Proper max output voltage setting

[john_w]

I'm working my way through the settings on a new Hifi Rose RS150B and I'm a little confused while trying to match the Rose's analog output voltage (adjustable) to the max input voltage on my Yamaha A-S2200 (integrated amp) balanced input. The spec from Yamaha reads like this: Input Sensitivity - [1 kHz, 100 W/8 ohms] PHONO MC: 150 uVrms/50 ohms, PHONO MM: 3.5 mVrms/47 kohms, CD, etc.: 200 mVrms/47 kohms, MAIN IN: 1 Vrms/47 kohms, BAL: 200 mVrms/100 kohms. The way I understand this information, the Yamaha wants 200 mVrms at its balanced input, but will handle 1Vrms at its unbalanced input. Is this correct? Can someone explain the gap in the two voltages?

Adding to my confusion, I looked up the spec on the Yamaha CD-S2100 which is intended to pair with my AS2200 thinking I could just set the Rose at the CD player's output voltage. The spec for the CD player's output level reads: 2 +/- 0.3 V (1 kHz, 0 dB). So if I'm reading that right, Yamaha's own CD player outputs twice the voltage wanted by the AS2200? There's no distinction for balanced/unbalanced in the CD player specs.

The Rose can output up to 9Vrms at XLR.

Hoping to better understand this.

 

[DVDdoug]

The integrated amplifier has a volume control but if you turn the volume all the way up you should be able to get full power with 200mV into the balanced input, etc. Less than that and you won't get the full 100W with 200mV in.

Line Level is rather loosely defined but most outputs have more than enough signal and most inputs have more than enough sensitivity so that everything works together.

 

[antcollinet]

Your amp has component inputs (Phono, CD etc) with input sensitivity as specified. It also has a Main In (if you want to use it as a power amp driven by a device with it's own volume control. Input sensitivity on Main is 1V

So are you going to control volume on the RS150, then go into the main terminals with 1V sensitivity - or use the amp as volume control, then go into one of the line inputs (I'd suggest balanced) with the 200mV sensitivity. In this case I'd set the balanced output from the rose to something MUCH lower than 9V

 

[john_w]

Your amp has component inputs (Phono, CD etc) with input sensitivity as specified. It also has a Main In (if you want to use it as a power amp driven by a device with it's own volume control. Input sensitivity on Main is 1V

Ah, that clears that up.

So are you going to control volume on the RS150, then go into the main terminals with 1V sensitivity - or use the amp as volume control, then go into one of the line inputs (I'd suggest balanced) with the 200mV sensitivity. In this case I'd set the balanced output from the rose to something MUCH lower than 9V

Yes, the Rose analog outputs are set to fixed and software volume control is turned off. Yamaha is handling the preamp duties. Rose is connected to Yamaha via XLR. Brings a few more questions:

Is input sensitivity the minimum voltage the preamp needs to see?
Will I benefit from a higher output voltage than 200mV from the Rose - more punch or detail?
Will increasing the Rose's output voltage introduce noise?

 

[antcollinet]

Input sensitivity (as stated by @DVDdoug above) is the input voltage the amp needs to output rated (full) power with the volume at max.

So when your music is at its loudest (eg Creshendos - or just continually loud/noisy stuff) then if your streamer is putting out 200mV, then you'll be able to drive the amp to full power.

If you put out more than 200mV and the amp volume is at full, then the amp will be clipping.

However, I'd probably sett the RS150 to put out a little higher than 200mV so you have a bit of headroom - say 300mV. Then just don't go up to full volume on the amp. You won't get better punch from a higher voltage - you might get better SNR, since the amp won't be ampifying the input signal so much. You'll only hit problems with higher input voltage from restricting the range on your volume control on the amp - or if you hit an input voltage limit and the input clips. Specs allow up to 2.8V input, so you shouldn't have any worries up to that level.

If you can't set it that low then don't worry about it - just don't turn the amp volume up as much. You probably won't want to be going anywhere near that high anyway.


EDIT - just noticed that you have a 6dB attenuation option on the balanced input. I'd probably use that, and double the input voltage.

 

[john_w]

If you can't set it that low then don't worry about it - just don't turn the amp volume up as much. You probably won't want to be going anywhere near that high anyway..

The Rose allows settings from 100mV to 9000mV. I've been listening at 200mV but will give 300 a shot.

EDIT - just noticed that you have a 6dB attenuation option on the balanced input. I'd probably use that, and double the input voltage.

What's the thinking here?

 

[AnalogSteph]

The good thing about having overkill gear is that you have a substantial amount of leeway.

