Emotiva lists 1.0V as the standard output for the XSP-1, however, the distortion is actually spec'd at 2.0V. No other voltages are listed. I was reassured by Emotiva that "6 Volts" is the maximum, but I wasn't entirely clear on whether this was input or output, and I'm concerned about the 3.8V or so from the singled ended output of my DVD-9000 playing HDCD's.
I've measured the maximum voltages now, somewhat approximately because I'm only using "instrumentation loads" like my 10M DVM and 1M oscilloscope. This is a factor that 10 years ago and before I simply ignored.
Anyway, for single ended I/O the maximum input is very impressive at 9.6V RMS (measured with the gain at -20dB). Maximum SE output is around 6.8V (gain at +12.0) at onset of obvious clipping, a tad bit of obtuse rounding can be seen above 5.5V (looking on my newest digital oscilloscope).
Driving the output into very hard clipping close to 10V can cause square wave doubling. This is an undesireable per se, but in most circumstances your home amplifier will already have exploded at 10V sine wave input. This is not an instability, what happens is that after the top of the sine wave flattens, the center begins to grow negatively proportional to further drive, until this center downward spike reaches the bottom, making the clipping wave, now pretty much square, into a doubled square wave at twice the original frequency. It shows essentially that multiple internal elements are clipping at not exactly the same time...therefore something like a push pull output.
True pro equipment can handle 10V as a standard level. That's probably why Emotive lists the standard level as 1V, to make it clear it's not 10V pro gear--which is compromised in S/N at lower consumer levels.
These I will not be pushing the Emotiva limits in any way, though a recent adjustment to the Lavry was to set max level (-8dB) to -17dBU which is 5.4V, which would be a touch too high for single ended output on the Emotiva, but probably gives around 6dB headroom for balanced output (not measured yet, that presents some challenges).
Certainly the input will handle anything I can throw at it input wise.
On my Juli@ card, using RMAA, with balanced I/O last weekend I measured about 0.0005% or 0.0006%, with my residual at 0.0003%, meaning the actual distortion is around 0.0003%, as shown in website graphics (showing better than the claimed spec of 0.0005). These are measured at the 4V input level of the card, minus about 0.9dB. I measure this either to 96kHz sampling or 44.1kHz sampling with the same result, showing no super high harmonics, very clean top end. Basically my residual and the Emotive line up perfectly, save a little more 3rd harmonic (the push-pull output cancelling any 2nd order distortion) and down below -120dB a tiny bit of 7th (generally, stuff below -110dB can be ignored, the Denon DVD-9000 is full of high frequency hash at -115dB but is one of the best sounding CD players I've ever heard). It was this cleanness that sold me on the Emotiva, among other things, and having the best phono circuit in my collection clinched it as my living room analog preamp, requiring me to get a second for the bedroom I had originally purchased my first unit for several years ago. The THD levels compare favorably with the BEST current Mark Levinson at $40k, and the Emotiva has the essential-for-me digital volume control if not as nicely implemented as the Levinson.
On my Sound Technology, I get measurements showing that single ended output should be kept below 4V. (I actually don't use the single ended output for anything except driving the Sonos box at 2V in the bedroom. The balanced outputs go to the Masterlink in the bedroom, and the Lavry in the Living Room, my two most critical things.)
6V output...4% THD
5V output...0.38% THD
4V output...0.0063% THD
3V output...0.0046% THD (this is about my residual on this analyzer when it's working great, once in a blue moon it can hit 0.0044%, but right after taking these measurements it decided to go beyond 3% resdual, a sign of internal overwarming or something, so I shut it down).
In balanced output, this would probably translate to a maximum low distortion output of 8V, well more than what I need for the Masterlink (4V) or the Lavry (5.4V). Right now, with cranky Sound Technology analyzer, I can't do the measurement I had hoped to do this afternoon to confirm that.
Bless the Sound Technology, after 3 hours rest it came back on and I was able to record a better residual, which is I think not untypical actually (until after a few hours, it will go up, I adjusted my ST that way so I could do decent measurements without 3 hours warmup, I'm usually just doing a few measurements, though this way, in 3 hours you can't use it optimally). That is:
Sound Technology Residual: 0.0033% THD
Keep those in mind for the above measurments, the 3V Emotiva output is not exactly the residual, it's 0.0013% higher, but that might depend on the number of minutes of warm up also not that much. Actually I know from other measurements 2V is at 0.0003%, so the 0.0013% probably says more about the ST and it's state of warmup (remember, it failed just a few minutes later, and I had to let it cool down for 3 hours).
Anyway, with some problematic adapters they may have been contributing, I measured output distortion balanced, once again using the ST as primary source.
At 8V balanced, distortion was a hair above the residual at 0.0038%.
At 10V, distortion had risen to 0.03%.
At 9V, distorition was also around 0.03%
So my prediction about 8V being the highest low distortion output level seems correct, the peak optimal RMS levels are:
4V single ended
8V Balanced
At these output levels, THD has not increased since the lowest output levels, and may even have reached its lowest level.
It goes higher, but distortion starts rising, fwiw, still way below speakers and such a few dB higher. I'd keep it below 6V single ended and 12V balanced in all cases with great prejudice, though it doesn't really break up till even higher.
