade my XPA-2 to three XPA-1 for my all front speakers. Before decision, could it be possible to use the XPA-2 as mono for 4 OM speaker (actually the center speaker) then I need only two XPA-1. Thank you. That would be the equivalent of driving 2 ohm speakers in un-bridged mode. I wouldn't do it. |
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Post by AudioHTIT on Feb 5, 2013 0:40:06 GMT -5
I am new here. I appreciate any advice for the following: I plan to up grade my XPA-2 to three XPA-1 for my all front speakers. Before decision, could it be possible to use the XPA-2 as mono for 4 OM speaker (actually the center speaker) then I need only two XPA-1. Thank you. Yeah, I wouldn't try it either, sell the XDA-2 and have three matching amps. |
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Post by leadliner on Sept 16, 2013 17:34:55 GMT -5
maybe try heavier gauge speaker wire.also what type of breaker are you plugged into 15 a
or 20 amp breaker just courious.
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Post by leadliner on Sept 16, 2013 17:37:31 GMT -5
i also seen the read lights on my xpa2 listening to pink floyd the machine on sacd :)it was insane thow.
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