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Dac + amp Probably a simple question

Thanks for all the info.

Very nice feedback and option, seems to be a very wise choice.

Also has rca and xlr versions for both minidsp and amp.

A question according to the review it shows power 190 watts and at 235 reaches 1% thd. Would a little headroom be better for the 250w speakers?

Thank you.

Best regards
What do you think "250w" speakers means particularly? Your listening levels, distance from the speakers and speaker sensitivity has a lot more to do with it....
 
I guess a raspberry pi with volumio is the way connected via USB to minidsp device?
It's certainly a way. The home brew approach doesn't suit everyone though. And so far, I've not found a Pi based system with the usability of (eg) a wiim mini.
 
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What do you think "250w" speakers means particularly? Your listening levels, distance from the speakers and speaker sensitivity has a lot more to do with it....
Well the KEF R11 Meta Tower says 250 watts has 5 drivers on a tower so it's really like 50 watt per driver they run below 1%THD excluding area below 80hz, so my math was if the amp only goes to 215 below 1% thd then I would be introducing thd into the drivers if played at full volume With the AUDIOPHONICS MPA-S250NC RCA/xlr that's why I mentioned headroom.

Or am I wrong?
 
It's certainly a way. The home brew approach doesn't suit everyone though. And so far, I've not found a Pi based system with the usability of (eg) a wiim mini.
My biggest question is would the pi introduce noise? I mean it shouldn't since it going by usb straight to minidsp right? Then it gets converted to analog to send to the amp, even minidsp uses this in their SHD units
 
Well the KEF R11 Meta Tower says 250 watts has 5 drivers on a tower so it's really like 50 watt per driver they run below 1%THD excluding area below 80hz, so my math was if the amp only goes to 215 below 1% thd then I would be introducing thd into the drivers if played at full volume With the AUDIOPHONICS MPA-S250NC RCA/xlr that's why I mentioned headroom.

Or am I wrong?
Wrong. The math you provided is meaningless as to how things actually work to the driver/wattage thing. Try using an spl calculator like this perhaps to get a better idea of needs http://www.hometheaterengineering.com/splcalculator.html
 
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My biggest question is would the pi introduce noise?
No reason it should any more than any other digital streaming device.
 
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Wrong. The math you provided is meaningless as to how things actually work to the driver/wattage thing. Try using an spl calculator like this perhaps to get a better idea of needs http://www.hometheaterengineering.com/splcalculator.html
I mean I wasn't talking about actual spl but could you explain me the driver/wattage thing, 2 reasons, one kef website actual says speaker use 15 to 300 watts I suppose that value is wrms, and I heard amps should be a little above speakers so they aren't strained, so kef r11 Meta has 5 drivers and can go up to 300 wrms, so with a 250wrms amp they certainly won't get to 100% possible spl. I'm not saying I need the towers at 300 wrms playing, since even at 40 wrms that gives a spl of 117 db using the site you posted, which would likely make my ears bleed as I don't like LOUD music. But I do love clean 0distortion music. Just trying to learn here.
 
I mean I wasn't talking about actual spl but could you explain me the driver/wattage thing, 2 reasons, one kef website actual says speaker use 15 to 300 watts I suppose that value is wrms, and I heard amps should be a little above speakers so they aren't strained, so kef r11 Meta has 5 drivers and can go up to 300 wrms, so with a 250wrms amp they certainly won't get to 100% possible spl. I'm not saying I need the towers at 300 wrms playing, since even at 40 wrms that gives a spl of 117 db using the site you posted, which would likely make my ears bleed as I don't like LOUD music. But I do love clean 0distortion music. Just trying to learn here.
Generally the max wattage rating is just where you might expect damage and not particularly great quality output. KEF isn't quite honest, it can use less than one watt easily enough. It's just a suggested range of amp power (and notice no particular specific amp spec). Generally the upper limit is more a damage limit than a useful sound quality output, but distance comes into play so you need to calculate for distance from speaker too. 117dB is very very loud (and few speakers do that well). Theater spec for a movie is a peak of 115dB (at your seat for LFE channel, 105 for other channels) from a single speaker....maybe you need to use even a simple phone spl meter app to see what your general spl requirements are, but probably far less.

ps Individual drivers and how connected with passive crossovers is a more complex discussion as to how wattage/impedance/etc works
 
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I'm sure 80db is already somewhere around the max I'd listen to anything. Might be wrong . But thanks for all the feedback. I don't like how movies (cinema) is so loud.
 
I'm sure 80db is already somewhere around the max I'd listen to anything. Might be wrong . But thanks for all the feedback. I don't like how movies (cinema) is so loud.
Full movie reference volume in a small room can be bad, especially if the room hasn't been optimized for such. Many don't listen that loud. Thus affects your amp needs. While it's great to have a big hunky amp that can handle pretty much anything you need, that doesn't work for everyone but these days they are relatively cheap.
 
Any suggestions for an active sub to pair with kef r11 Meta Tower ?

My bad I meant sub not amp
 
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Any suggestions for an active amp to pair with kef r11 Meta Tower ?
Hypex Nilai based, or Purify based.

Both have audibly perfect sound quality, oodles of power, and reasonable cost.
 
What makes those "active" amps particularly?
Nothing. I was answering the question he wants answering without worrying about his misunderstanding about "active" You already had that covered. :p
 
Nothing. I was answering the question he wants answering without worrying about his misunderstanding about "active" You already had that covered. :p
Thought I missed something :)
 
I meant sub, so what's the proper word for a self powered sub
Usually called just a sub these days as there are almost no passive versions (outside of diy). Powered or active sub works, tho.
 
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I meant sub, so what's the proper word for a self powered sub
Two terms are used for speakers with built in amps.

Powered - normally a speaker with a single amp, and traditional crossover. (Made from passive resistors, capacitors and inductors)
Active - normally a speaker with one amp per driver, and active (DSP based) crossovers.

A sub having normally only one driver is normally a powered sub, but as pointed out by @Chrispy the "powered" part of that is pretty much redundant.

However, some subs have active crossovers which do the work of crossover between sub and main spakers - these could reasonably be called active subs - though I've never actually seen that term used with that context.


However these distinctions are not universally understood, and the term acitve and powered are often used interchangeably.


Separate amps are not described as active.
 
But with mini dsp I should avoid subs with passive crossovers no?
 
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