[Ripper2860]

Yeah -- I'm not 100% sure that's correct. Could be, but not knowing the design how do we know there is not an additional amplification/gain stage to get a HIGH GAIN output? Given that the specs on Magni 3, for example, specifies a higher distortion at High Gain vs Low Gain, could certainly indciate the introduction of a 2nd gain stage over the Low Gain setting. Sure Low Gain could also be a resistor/load type of circuit applied to a single GAIN stage, but do we REALLY know that, or are we speculating? The fact that there are varying levels of feedback between LOW (more feedback) and HIGH (less feedback) seems to indicate to me that far more than a switched resistor circuit in play.

Maybe I'm a dumbass, and I'm certainly not an audio engineer, so I'm willing to say that I don't know if High Gain is a boosted Low Gain, or if Low Gain is a throttled High Gain. I also don't think @Jason Stoddard has ever really discussed the specifics of his LOW/HIGH GAIN design.

BTW -- I contacted Schiit support regarding the their implementation of LOW and HIGH Gain several months ago and never got an answer.


PS -- In the end, does it really matter? Just go with whatever sounds best to you and drown out that nagging 'You must know' voice in your head with some nice Jazz music. It'll eventually give-up and go away -- if only for a while ...

 

[FrivolsListener]

?

Yeah, this has become a, "identify the engineers" test.

Guys, one of the reasons you put an amplifier in your system is to provide gain. High gain means more gain, low gain means less gain, but they're both providing gain.

(Yeah, there's impedance matching and a bunch'a other reasons, too, but let's keep it simple.)

 

[Paladin79]

It is sometimes difficult to answer a question because of how it is asked but Frivolis is correct. Now which headphones sound better at high gain and which at low, I cannot say without looking at amplifier specs about voltage and current and impedance. If high gain has more voltage then it would be the 300 ohm and above headphones. Low impedance work with high current as I recall.

 

[wingsounds13]

The flaw in thinking is equating gain with power. There is no relationship between the two. Gain is ONLY the ratio of output voltage to input voltage. Higher gain means only that the maximum output voltage will be achieved with a lower input signal level.

J.P.

 

[Paladin79]

Well said

 

[jimmers]

... If high gain has more voltage then it would be the 300 ohm and above headphones. Low impedance work with high current as I recall.

I always bite on this

Given the same efficiency (dB/mW) then this is so,

However:
looking at 3 of my phones, according to Innerfidelity's measurements, sensitivity, voltage for 90dB.
HD650 (320 Ohm) 0.205V
AKG Q701 (64 Ohm) 0.301V
Massdrop HiFiMAN HE4XX (40 Ohm) 0.271V

So these lower impedance phones, one dynamic, one planar need more voltage, and hence much more current, than the higher impedance phone for the same output level.

Pardon my pedantry

 

[Ripper2860]

The flaw in thinking is equating gain with power. There is no relationship between the two. Gain is ONLY the ratio of output voltage to input voltage. Higher gain means only that the maximum output voltage will be achieved with a lower input signal level.

Agreed. Some are equating GAIN with impedance/load, voltage, and current like somehow GAIN performs adjustments to drive different headphone loads. Some folks seem to be confused thinking that a GAIN switch is like a capacitance and load switch on a phono preamp designed to accommodate different capacitance and resistance loads. Gain is defined in the audio world as an increase in voltage between a circuit's input and output. A pure GAIN increase results in only a voltage change as I see it. (But again, I'm no EE.)

Now does Schitt's LOW GAIN/HIGH GAIN setting do more than a pure GAIN circuit?

 

[ItsAllInMyHead]

With all this talk of high gain vs low gain, can someone answer my noobish question.

Schiits website advises the following for my Magni 3. "MaximumPower, 300 ohms: 430mW RMS per channel"

Is that on low gain or high gain? Or does power have nothing to do with gain?

Tom and others provide technically correct answers, but I am not sure if it's what you're looking for. I had a similar question awhile ago while I was trying to understand some basics of what happens inside typical headphone "amps" vs. loudspeaker amps and I think I learned... In most headphone "amps" - there's an amplification component and a volume control component in its most simplistic description.

