[grahamterry1000]

Hi
Just bought brand new Beyerdynamic DT770 Pro 80 ohms and coupled my iphone 12 via the lightning/phono dac to a second-hand Fiio A5 amp.

My limited funds meant I did a lot of research on which amp would power these cans but I am left disappointed with the resultant volume. I almost get the same volume directly out of the phone itself!

Both phone and amp volumes are set near full and the gain switch is also in use and whilst it is near the top end of comfortable listening volume I do like to be able to ramp it up occasionally! There is very little hiss or distortion which is good (and surprising) however I am wondering how I might get more power out of the A5 given that its official spec is 800mw at 32 ohms which should still translate down to a healthy output at 80 ohms and more than enough for these cans despite their relatively low sensitivity.

Might source power from the lightning port be an issue?

Any assistance for this newbie is welcome.

Thanks

 

[ProtegeManiac]

Hi
Just bought brand new Beyerdynamic DT770 Pro 80 ohms and coupled my iphone 12 via the lightning/phono dac to a second-hand Fiio A5 amp.

My limited funds meant I did a lot of research on which amp would power these cans but I am left disappointed with the resultant volume. I almost get the same volume directly out of the phone itself!

Both phone and amp volumes are set near full and the gain switch is also in use and whilst it is near the top end of comfortable listening volume I do like to be able to ramp it up occasionally! There is very little hiss or distortion which is good (and surprising)...

Just to make sure...the gain is on H, right?

Also the Lightning DAC you're using might actually not have that much less power than the A5, it may just have more distortion and noise at nearly the same power level but the thing what looks like a lot more power isn't always a lot more power, ie, double the power just gets slightly louder (assuming same distortion and noise), and for it to sound like it's twice as loud, you need 8X power. So for example if the power output of the A5 is around 300mW at 80ohms and the Lightning DAC has at least 150mW that means the difference in sheer output is just in the easily noticeable threshold, though in your case what makes it easier to tell the difference is the higher noise on the Lightning DAC, not how much louder it is.

In short assuming the gain settings work properly (ie the sound is softer if you set it to L) and so does everything else on that amp, you may just be overestimating how much that much power can do/underestimating how much more power will actually make a difference, while also underestimating how much power the Lightning DAC can spit out (if with higher noise).

...however I am wondering how I might get more power out of the A5 given that its official spec is 800mw at 32 ohms which should still translate down to a healthy output at 80 ohms and more than enough for these cans despite their relatively low sensitivity.

You can't just get "more power" out of any amp without extensive modifications. If you game on PC, what this means is this isn't a matter of loading up a BIOS that goes up to 600watts instead of 450watts - this is more like doing a shunt mod on a Kingpin card that has way overkill power stages so that you actually can pull more power and current when you pour NO2 (and in this example, getting errors on Port Royal that eventually gets your score taken down is the equivalent of audio amp noise).

What you can try getting is getting the max volume from having that amp driving a specific headphone. Without a dB meter though the only reference we have as to roughly how loud things are beyond suspecting that you can just tolerate playing louder is how little more volume there is past where the Lightning DAC would be. And since you got the amp used, a number of things can be wrong with it, like maybe the gain switch doesn't work. This is easy enough to test. Is it on H? If it is, does it go softer when on L? If it does then for the most part it can be assumed the switch at least is working properly.

Another possibility: since an amp input stage has a high impedance, that Lightning DAC could be outputting a softer signal as it "sees" a high impedance load past it because it's meant to be a compact amplifier circuit, not a line out circuit. So while it can output say 100mW to an 80ohm headphone it's entirely possible that its voltage is not that high then the impedance screws it up more, so the A5 effectively receives a much softer signal than what the headphone gets out of that DAC. This is trickier to diagnose...you need to test with a similar enough amp if not the same amp to see if the problem persists, or alternately, try a different DAC with a 2V line out to test that amp.

Might source power from the lightning port be an issue?

Any assistance for this newbie is welcome.

Thanks

Do you mean voltage of the audio signal from the Lightning DAC? If so then yeah there's a possibility that the A5 having a higher impedance input as amps do might mean it gets a softer signal from the Lightning DAC than if an 80ohm headphone were plugged into the same Lightning DAC, meaning the amp receives a softer signal and affects the overall system volume.