I could even crank up the input level on the Lavry, now set to 5.4V, a few dB higher.
I've measured the maximum voltages now, somewhat approximately because I'm only using "instrumentation loads" like my 10M DVM and 1M oscilloscope. This is a factor that 10 years ago and before I simply ignored.
Anyway, for single ended I/O the maximum input is very impressive at 9.6V RMS (measured with the gain at -20dB). Maximum SE output is around 6.8V (gain at +12.0) at onset of obvious clipping, a tad bit of obtuse rounding can be seen above 5.5V (looking on my newest digital oscilloscope).
Driving the output into very hard clipping close to 10V can cause square wave doubling. This is an undesireable per se, but in most circumstances your home amplifier will already have exploded at 10V sine wave input. This is not an instability, what happens is that after the top of the sine wave flattens, the center begins to grow negatively proportional to further drive, until this center downward spike reaches the bottom, making the clipping wave, now pretty much square, into a doubled square wave at twice the original frequency. It shows essentially that multiple internal elements are clipping at not exactly the same time...therefore something like a push pull output.
True pro equipment can handle 10V as a standard level. That's probably why Emotive lists the standard level as 1V, to make it clear it's not 10V pro gear--which is compromised in S/N at lower consumer levels.
These I will not be pushing the Emotiva limits in any way, though a recent adjustment to the Lavry was to set max level (-8dB) to -17dBU which is 5.4V, which would be a touch too high for single ended output on the Emotiva, but probably gives around 6dB headroom for balanced output (not measured yet, that presents some challenges).
Certainly the input will handle anything I can throw at it input wise.
On my Juli@ card, using RMAA, with balanced I/O last weekend I measured about 0.0005% or 0.0006%, with my residual at 0.0003%, meaning the actual distortion is around 0.0003%, as shown in website graphics (showing better than the claimed spec of 0.0005). These are measured at the 4V input level of the card, minus about 0.9dB. I measure this either to 96kHz sampling or 44.1kHz sampling with the same result, showing no super high harmonics, very clean top end. Basically my residual and the Emotive line up perfectly, save a little more 3rd harmonic (the push-pull output cancelling any 2nd order distortion) and down below -120dB a tiny bit of 7th (generally, stuff below -110dB can be ignored, the Denon DVD-9000 is full of high frequency hash at -115dB but is one of the best sounding CD players I've ever heard). It was this cleanness that sold me on the Emotiva, among other things, and having the best phono circuit in my collection clinched it as my living room analog preamp, requiring me to get a second for the bedroom I had originally purchased my first unit for several years ago. The THD levels compare favorably with the BEST current Mark Levinson at $40k, and the Emotiva has the essential-for-me digital volume control if not as nicely implemented as the Levinson.
On my Sound Technology, I get measurements showing that single ended output should be kept below 4V. (I actually don't use the single ended output for anything except driving the Sonos box at 2V in the bedroom. The balanced outputs go to the Masterlink in the bedroom, and the Lavry in the Living Room, my two most critical things.)
6V output...4% THD
5V output...0.38% THD
4V output...0.0063% THD
3V output...0.0046% THD (this is about my residual on this analyzer when it's working great, once in a blue moon it can hit 0.0044%, but right after taking these measurements it decided to go beyond 3% resdual, a sign of internal overwarming or something, so I shut it down).
In balanced output, this would probably translate to a maximum low distortion output of 8V, well more than what I need for the Masterlink (4V) or the Lavry (5.4V). Right now, with cranky Sound Technology analyzer, I can't do the measurement I had hoped to do this afternoon to confirm that.
Bless the Sound Technology, after 3 hours rest it came back on and I was able to record a better residual, which is I think not untypical actually (until after a few hours, it will go up, I adjusted my ST that way so I could do decent measurements without 3 hours warmup, I'm usually just doing a few measurements, though this way, in 3 hours you can't use it optimally). That is:
Sound Technology Residual: 0.0033% THD
Keep those in mind for the above measurments, the 3V Emotiva output is not exactly the residual, it's 0.0013% higher, but that might depend on the number of minutes of warm up also not that much. Actually I know from other measurements 2V is at 0.0003%, so the 0.0013% probably says more about the ST and it's state of warmup (remember, it failed just a few minutes later, and I had to let it cool down for 3 hours).
Anyway, with some problematic adapters they may have been contributing, I measured output distortion balanced, once again using the ST as primary source.
At 8V balanced, distortion was a hair above the residual at 0.0038%.
At 10V, distortion had risen to 0.03%.
At 9V, distorition was also around 0.03%
So my prediction about 8V being the highest low distortion output level seems correct, the peak optimal RMS levels are:
4V single ended
8V Balanced
At these output levels, THD has not increased since the lowest output levels, and may even have reached its lowest level.
It goes higher, but distortion starts rising, fwiw, still way below speakers and such a few dB higher. I'd keep it below 6V single ended and 12V balanced in all cases with great prejudice, though it doesn't really break up till even higher.
I could even crank up the input level on the Lavry, now set to 5.4V, a few dB higher.
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