I am going waaaaaaay out on a limb here, since I am no expert. I'm also willing to remove or correct below and show my ignorance to the world, but that's how I learn.

tl;dr version - The maximum power output at a given impedance is independent of the gain of the amp. Your Magni 3 can still put out the max power at the low gain, but it would take a larger input voltage to reach the maximum output voltage (all things remaining equal, which they rarely are).

Long version -

With the Magni 3 you have the choice of 2 or 7 for gain. Gain is essentially the voltage multiplier for the amp. 1V in at gain of 7 = 7V out. 1V in at gain of 2 = 2V .... within the amp stage. Not within the "box" .. i.e. if there was no volume control knob.

In essence with the Magni 3, you'd need 3.5 times the "input voltage" with a gain of 2 to achieve the same output voltage at a gain of 7. In a hypothetical...

0.43W 300Ohms => 11.3578167V 0.037859389A

So... the Magni taps out at about 11ish Volts with a 300 Ohm load.

With gain of 2 - the input voltage to get to max 11V is 5.5V Anything above that input voltage at that gain, and the amp clips the signal to the max output of 11V.
With a gain of 7 - the input voltage to get to 11V is 1.57V

Imagine a Magni 3 as a pure amp only with no volume knob. Let's call it a Magni NV. Let's pair it with a Modi 2 (fixed output voltage of 1.5V) It'd be sitting there pushing out either 3 or 10.5 Volts depending on the gain you chose. If you supplied it 5.5 volts from some other device at the same gain of 2, it'd sit there and happily hum along at the same 11V output. If you switched it to the gain of 7, it'd be pissed at you, still only output 11V, and clip the signal. If you swapped your input to a Modi MB with a 2V output - you'd get 4V and 11V (clipped) with the gain settings of 2 and 7 respectively.

This is related, but separate to the voltage needed to drive a particular speaker across a range of pleasing volumes (or the linearity of an analog volume pots and adjusting gain to a nice operating range) etc. etc.

**All of this assumes that we don't operate in the real-world, that amps function perfectly linearly at all voltage input ranges across all frequencies etc. etc. etc. Since output impedance for the amps we're using is very low and because of the types of drivers we're using in our headphones (not electrostatics), you can essentially think of a perfect amp in an ideal world as a perfectly linear voltage amplifier vs. a current source. Caveat emptor, YMMV, IMHO, I'm an idiot... etc. etc.

 

[wingsounds13]

@ItsAllInMyHead You took the long way to say it, but you have it exactly right. This can be confusing, but ultimately not that hard to understand if you understand a few basic concepts. Separating these concepts seems to be the biggest challenge until you understand at least some of them. Voltage gain, maximum output voltage, maximum output current, open loop impedance, closed loop impedance, clipping, volume control,... That's just a short list. No wonder people get confused.

My head is beginning to hurt and I already understand much of this stuff.

J.P.

 

[Rensek]

Tom and others provide technically correct answers, but I am not sure if it's what you're looking for. I had a similar question awhile ago while I was trying to understand some basics of what happens inside typical headphone "amps" vs. loudspeaker amps and I think I learned... In most headphone "amps" - there's an amplification component and a volume control component in it's most simplistic description.

I am going waaaaaaay out on a limb here, since I am no expert. I'm also willing to remove or correct below and show my ignorance to the world, but that's how I learn.

tl;dr version - The maximum power output at a given impedance is independent of the gain of the amp. Your Magni 3 can still put out the max power at the low gain, but it would take a larger input voltage to reach the maximum output voltage (all things remaining equal, which they rarely are).

Long version -

With the Magni 3 you have the choice of 2 or 7 for gain. Gain is essentially the voltage multiplier for the amp. 1V in at gain of 7 = 7V out. 1V in at gain of 2 = 2V .... within the amp stage. Not within the "box" .. i.e. if there was no volume control knob.

In essence with the Magni 3, you'd need 3.5 times the "input voltage" with a gain of 2 to achieve the same output voltage at a gain of 7. In a hypothetical...

0.43W 300Ohms => 11.3578167V 0.037859389A

So... the Magni taps out at about 11ish Volts with a 300 Ohm load.