If what you meant was power ring the A5 from the iPhone Lightning port...er...how are you getting an audio signal into the A5 if the iPhone's only connectivity option that uses cables (ie not the wireless stuff like BT and WiFi) is being used for power? In any case, having any kind of charging current shouldn't really matter to an amp with a battery. Going back to the PC example, a portable audio amp doesn't work like a gaming laptop where the power limits for the CPU and more importantly the GPU can drop when you use a Type C charger (assuming the laptop in question has this feature) vs the regular 250w to 300w power brick because the CPU and GPU will then be limited to the 100w or 135w that the Type C charger can produce, which is nothing like what the factory power brick can deliver.

The closest thing to MSI Afterburner/EVGA Precision/etc on a portable audio amp is if its power stage has a charging chip that is smarter than the usual charging chips, which in this case isn't really modifying how the amp's output stage draws power the same way a GPU BIOS can have no power draw locks/limits, but can affect how much the battery dishes out. You can also test this easily - unplug the charger when listening. If it has this kind of feature in its charger chip it may even be louder without the charger.

Alternately if you have power plugged in because it otherwise won't run...that just means dead battery and unlike a gaming laptop you can't just run it with an effectively dead amp and only be concerned if it starts bloating. This still gets its power from the battery, unless amp charging chips now work like laptop power chips, which means battery health is very important. If the battery can't even hold a charge then the power output can drop because a battery in that condition won't produce the original voltage it was rated for.

 

[grahamterry1000]

Just to make sure...the gain is on H, right?

Also the Lightning DAC you're using might actually not have that much less power than the A5, it may just have more distortion and noise at nearly the same power level but the thing what looks like a lot more power isn't always a lot more power, ie, double the power just gets slightly louder (assuming same distortion and noise), and for it to sound like it's twice as loud, you need 8X power. So for example if the power output of the A5 is around 300mW at 80ohms and the Lightning DAC has at least 150mW that means the difference in sheer output is just in the easily noticeable threshold, though in your case what makes it easier to tell the difference is the higher noise on the Lightning DAC, not how much louder it is.

In short assuming the gain settings work properly (ie the sound is softer if you set it to L) and so does everything else on that amp, you may just be overestimating how much that much power can do/underestimating how much more power will actually make a difference, while also underestimating how much power the Lightning DAC can spit out (if with higher noise).




You can't just get "more power" out of any amp without extensive modifications. If you game on PC, what this means is this isn't a matter of loading up a BIOS that goes up to 600watts instead of 450watts - this is more like doing a shunt mod on a Kingpin card that has way overkill power stages so that you actually can pull more power and current when you pour NO2 (and in this example, getting errors on Port Royal that eventually gets your score taken down is the equivalent of audio amp noise).

What you can try getting is getting the max volume from having that amp driving a specific headphone. Without a dB meter though the only reference we have as to roughly how loud things are beyond suspecting that you can just tolerate playing louder is how little more volume there is past where the Lightning DAC would be. And since you got the amp used, a number of things can be wrong with it, like maybe the gain switch doesn't work. This is easy enough to test. Is it on H? If it is, does it go softer when on L? If it does then for the most part it can be assumed the switch at least is working properly.

Another possibility: since an amp input stage has a high impedance, that Lightning DAC could be outputting a softer signal as it "sees" a high impedance load past it because it's meant to be a compact amplifier circuit, not a line out circuit. So while it can output say 100mW to an 80ohm headphone it's entirely possible that its voltage is not that high then the impedance screws it up more, so the A5 effectively receives a much softer signal than what the headphone gets out of that DAC. This is trickier to diagnose...you need to test with a similar enough amp if not the same amp to see if the problem persists, or alternately, try a different DAC with a 2V line out to test that amp.






Do you mean voltage of the audio signal from the Lightning DAC? If so then yeah there's a possibility that the A5 having a higher impedance input as amps do might mean it gets a softer signal from the Lightning DAC than if an 80ohm headphone were plugged into the same Lightning DAC, meaning the amp receives a softer signal and affects the overall system volume.


