[Brooko]

It depends, it was nowhere near enough for my sennheiser hd 540, it needs a lot more power than what k5 can offer, for 150 ohm headphones and lower it does seem to have enough power. But not even close for 300 ohm ones. would never recommend it as amp. It is way worse at being an amp than any of fiios amp modules(they are better in every possible way except power) only thing going for it is a bit more power, but it only is a bit more and would not even close for 300ohm cans.

??? - you're talking about the K5 desktop amp right.

AM5 module will put 55 mW into 300 ohms (11 Vp-p, max current output 250 mA)
AM3A balanced will put 63 mW into 300 ohms (10 Vp-p, max current output 150 mA)

K5 will put 150 mW into 300 ohms (20 Vp-p, max current output 220 mA)

It's essentially transparent (wire with gain) and has output impedance of under 1 ohm. If FiiO had an adjustable rear RCA (so I could control my active monitors with the pot), then K5 + Q5 would be enough for me (and I'd imagine most other users). It has plenty of power, and can easily handle up to 600 ohm headphones (depending on sensitivity). Its perfect for headphones like the HD800S or HD600/650.

The reason the HD540 are so hard to drive is that their nominal impedance is only 94 db/mW, and combined with 300 ohm impedance, you need a really beefy amp to drive them. This is no slight on the K5 though. Its a bit like calling an amp weak for not being able to drive an HE6. The reality is that few amps can.

Most 300 ohm loads K5 will handle easily.

 

[397324]

So for an easy to drive headphone or IEM you need a higher impedance and lower ohm rating? Are they both equally important?

 

[majo123]

I don't think there is a queue feature on the x7ii (correct me if I'm wrong) would be nice to see one implemented if not.

 

[Dobrescu George]

So for an easy to drive headphone or IEM you need a higher impedance and lower ohm rating? Are they both equally important?

SPL means how easy it makes sound, how efficient for each mW that headphone is. Bellow 98, this usually means it is rather quiet compared to something with a similar impedance but with a higher SPL

Impedance is how much resistance to the signal there is. Higher impedance matters above 150 OHM in general. 14, 16, 32, 64, and 150 OHM are different, but the differences matter less than say, when you compare something with SPL 120dB and something with SPL 95DB

Very low impedance can cause issues, like hiss and impedances mistmatch, and somethign with very high impedance, like 600 OHM becomes harder to drive

FiiO X7mkii with AMP5 can usually drive HD600 really well to my ears, along with driving Beyerdynamic Amiron and LCD-MX4, all with excellent sonic characteristics.

 

[397324]

Thanks for the answer.

 

[lantian]

??? - you're talking about the K5 desktop amp right.

AM5 module will put 55 mW into 300 ohms (11 Vp-p, max current output 250 mA)
AM3A balanced will put 63 mW into 300 ohms (10 Vp-p, max current output 150 mA)

K5 will put 150 mW into 300 ohms (20 Vp-p, max current output 220 mA)

It's essentially transparent (wire with gain) and has output impedance of under 1 ohm. If FiiO had an adjustable rear RCA (so I could control my active monitors with the pot), then K5 + Q5 would be enough for me (and I'd imagine most other users). It has plenty of power, and can easily handle up to 600 ohm headphones (depending on sensitivity). Its perfect for headphones like the HD800S or HD600/650.

The reason the HD540 are so hard to drive is that their nominal impedance is only 94 db/mW, and combined with 300 ohm impedance, you need a really beefy amp to drive them. This is no slight on the K5 though. Its a bit like calling an amp weak for not being able to drive an HE6. The reality is that few amps can.

Most 300 ohm loads K5 will handle easily.

Thank you for the info, in any case I would not recommend K5 as a headphone amp, there are better options.
As far as better amps go, for my hd 535(150 ohm) and my akg k400(100ohm) the am1 and am3a modules have better layering/detail/imaging but less power/dynamics. As i said before in my opinion the amp modules for x7 and x7mk2 are all better in every way except for power. So far the 4 people i asked to compare said the same thing. That the small amps sound better, but don't have quite as much power and dynamics.

 

[Brooko]

Power is power - as long as you have enough to drive a headphone properly, in my experience thats all that matters. So you are saying that X7ii with AM3A or AM5 is better on high impedance headphones than X7ii + K5? As far as "layering / imaging / etc, etc" - that is the recording + the dac + the headphones being driven properly. It is not a property of the amp. In this case you have the same DAC, the same source. Unless AM3A or AM5 are colouring the sound, and you prefer coloured sound - then that doesn't really make sense.

If K5 was simply an amp module with the same sound, but all that additional power, I'd be willing to bet that you and your 4 friends would prefer the K5 module.