The streamer sports an AK4499 based DAC, which strongly suggests that it should be preamp grade. If sufficiently convenient, make use of its volume control and run it into the Yamaha's MAIN IN.

If you do insist on using it as a plain old line-level DAC (even if it's kind of a waste), 0 dBFS level should be set higher than just 200-300 mV. I would suggest 2000 mV when using volume normalization features and/or EQ (or a majority of orchestral classical music) and either 1000 or 500 mV when not doing so. Double these values when using balanced in with -6 dB attenuation. This should give good signal levels while leaving at least 3 dB worth of headroom at al times, usually more.

What's the thinking here?

It gives a more robust signal level, though I bet in this case the main point may have been compensating for the 6 dB gain commonly found in balanced output stages, so the balanced input doesn't stand out among unbalanced sources.

It is unclear to me at this point whether the A-S2200 has a traditional analog volume pot or merely uses one to control a PGA - it wouldn't surprise me if it were the latter, in which case channel tracking at low levels would be a non-issue. If there is no sign of channel imbalance or touchiness below about 9 o'clock, you can up the 1000 or 500 mV to 2000 mV easily.

 

[antcollinet]

The Rose allows settings from 100mV to 9000mV. I've been listening at 200mV but will give 300 a shot.View attachment 230743

What's the thinking here?

My thinking was optimising SNR. An element of the noise on the output of the streamer will be independent of output level. So by upping the output level you are improving the SNR on the output. Further any noise on the interconnect - or inherrent in the inputs will also be attenuated.

Probably inaudible difference though.

 

[john_w]

The streamer sports an AK4499 based DAC, which strongly suggests that it should be preamp grade. If sufficiently convenient, make use of its volume control and run it into the Yamaha's MAIN IN.

My Rose is the B variant and uses an ESS chip now. I’ve turned off the Rose volume control because I use the Yamaha phono stage and also run my Linn CD player directly through the Yamaha - it’s an older model with no digital outs. But I understand your point and I was under the impression that defeating something digital in my signal path might reduce noise to some degree.

If you do insist on using it as a plain old line-level DAC (even if it's kind of a waste), 0 dBFS level should be set higher than just 200-300 mV. I would suggest 2000 mV when using volume normalization features and/or EQ (or a majority of orchestral classical music) and either 1000 or 500 mV when not doing so. Double these values when using balanced in with -6 dB attenuation. This should give good signal levels while leaving at least 3 dB worth of headroom at al times, usually more.

I’ll give this a try.

It is unclear to me at this point whether the A-S2200 has a traditional analog volume pot or merely uses one to control a PGA - it wouldn't surprise me if it were the latter, in which case channel tracking at low levels would be a non-issue. If there is no sign of channel imbalance or touchiness below about 9 o'clock, you can up the 1000 or 500 mV to 2000 mV easily.

The Yamaha is a 100% analog device as I understand it.

 

[john_w]

My thinking was optimising SNR. An element of the noise on the output of the streamer will be independent of output level. So by upping the output level you are improving the SNR on the output. Further any noise on the interconnect - or inherrent in the inputs will also be attenuated.

Probably inaudible difference though.

Understood. Worth trying.

 

[john_w]

Did some listening last night to compare 2000mV (-6db setting on) vs 500mV (-6db setting off) vs 200mV (-6db setting off).

I heard no difference, other than volume, between 200 and 500. 2000mV sounded best to me. Most noticeably the soundstage seemed to have more depth. Some subtle sounds seemed more apparent, but I was estimating similar volumes when switching between voltages. At any rate, sounds great at 2000mV and I appreciate the help and info.

 

[restorer-john]

It is unclear to me at this point whether the A-S2200 has a traditional analog volume pot or merely uses one to control a PGA - it wouldn't surprise me if it were the latter

A-S2100:

All the Yamaha amplifiers below the A-S2200 also use an input selector IC which cannot take much more than 2200-2400mV before overloading, so winding back the DAC output level to under that would be good idea. Not sure of the actual implementation in the 2200, but it's unlikely to be massively different to the 301/501/701/1100 etc

Edit: looking at the A-S2100 S/M.

The A-S2100 (previous model) schematic is a mess. God I miss proper schematics. Gives me a headache. A 1980s Sony schematic is a joy to look at.

Here's the Japanese doing what they do best overcomplicating a simple task. An input selector resistor array read by an A/D with window values, processed to drive the electronic switching of the correct input.

Yamaha took it to a similar level of stupidity in the early 90s with a micro driven, motorized rotary input selector operable by remote. What a reliability nightmare they were too. No fun to repair either.