If what you meant was power ring the A5 from the iPhone Lightning port...er...how are you getting an audio signal into the A5 if the iPhone's only connectivity option that uses cables (ie not the wireless stuff like BT and WiFi) is being used for power? In any case, having any kind of charging current shouldn't really matter to an amp with a battery. Going back to the PC example, a portable audio amp doesn't work like a gaming laptop where the power limits for the CPU and more importantly the GPU can drop when you use a Type C charger (assuming the laptop in question has this feature) vs the regular 250w to 300w power brick because the CPU and GPU will then be limited to the 100w or 135w that the Type C charger can produce, which is nothing like what the factory power brick can deliver.

The closest thing to MSI Afterburner/EVGA Precision/etc on a portable audio amp is if its power stage has a charging chip that is smarter than the usual charging chips, which in this case isn't really modifying how the amp's output stage draws power the same way a GPU BIOS can have no power draw locks/limits, but can affect how much the battery dishes out. You can also test this easily - unplug the charger when listening. If it has this kind of feature in its charger chip it may even be louder without the charger.

Alternately if you have power plugged in because it otherwise won't run...that just means dead battery and unlike a gaming laptop you can't just run it with an effectively dead amp and only be concerned if it starts bloating. This still gets its power from the battery, unless amp charging chips now work like laptop power chips, which means battery health is very important. If the battery can't even hold a charge then the power output can drop because a battery in that condition won't produce the original voltage it was rated for.

Hi
Thanks for your detailed reply.
Yes the Gain switch works.
I read about power (mw) increases only offering nominal db increases but thought I'd have plenty.
I also tried the set up with a pair of 32 ohm gaming headphones with the same outcome so not the cans.
These are Xmas present so have now been sent to Santa. Will have to play when I get them. Tbh I'm not sure what sound I was expecting so will get used to them and see how they go. Comparing them to Samsung Bluetooth earbuds tbh lol

 

[grahamterry1000]

Just to make sure...the gain is on H, right?

Also the Lightning DAC you're using might actually not have that much less power than the A5, it may just have more distortion and noise at nearly the same power level but the thing what looks like a lot more power isn't always a lot more power, ie, double the power just gets slightly louder (assuming same distortion and noise), and for it to sound like it's twice as loud, you need 8X power. So for example if the power output of the A5 is around 300mW at 80ohms and the Lightning DAC has at least 150mW that means the difference in sheer output is just in the easily noticeable threshold, though in your case what makes it easier to tell the difference is the higher noise on the Lightning DAC, not how much louder it is.

In short assuming the gain settings work properly (ie the sound is softer if you set it to L) and so does everything else on that amp, you may just be overestimating how much that much power can do/underestimating how much more power will actually make a difference, while also underestimating how much power the Lightning DAC can spit out (if with higher noise).




You can't just get "more power" out of any amp without extensive modifications. If you game on PC, what this means is this isn't a matter of loading up a BIOS that goes up to 600watts instead of 450watts - this is more like doing a shunt mod on a Kingpin card that has way overkill power stages so that you actually can pull more power and current when you pour NO2 (and in this example, getting errors on Port Royal that eventually gets your score taken down is the equivalent of audio amp noise).

What you can try getting is getting the max volume from having that amp driving a specific headphone. Without a dB meter though the only reference we have as to roughly how loud things are beyond suspecting that you can just tolerate playing louder is how little more volume there is past where the Lightning DAC would be. And since you got the amp used, a number of things can be wrong with it, like maybe the gain switch doesn't work. This is easy enough to test. Is it on H? If it is, does it go softer when on L? If it does then for the most part it can be assumed the switch at least is working properly.

Another possibility: since an amp input stage has a high impedance, that Lightning DAC could be outputting a softer signal as it "sees" a high impedance load past it because it's meant to be a compact amplifier circuit, not a line out circuit. So while it can output say 100mW to an 80ohm headphone it's entirely possible that its voltage is not that high then the impedance screws it up more, so the A5 effectively receives a much softer signal than what the headphone gets out of that DAC. This is trickier to diagnose...you need to test with a similar enough amp if not the same amp to see if the problem persists, or alternately, try a different DAC with a 2V line out to test that amp.






Do you mean voltage of the audio signal from the Lightning DAC? If so then yeah there's a possibility that the A5 having a higher impedance input as amps do might mean it gets a softer signal from the Lightning DAC than if an 80ohm headphone were plugged into the same Lightning DAC, meaning the amp receives a softer signal and affects the overall system volume.


