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Post by garbulky on Mar 23, 2012 3:40:52 GMT -5
Newbie question:
I have a UPA-2. I plan to someday purchase a more powerful emotiva X-series amp, and use the UPA-2 to power the surrounds or a center. Maybe pull off bi amping duties on my m80's.
If they are run off the same source will I have an imbalance in volume due to the UPA-2 having less power? I'm talking at moderate volume levels, not at levels where the UPA-2 will be hitting its limits.
If so, is there a way to get around this more or less conveniently?
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Post by wizardofoz on Mar 23, 2012 6:43:33 GMT -5
Sticking with say upa series amps there should be no issue. The upa-2 has some adjustments on the rear that will allow some level matching. Using the upa-2 for centre will leave one channel spare unless you biamp it. Using a couple of upa-1's for LR might work ok or maybe better using an xpa3 for the LCR and use the upa-2 for the rears, assuming only 5.1 needs
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Post by garbulky on Mar 23, 2012 7:17:45 GMT -5
I appreciate the response wizardofoz.
I might be wrong but I don't think the level matching using the rear knob on the UPA-2 will help as it will be the least powerful amp in the setup. I also tried the level nob and I found for some reason it reduced the quality of the sound (very subtly) to my ears when turned down to a significant amount, so I would prefer to use that as a last option though it is convenient.
My main question, is when I turn the volume up on, say the XDA-1, will differently rated powered amps still output at the same volume level if connected to the same source?
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geebo
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Post by geebo on Mar 23, 2012 7:34:09 GMT -5
Amplifier gain is the issue here. Emo amps are fairly high at 32 and the knobs on the rear will adjust the gain down. Since all the Emos have the same gain, you'll be okay. And if you get an amp with lower gain, regardless of its power output, turning the gain down on the UPA will match the levels. Also don't forget that just about any multi channel processor will allow you to match levels.
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Post by garbulky on Mar 23, 2012 9:42:48 GMT -5
Thanks. Geebo. That's a little too technical for me to process.
Are you saying (for extreme comparison) that if I had an XPA-1 powering one speakers and a UPA-1 powering the other, that as I turned up the volume on my XDA-1 or pre-amp as long as it was within the power range of the UPA-1 the volume levels on the two speakers would be matched because the amps use a similar "gain" circuit? As in one speaker would not sound inordinately louder than the other one?
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geebo
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Post by geebo on Mar 23, 2012 9:53:35 GMT -5
Thanks. Geebo. That's a little too technical for me to process. Are you saying (for extreme comparison) that if I had an XPA-1 powering one speakers and a UPA-1 powering the other, that as I turned up the volume on my XDA-1 or pre-amp as long as it was within the power range of the UPA-1 the volume levels on the two speakers would be matched because the amps use a similar "gain" circuit? As in one speaker would not sound inordinately louder than the other one? If all speakers are of the same efficiency, yes. But again any multi channel processor I can think of will have a means to match levels anyway. |
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Post by garbulky on Mar 23, 2012 10:16:23 GMT -5
That is great news. That means I don't have to chuck my UPA-2 someday. I'm very happy with it now but with it not being sold anymore, I was despairing of being able to upgrade my system while still holding on to it.
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hemster
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Post by hemster on Mar 23, 2012 21:44:19 GMT -5
I think if you did decide to part with your UPA-2 (why would you?), it will get snapped up pretty quickly. These are sought after as they can be used to power the rears in a XPA-5/UPA-2 combo, which I have and love. I'm keeping my UPA-2.
Edit: The Emporium has the occasional UPA-2 but it goes quick!
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Post by RightinLA on Mar 23, 2012 23:02:00 GMT -5
The UPA-2 compliments the XPA amps just fine for surrounds as others have stated. The surrounds are usually a lot less demanding on an amp as the front speakers so there shouldn't be a problem at higher levels.
As Geebo mentioned, you can also adjust the relative levels to suit your ear with your receiver.
I also have the UPA-2 and really like it for a two channel system. There is always a place for a UPA-2.
I still find it difficult to understand why this wasn't a top seller for Emotiva, especially when it was better than the competition for a great price.
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Post by garbulky on Mar 23, 2012 23:48:13 GMT -5
Ok I think I've almost got this figured out. Please correct me if I'm wrong. It's a "gain" setting that governs how the amp responds to the volume input from the pre-amp. So even if an amp is much more powerful if they have the same gain settings, they will increase the volume at the same rate as another less powerful amp with the gain settings as long as the speakers are of the same efficiency.
Two things I still don't get:
1. If this is the case, then at the maximum gain setting, it possible for an amp that has a lot more power under its hood to get louder than the other amp if they both respond to the max gain setting at the same volume ? If so, how?
2. I still don't understand why I would have to turn DOWN the gain knob at the back on my UPA-2 to "level match" when it is going to be the least powerful amp in the set up. Wouldn't I instead need to turn the UPA-2 up somehow or the more powerful amp down instead?
Rightinla: I agree, I really don't understand how this wasn't the best seller. Plenty more people wanting to spend less cash for a good two channel amp on average!
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Post by knucklehead on Mar 24, 2012 0:21:23 GMT -5
Two things I still don't get: 1. If this is the case, then at the maximum gain setting, it possible for an amp that has a lot more power under its hood to get louder than the other amp if they both respond to the max gain setting at the same volume ? If so, how? 2. I still don't understand why I would have to turn DOWN the gain knob at the back on my UPA-2 to "level match" when it is going to be the least powerful amp in the set up. Wouldn't I instead need to turn the UPA-2 up somehow or the more powerful amp down instead? This is where room correction comes in with a processor or AVR. They level match each channel separately regardless of how much power the amp thats driving that channel is. Most have a range of -10 to +10db. More than enough range to compensate for more powerful amps and the variances between speakers. The difference in the db setting between the XPA-2 and a UPA-2 is only about 4db provided they are both driving identical speakers. At 100 watts output the UPA-2 might be providing 100db of sound which is very loud. The XPA-2 driving the same speaker at 200 watts would only be about 3db louder. It takes a doubling of power to net 3db gain. Amplifier power is not linear in the SPL it delivers. Its a logarithmic function. Similar to a car where 100hp might net you 100mph - 200hp won't get you to 200mph - more like 120mph - if that. Look at the cars with 500hp - top speed is usually less than 200mph. |
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