With gain of 2 - the input voltage to get to max 11V is 5.5V Anything above that input voltage at that gain, and the amp clips the signal to the max output of 11V.
With a gain of 7 - the input voltage to get to 11V is 1.57V

Imagine a Magni 3 as a pure amp only with no volume knob. Let's call it a Magni NV. Let's pair it with a Modi 2 (fixed output voltage of 1.5V) It'd be sitting there pushing out either 3 or 10.5 Volts depending on the gain you chose. If you supplied it 5.5 volts from some other device at the same gain of 2, it'd sit there and happily hum along at the same 11V output. If you switched it to the gain of 7, it'd be pissed at you, still only output 11V, and clip the signal. If you swapped your input to a Modi MB with a 2V output - you'd get 4V and 11V (clipped) with the gain settings of 2 and 7 respectively.

This is related, but separate to the voltage needed to drive a particular speaker across a range of pleasing volumes (or the linearity of an analog volume pots and adjusting gain to a nice operating range) etc. etc.

**All of this assumes that we don't operate in the real-world, that amps function perfectly linearly at all voltage input ranges across all frequencies etc. etc. etc. Since output impedance for the amps we're using is very low and because of the types of drivers we're using in our headphones (not electrostatics), you can essentially think of a perfect amp in an ideal world as a perfectly linear voltage amplifier vs. a current source. Caveat emptor, YMMV, IMHO, I'm an idiot... etc. etc.

Thanks to all for the knowledge. I think this last one gave me some welcome insight into the synergy of my Chromecast/Mimby/Magni3 path. I have long believed that the mini toslink output on my Chromecast Audio is inserting extra gain into my Mimby, which is then adding that same extra gain into my Magni 3. When I use the Magni 3 with CCA on high gain, I find that the amp sounds better at similar low volume levels as the low gain switch. However I have found that when listening to very loud levels I prefer the sound off of similar db levels from the low gain setting. When I listen to the rig via USB I flip the high gain on and I much prefer high gain with USB over any other means. I don't believe there is any gain coming from USB into my Mimby, and as such I have much better control over the volume level. After reading your explanation I am wondering if I was driving the Magni 3 into clipping with CCA and high gain.

Is anyone familiar enough with CCA to know if reducing the volume level within the Home app will impact SQ the way reducing volume on windows will affect SQ? The CCA tech support people are generally not knowledgeable enough to answer that question. I don't think CCA is truly geared towards the audio enthusiast. I think it's meant as a serve the masses product where louder is better.

 

[Rensek]

So I've been spending a bit of time the past few weeks on another audio site, which won't be named, but it's relatively new, has under 1500 members and is VERY big on measurements. I saw this article posted there tonight, and I thought it worth sharing.

https://www.stereophile.com/asweseeit/673awsi/index.html

 

[mithrandir38]

Opeth, what an awesome band. The most exquisite and perfect blend between metal & progressiveness.

I'll always thank Mike Portnoy for pointing me in their musical direction. Mikael A and company rule.

 

[jimmers]

Thanks to all for the knowledge. I think this last one gave me some welcome insight into the synergy of my Chromecast/Mimby/Magni3 path. I have long believed that the mini toslink output on my Chromecast Audio is inserting extra gain into my Mimby, which is then adding that same extra gain into my Magni 3. When I use the Magni 3 with CCA on high gain, I find that the amp sounds better at similar low volume levels as the low gain switch. However I have found that when listening to very loud levels I prefer the sound off of similar db levels from the low gain setting. When I listen to the rig via USB I flip the high gain on and I much prefer high gain with USB over any other means. I don't believe there is any gain coming from USB into my Mimby, and as such I have much better control over the volume level. After reading your explanation I am wondering if I was driving the Magni 3 into clipping with CCA and high gain.

Is anyone familiar enough with CCA to know if reducing the volume level within the Home app will impact SQ the way reducing volume on windows will affect SQ? The CCA tech support people are generally not knowledgeable enough to answer that question. I don't think CCA is truly geared towards the audio enthusiast. I think it's meant as a serve the masses product where louder is better.

If the CCA volume control alters the volume when going via S/PDIF to the Mimby to the Magni then it's doing it in a similar way to Windows volume control, i.e. not bit perfect.
The CCA cannot boost the level via S/PDIF as maximum level is 0 dBFS, it can only reduce it and only if the above is true.

