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Post by fusioneer on Nov 22, 2014 12:47:52 GMT -5
I was thinking about the bi-amp. I've read that this won't get me extra power, but I'm not sure I understand why not. I understand all channels share the same power supply, but the fusion is rated at 2x110W and 7x65W. Now, unless my calculator is sneakily depleting my scotch stash, one number is actually smaller than the other in spite of the same power supply. So, something doesn't add up. I'm hoping someone can explain. Do you notice a difference with the volume setting needed when bi-amped as opposed to not bi-amped? Well, some who espouse that view have this over-simplified view of wattage working like water through a pipe, i.e. the amplifier pushes it blindly and what isn't used in each subspeaker's spectrum gets dumped in the crossover as heat. This is nonsense, but I've heard it said. Others point out that the woofer and tweeter have very different requirements and because of that you don't get double the power. This is true. E.g. if the tweeter uses 1/4 the power of the woofer, you only get about 20% higher before the amplifier powering the woofer starts limiting. So your 110wpc amp gets about the same headroom as a 132wpc amp, which is something but if you do need double the power you'll just have to buy 200wpc. If someone offered that with the size and heat dissipation of the Fusion, I'd get it but fat chance. Now if you ran into the power supply limit (re your calculation), you'd get no advantage at all, but as it is you do raise the per-channel ceiling a bit. Here's what I was saying about my bi-amping in another post: Wanted to add my data point on bi-amping -- I run it on my Fusion and it works fine. It does seem to make a bit of difference though I couldn't swear by it, it takes too long to rewire and I lose confidence in comparisons made a few minutes apart. I'm not able to max out the volume of the Fusion with my place & ears (like the poster above), so I don't know if it pushes the limit further, nor do I care. Moreover, I asked Chad from Emotiva support whether it's a good idea and he said why not, it can only help. I asked because I wasn't sure if there were specifics of the Fusion that would make it counterproductive, for example output power dropping for each amplifier if 5 were in use vs 3, even if the extra two weren't very demanding. That does not seem to be the case. So given that, it's free (I was already wired from previous trials and I have amp outputs available) so why not. What you get theoretically is the more *demanding* half-speaker going through a separate amp and separate wire from the more *sensitive* half-speaker, which seems like a good idea. What you don't get is a doubling of the power; you get the sum of the demands of the two half-speakers, but one of them is going to be the limitation and you know which one. So unless the loads on each happen to be identical, it's less than a doubling. If you need double the power, you want the larger amp not the bi-amping. Thanks -- I've considered it, and the r600c wich is supposedly the exact match for the r300, but they are both bulky, visually overbearing, and I'm wary of how that rear port will behave in my cabinet. My current plan is actually to use a single Q100 on its side -- cheap, same size UniQ and front vented, the R300's can take care of the bass, and I get to keep much more of my cabinet. It won't be the same quality as the R300's, but then again it won't need to be there for music duties. |
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Post by fusioneer on Nov 22, 2014 12:59:40 GMT -5
unsound: forgot to answer the question on volume: the volume milestones aren't any different, nor do I expect them to. This is because volume controls voltage, not power.
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Post by unsound on Dec 1, 2014 13:21:32 GMT -5
fusioneer: what you say does make sense. That is, the per channel ceiling is raised. Since the tweeter and woofer do require different amounts of power, I wouldn't expect the output to double. In my case, the 201/2s are 3-way speakers and I've bi-wired them with the tweeter/mid getting 1 channel and the woofer getting the other. This split would be a little bit more balanced in terms of power needs than in a 2-way speaker. Can't say that I've noticed any difference, though. But, I'm gonna leave them that way for now. I'll have to think about the "volume controls voltage, not power". Yes, volume does control voltage, but doesn't that control power? The only way to change power output from the speaker is by increasing the volume, is it not?
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Post by fusioneer on Dec 1, 2014 14:24:01 GMT -5
unsound: my R300's are similar, three way with two sets of binding posts, one for the woofer and one for the Uni-Q combo. For their crossover at 500hz I found in a table online that I can expect 60%/40% power requirements, so I'm fairly close to doubling the power. It gets the Fusion above the power handling of the R300's (if I were to test max volume), so I'm all set. Re: voltage. All other things equal, voltage controls power. But here all other things are NOT equal: with bi-amping I've increased the impedance presented to each amplifier, so at the same level each spends less power for the same total output. From the half-speaker's perspective, it sees the same voltage at the same level, and it responds with the same db output (at least before amplifier limits in either scenario). Just like it would if the two wiring terminals were connected together -- same voltage. Which is why I don't expect to see higher volume.
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Post by unsound on Dec 1, 2014 15:22:29 GMT -5
unsound: my R300's are similar, three way with two sets of binding posts, one for the woofer and one for the Uni-Q combo. For their crossover at 500hz I found in a table online that I can expect 60%/40% power requirements, so I'm fairly close to doubling the power. It gets the Fusion above the power handling of the R300's (if I were to test max volume), so I'm all set. Re: voltage. All other things equal, voltage controls power. But here all other things are NOT equal: with bi-amping I've increased the impedance presented to each amplifier, so at the same level each spends less power for the same total output. From the half-speaker's perspective, it sees the same voltage at the same level, and it responds with the same db output (at least before amplifier limits in either scenario). Just like it would if the two wiring terminals were connected together -- same voltage. Which is why I don't expect to see higher volume. I think the 201/2 is at 400hz for the woofer crossover, but I'm not a 100% sure. That makes sense, thanks! |
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Post by fusioneer on Dec 1, 2014 22:05:26 GMT -5
OMG OMG OMG! I am giddy as a school girl! The replacement Fusion just got here and all my problems are fixed! This is unbelievable! This means: * no pops, even when I work the mute button, let alone DVR operations. Just dead silent like unsound reported. * sync after audio stream interruption is much faster! Most of the time, there is no interruption at all and sound starts just as the image starts moving. Sometimes, it takes a couple of seconds but a small minority of the time. * HDMI switching is near instant! I'm talking sub-second, like I knew the Fusion could but for some reason it started flailing with the Chromecast. Not anymore! Woohoo! This is awesome. Now this doesn't mean all problems, just the ones that I couldn't get around. If I run the cable box via HDMI only I still get the screech when switching from SD to HD, but since running the sound through optical is pretty much perfect, I don't care. And I haven't tested the headphone issue yet, but whatever. Not to mention, because the package was a little later than I expected and I didn't want to beg Amazon for a few MORE days of return, I had a chance to spend a few days with the Denon again, and once again I notice the immense difference. It's criminal that they're able to sell this at a higher price than the Fusion. I will update my reviews here and on Amazon, most likely to 5 stars, when I get some time tomorrow (because I don't want to do a hack job). Thanks again unsound! I'm not sure if my original unit was defective or firmware .54 is Da Bomb, but the combination makes me very happy!! |
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Post by unsound on Dec 2, 2014 1:45:22 GMT -5
Glad it worked out for you fusioneer. I got my sister a used unit from a lounge member. I'm assuming that's a .51. I will check it out next week to see if I notice any differences between it and my unit. All I got from her was that it sounds much better than the Yamaha it replaced. We do need to find out from Emo what they changed and how to upgrade the firmware. I'm on the road for the next 10 days so I'm hoping someone else will find out. |
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