TwoEars
500+ Head-Fier
- Joined
- Mar 16, 2011
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My Theory on Balanced vs Single Ended for High/Low Impedance Headphones ####################################################
Edit & Disclaimer: This post contains errors that shows that I'm no EE, what follows is a discussion on the topic.
Basically the idea goes like this:
#####################
1) Balanced might improve channel separation and imaging in theory, but in practice the channel separation for singel ended already has a 90dB noise floor or more. So balanced shoudn't really improve imaging relative to SE in practice (balanced might improve imaging but if so it is d/t other factors which we'll discuss later).
2) Balanced has a definitive disadvantage in that you need twice the amount of components and the push/pull has to match perfectly timing wise. So there is actually a much greater risk of messing up the imaging with balanced and making it powerful but "fuzzy".
3) Since balanced has twice the internal components it is usally better to go for a really good SE amplifier than a mediocre balanced for the same amount of money. This beeing said there will be a big difference between high impedance headphones with well dampending membranes (HD650, T1, HD800) and low impedance headphone (LCD2/3, HifiMan).
If the headphones have high impedance:
###########################
The headphone membranes now act as a resistor on the signal and prevent the electrical current from flowing freely towards ground, the more resistans the slower the respons from the membranes. It will take a beefy amp that doesn't care about resistance to make a pair of HD650, HD800 or T1's come alive.
A balanced amp can really help here since instead of just "pushing" on the coil and membrane the amp is now pulling on the headphone coil and membrane as well. This should really help hard to drive headphone come alive and offer better control, deeper bass and faster respons. This is also where the percieved improved imaging comes from - and not the increased channel separation as mentioned in "1)" above.
If the headphone have low impedance:
##########################
The headphone membrane still act as a resistor but to a much lesser extent, what is needed now to drive the headphones is not primarily an amp that is "beefy" (and ignores resistance) but rather one that can deliver lots of current into low loads. A balanced amp is not going to help that much here since amp circuits usually are designed for a certain maximum effienct throughput.
And it doesn't help to have two circuits connected in tandem in a push/pull configuration if both are running out of throughput at the same time. Instead what is needed is the ability to push lots and lots of current into low loads without running out of juice. Which is also why the best matches for HE-6 tends to be tube amp that can deliever a lot of current or even solid state speaker amps.
So in summary:
##########
1) I believe that balanced can offer significant sonic improvements to hard to drive headphones with high resistance such as the HD650/HD800/T1.
2) I do however not believe that balanced should offer any noticiable (or justifiable) upgrade for low impedance headphones (Hifiman & LCD2-3 in particular). Instead for the same money what you need is the best SE amp you can get that delievers a lot of current and can do it cleanly.
What do you think? Does it reflect your listening experience? Any electrical engineers / circuit designers among us who can offer technical feedback and/or corrections?
Discuss!
Edit & Disclaimer: This post contains errors that shows that I'm no EE, what follows is a discussion on the topic.
Basically the idea goes like this:
#####################
1) Balanced might improve channel separation and imaging in theory, but in practice the channel separation for singel ended already has a 90dB noise floor or more. So balanced shoudn't really improve imaging relative to SE in practice (balanced might improve imaging but if so it is d/t other factors which we'll discuss later).
2) Balanced has a definitive disadvantage in that you need twice the amount of components and the push/pull has to match perfectly timing wise. So there is actually a much greater risk of messing up the imaging with balanced and making it powerful but "fuzzy".
3) Since balanced has twice the internal components it is usally better to go for a really good SE amplifier than a mediocre balanced for the same amount of money. This beeing said there will be a big difference between high impedance headphones with well dampending membranes (HD650, T1, HD800) and low impedance headphone (LCD2/3, HifiMan).
If the headphones have high impedance:
###########################
The headphone membranes now act as a resistor on the signal and prevent the electrical current from flowing freely towards ground, the more resistans the slower the respons from the membranes. It will take a beefy amp that doesn't care about resistance to make a pair of HD650, HD800 or T1's come alive.
A balanced amp can really help here since instead of just "pushing" on the coil and membrane the amp is now pulling on the headphone coil and membrane as well. This should really help hard to drive headphone come alive and offer better control, deeper bass and faster respons. This is also where the percieved improved imaging comes from - and not the increased channel separation as mentioned in "1)" above.
If the headphone have low impedance:
##########################
The headphone membrane still act as a resistor but to a much lesser extent, what is needed now to drive the headphones is not primarily an amp that is "beefy" (and ignores resistance) but rather one that can deliver lots of current into low loads. A balanced amp is not going to help that much here since amp circuits usually are designed for a certain maximum effienct throughput.
And it doesn't help to have two circuits connected in tandem in a push/pull configuration if both are running out of throughput at the same time. Instead what is needed is the ability to push lots and lots of current into low loads without running out of juice. Which is also why the best matches for HE-6 tends to be tube amp that can deliever a lot of current or even solid state speaker amps.
So in summary:
##########
1) I believe that balanced can offer significant sonic improvements to hard to drive headphones with high resistance such as the HD650/HD800/T1.
2) I do however not believe that balanced should offer any noticiable (or justifiable) upgrade for low impedance headphones (Hifiman & LCD2-3 in particular). Instead for the same money what you need is the best SE amp you can get that delievers a lot of current and can do it cleanly.
What do you think? Does it reflect your listening experience? Any electrical engineers / circuit designers among us who can offer technical feedback and/or corrections?
Discuss!