The secret to really knowing:

1. Proper volume matching (not by ear)
2. Very quick switching
3. Blind - so you don't know the source.

I'll stand by my experience with the K5 - very clean, very transparent, reasonable power output for most headphones - and great with FiiO compatible products (especially Q5).

 

[lantian]

Power is power - as long as you have enough to drive a headphone properly, in my experience thats all that matters. So you are saying that X7ii with AM3A or AM5 is better on high impedance headphones than X7ii + K5? As far as "layering / imaging / etc, etc" - that is the recording + the dac + the headphones being driven properly. It is not a property of the amp. In this case you have the same DAC, the same source. Unless AM3A or AM5 are colouring the sound, and you prefer coloured sound - then that doesn't really make sense.

If K5 was simply an amp module with the same sound, but all that additional power, I'd be willing to bet that you and your 4 friends would prefer the K5 module.

The secret to really knowing:

1. Proper volume matching (not by ear)
2. Very quick switching
3. Blind - so you don't know the source.

I'll stand by my experience with the K5 - very clean, very transparent, reasonable power output for most headphones - and great with FiiO compatible products (especially Q5).

No I stand by it being the property of the amp, since with k5 I have less details, worse imaging/layering etc. With am1 or am3a I get better imaging/ layering/more details, from either x7 or x7mk2. The am1 and m3a in my case have to be turned up with high gain. Again as far as I can say i would never call k5 a good amp.

 

[Brooko]

Pointless debating it. All I can tell you is that a lower power amp module isn't going to magically improve layering or imaging. That is solely the recording and the transducer. And there is no way (from the specs) that the K5 can be worse than the other two modules. Electrically impossible.

The only other things that it can be are:
- sighted bias
- volume mis-match

But as long as you are enjoying them - it doesn't matter anyway.

 

[lantian]

Pointless debating it. All I can tell you is that a lower power amp module isn't going to magically improve layering or imaging. That is solely the recording and the transducer. And there is no way (from the specs) that the K5 can be worse than the other two modules. Electrically impossible.

The only other things that it can be are:
- sighted bias
- volume mis-match

But as long as you are enjoying them - it doesn't matter anyway.

All I can say. I hear the exact opposite. till i got the k5 was actually inclined to believe your opinion, not anymore it just doesn't work that way. Let me just say, that power is not everything, otherwise better amps would not exist.

 

[Brooko]

Given that the THD and SNR numbers for all the amps mentioned are below the threshold of audibility, what else can affect it? Yes - power is not everything, but if all the other properties of the amps discussed are comparable - why do you hear a difference? And I have all those amps, and X7ii. I have a very revealing headphone in the HD800S. I’ve put the K5 up against amps in the $500+ range, and with a good source docked (Q5, X7ii etc) it holds its own (IMO) with headphones such as the HD600, HD800S and even 600 ohm T1.

The AM5 module is clearly coloured (warmer), but the AM3A and K5 are tonally very similar.

I guess I just value transparency and it comes down to preference. But please don’t tell me that the AM3A (with a hard to drive headphone) is going to outperform the K5. It can’t.

 

[colinallcarz]

Thanks for the info. I'll update with my findings in the K5 and go from there.

 

[lantian]

Given that the THD and SNR numbers for all the amps mentioned are below the threshold of audibility, what else can affect it? Yes - power is not everything, but if all the other properties of the amps discussed are comparable - why do you hear a difference? And I have all those amps, and X7ii. I have a very revealing headphone in the HD800S. I’ve put the K5 up against amps in the $500+ range, and with a good source docked (Q5, X7ii etc) it holds its own (IMO) with headphones such as the HD600, HD800S and even 600 ohm T1.

The AM5 module is clearly coloured (warmer), but the AM3A and K5 are tonally very similar.

I guess I just value transparency and it comes down to preference. But please don’t tell me that the AM3A (with a hard to drive headphone) is going to outperform the K5. It can’t.

As I said before the am3a am1 modules sound better in every aspect, excluding lack of power.

 

[colinallcarz]

So when you plug the X7 mkii (let's say with the AM3A attached) into the K5, are you bypassing the dac on the X7 for the one in the K5? I would hope you could use the dac from the X7 and then just amplify the signal with the more powerful K5

This part of the hobby makes my head spin.

 

[Victorfabius]

So when you plug the X7 mkii (let's say with the AM3A attached) into the K5, are you bypassing the dac on the X7 for the one in the K5? I would hope you could use the dac from the X7 and then just amplify the signal with the more powerful K5

This part of the hobby makes my head spin.

As far as I'm aware, the K5 does not posess a dac. You'd be utilizing the dac on the X7 and bypassing the AM3A amp for the K5. It's a slightly elegant solution for those who need that extra power.