If what you meant was power ring the A5 from the iPhone Lightning port...er...how are you getting an audio signal into the A5 if the iPhone's only connectivity option that uses cables (ie not the wireless stuff like BT and WiFi) is being used for power? In any case, having any kind of charging current shouldn't really matter to an amp with a battery. Going back to the PC example, a portable audio amp doesn't work like a gaming laptop where the power limits for the CPU and more importantly the GPU can drop when you use a Type C charger (assuming the laptop in question has this feature) vs the regular 250w to 300w power brick because the CPU and GPU will then be limited to the 100w or 135w that the Type C charger can produce, which is nothing like what the factory power brick can deliver.

The closest thing to MSI Afterburner/EVGA Precision/etc on a portable audio amp is if its power stage has a charging chip that is smarter than the usual charging chips, which in this case isn't really modifying how the amp's output stage draws power the same way a GPU BIOS can have no power draw locks/limits, but can affect how much the battery dishes out. You can also test this easily - unplug the charger when listening. If it has this kind of feature in its charger chip it may even be louder without the charger.

Alternately if you have power plugged in because it otherwise won't run...that just means dead battery and unlike a gaming laptop you can't just run it with an effectively dead amp and only be concerned if it starts bloating. This still gets its power from the battery, unless amp charging chips now work like laptop power chips, which means battery health is very important. If the battery can't even hold a charge then the power output can drop because a battery in that condition won't produce the original voltage it was rated for.

Another thought.
If I used the lightning / USB camera adapter and plugged in a combo dac/amp would that work do you think? Am I limited to the signal coming out of the lightning port? Don't know if that sends different power out as it's USB. The A5 is a pure amp so taking the dac phono adapter out leaves me with no analogue signal hence a new dac.

 

[ProtegeManiac]

I read about power (mw) increases only offering nominal db increases but thought I'd have plenty.

Technically the A5 does have plenty of power if judged on its own, but given you need far more power to get louder, and how the dongle might have a lot of power, you're gonna need a heck lot more power.

That or it's my other guess that the dongle being an amplified output might be "seeing" the impedance of the A5's input and thinks it's driving a very old headphone and produces a weaker signal.

Another thought.
If I used the lightning / USB camera adapter and plugged in a combo dac/amp would that work do you think?

That could be one way around it, assuming my guess about how the dongle's output may be reduced significantly by a high impedance input stage. It's not a matter of software not being able to tell a high impedance headphone from an even higher impedance amp input stage - it's just that depending on the power and voltage capability of the amp circuit (which in this case is a single chip with everything on it) this issue can happen.

That said if you decide to get a DAC-HPamp you're gonna need to make sure it produces comparable (preferably a little bit more) power as the A5 otherwise, without knowing how much power the dongle actually makes to be more sure if it was mostly just the above guess or if it actually has a fair bit of power (if with more noise), you can just run into a similar issue where the DAC-HPamp isn't that much louder. And the problem here is the A5 is relatively cheap for its power output because it's just an amp - if you get a portable amp with as much power but also has a DAC this will get expensive.

Am I limited to the signal coming out of the lightning port? ... The A5 is a pure amp so taking the dac phono adapter out leaves me with no analogue signal hence a new dac.

Well you could get a DAC-HPamp unit with BT and a line output.* Connect the iPhone via BT, then drive the headphone directly. If it's not much louder than the dongle, then connect the line out to the A5. At least in this case you won't need to spend as much money on a very powerful portable DAC-HPamp unit, and just in case connecting that line out to the A5 still isn't loud enough, you already have a DAC with a line out and you just try a more powerful amplifier. Speaking of which, do you really prefer portables? Because this can all be simplified by using desktop stuff. Maybe use a DAC-HPamp with modest power on the go and preferably with IEMs that you can get later on but at home just use a desktop amp hooked up to wall power.

*Alternately you can still use the CCK to hook up to the DAC-HPamp unit, just make sure it's got a line output so you can connect it to the A5 easily. Although to be honest unless you're using FLAC and such I wouldn't bother really. If you're just using Spotify for example the 320kbps compression doesn't require additional compression to go through BT so you're not losing anything.

Don't know if that sends different power out as it's USB.