 

[ItsAllInMyHead]

Thanks to all for the knowledge. I think this last one gave me some welcome insight into the synergy of my Chromecast/Mimby/Magni3 path. I have long believed that the mini toslink output on my Chromecast Audio is inserting extra gain into my Mimby, which is then adding that same extra gain into my Magni 3. When I use the Magni 3 with CCA on high gain, I find that the amp sounds better at similar low volume levels as the low gain switch. However I have found that when listening to very loud levels I prefer the sound off of similar db levels from the low gain setting. When I listen to the rig via USB I flip the high gain on and I much prefer high gain with USB over any other means. I don't believe there is any gain coming from USB into my Mimby, and as such I have much better control over the volume level. After reading your explanation I am wondering if I was driving the Magni 3 into clipping with CCA and high gain.

Is anyone familiar enough with CCA to know if reducing the volume level within the Home app will impact SQ the way reducing volume on windows will affect SQ? The CCA tech support people are generally not knowledgeable enough to answer that question. I don't think CCA is truly geared towards the audio enthusiast. I think it's meant as a serve the masses product where louder is better.

I'm glad it helped, but if you mean my post gave you insight... it seems it may not have and may have made it worse. I'm glad it helped with a basic understanding of gain, but I doubt "gain" in the strictest definition is contributing to what you're experiencing. Let me pull you away from that rabbit hole before you may fall into a black hole.

The short answer is that I doubt very much if you're driving the amp to clipping b/c the SPLs you'd be experiencing through any 300 ohm headphone I'm aware of at 11V output would be very, very bad. You'd know it, and you'd smoke some headphones. What I gave earlier was just the math and the simplest explanation of gain w/o much context.

We may want to take some of this to PM with some of the others in the group that are truly experts.... I'm at my limit of knowledge. You're asking good questions and seeking to understand, which is cool in my book. But, earlier you asked a fairly "narrow" question re: what's gain have to do with max power output. Our short answer is... it doesn't.

With the scenario you describe above, if you're wondering what's causing the sonic differences you're hearing... that's a whole 'nother kettle of fish, and there may not be one perfect answer. After many hours you might just shrug your shoulders.

A fundamental principal to understand and correct as you learn more is that each device (that contains an amplifier) has a gain. Gain = 1 means it's not an amplifier (pedants stay away ) Gain does not feed forward in a system. Your Mimby has a fixed output voltage no matter what feeds it and Toslink is an optical connection with no voltage passed from one component to the next. It's just passing light. That's one of the reasons why it's a pretty darn good system for audio. There's no electrical noise to go from point a to point b.

So, just by definition the Chomecast doesn't feed anything electrically to the Mimby through the Toslink... it feeds 1's and 0's by turning a light on and off (Pedants stay further away ) ... then the Mimby does it's magic to convert those 1's and 0's to a gorgeous analog signal and sends a fixed 2V output to the Magni. The only component with "gain" for the purposes of this discussion is the Magni.

What coooooooould be happening is if the Chromecast has a variable digital volume out... then at lower volumes, you are technically removing available dynamic range in the digital realm even before it gets to the Mimby. I'm guessing that this is what you mean re: your Windows question. Insert super complex boring explanation here...

What really matters is that I'd try turning your Chromecast volume all the way up all the time. Leave it there. Find the gain setting on your Magni that works well with your headphones. My guess is 2, but you could try 7. As long as you can get the volume knob past the point where you don't have channel imbalance, you're good to go. Same thing with any other source being fed to the Mimby though USB. Make sure the digital volume is all the way up and leave it there. Adjust the volume with the Magni only for best SQ*.

Do a very quick and dirty A/B after that. If one source (using the exact same digital file) is significantly louder or worse than the other, then report back. My guess is that there could be a sonic difference, but one shouldn't be appreciably louder or majorly different in sound quality than the other, and if it is - it shouldn't have anything to do with gain.

Edited to Add - SQ is subjective. You'll just have the best available dynamic range. You may like it more compressed. Everyone's different.

 

[wink]

obligatory cat pic :-