If by power you mean USB power then it's the same 5V/500mA AFAIK.

If by power you mean (mili)watts of audio signal then that really depends on what it's hooked up to. Some dongle DACs/USB thumb drive form factor DACs can produce a lot of power with just 5V/500mA, but that's at 16ohms or 32ohms; power drops more drastically above that due to the limited voltage and current. Some DAC-HPamps may also produce a line output (whether to its own amp section or if it has an output for that) at 1.2V to 2V using the same 5V/500mA. In most cases it won't matter as much if it's 5V/500mA since the battery is the main power source, except in cases like the Ibasso D-Zero where the headphone amp is hooked up to its battery but the USB receiver and DAC chips plus the output stage all get their power from the USB host device hooked up to the D-Zero.

 

[grahamterry1000]

Technically the A5 does have plenty of power if judged on its own, but given you need far more power to get louder, and how the dongle might have a lot of power, you're gonna need a heck lot more power.

That or it's my other guess that the dongle being an amplified output might be "seeing" the impedance of the A5's input and thinks it's driving a very old headphone and produces a weaker signal.




That could be one way around it, assuming my guess about how the dongle's output may be reduced significantly by a high impedance input stage. It's not a matter of software not being able to tell a high impedance headphone from an even higher impedance amp input stage - it's just that depending on the power and voltage capability of the amp circuit (which in this case is a single chip with everything on it) this issue can happen.

That said if you decide to get a DAC-HPamp you're gonna need to make sure it produces comparable (preferably a little bit more) power as the A5 otherwise, without knowing how much power the dongle actually makes to be more sure if it was mostly just the above guess or if it actually has a fair bit of power (if with more noise), you can just run into a similar issue where the DAC-HPamp isn't that much louder. And the problem here is the A5 is relatively cheap for its power output because it's just an amp - if you get a portable amp with as much power but also has a DAC this will get expensive.





Well you could get a DAC-HPamp unit with BT and a line output.* Connect the iPhone via BT, then drive the headphone directly. If it's not much louder than the dongle, then connect the line out to the A5. At least in this case you won't need to spend as much money on a very powerful portable DAC-HPamp unit, and just in case connecting that line out to the A5 still isn't loud enough, you already have a DAC with a line out and you just try a more powerful amplifier. Speaking of which, do you really prefer portables? Because this can all be simplified by using desktop stuff. Maybe use a DAC-HPamp with modest power on the go and preferably with IEMs that you can get later on but at home just use a desktop amp hooked up to wall power.

*Alternately you can still use the CCK to hook up to the DAC-HPamp unit, just make sure it's got a line output so you can connect it to the A5 easily. Although to be honest unless you're using FLAC and such I wouldn't bother really. If you're just using Spotify for example the 320kbps compression doesn't require additional compression to go through BT so you're not losing anything.





If by power you mean USB power then it's the same 5V/500mA AFAIK.

If by power you mean (mili)watts of audio signal then that really depends on what it's hooked up to. Some dongle DACs/USB thumb drive form factor DACs can produce a lot of power with just 5V/500mA, but that's at 16ohms or 32ohms; power drops more drastically above that due to the limited voltage and current. Some DAC-HPamps may also produce a line output (whether to its own amp section or if it has an output for that) at 1.2V to 2V using the same 5V/500mA. In most cases it won't matter as much if it's 5V/500mA since the battery is the main power source, except in cases like the Ibasso D-Zero where the headphone amp is hooked up to its battery but the USB receiver and DAC chips plus the output stage all get their power from the USB host device hooked up to the D-Zero.

Hi

Thanks for taking the time to reply, appreciate it.


What reasonably priced amp would you recommend for home use?

 

[ProtegeManiac]

What reasonably priced amp would you recommend for home use?

If the primary goal was a lot of usable power for not a lot of money (nor complications, as other amps can do more but not with single ended connections) ie just getting a heck lot of power to make sure you can go louder (just in case your dongle does produce more power than smartphones and is closer to an entry level DAP), then I'd say just get the Schiit Magni3 and pour over 1watt into the headphone.

That said in case I'm right about impedance interactions with that dongle you might want to use a DAC with a real line out to totally avoid that, and preferably with a 2V line output. There's the Modi 3 to go with that Magni3