Recommendaton for DAC to drive AKG K701

[Swordsman]

Any recommendation as above ?

budget $300

 

[mrsun18]

Would like to know a recommendation for classical piano music and female vocal too. Listen to CD only.

 

[TeamStereo]

Any recommendation as above ?

budget $300

We have the iFi Audio iDAC that just came in =) Price is $399 but can drive the K702 fine so the K701 is okay as well. I don't have to go over 12 o'clock for the K702.

On promotion now for the iDAC it comes with a free Grado SR60i =)

 

[BlackOpal]

Would like to know a recommendation for classical piano music and female vocal too. Listen to CD only.

For female vocals, here's one i like by Connie Dover. I'm listening to Horowitz in Hamburg: The Last Concert [Live](classical piano) now

 

[Seth Lee]

We have the iFi Audio iDAC that just came in =) Price is $399 but can drive the K702 fine so the K701 is okay as well. I don't have to go over 12 o'clock for the K702.

On promotion now for the iDAC it comes with a free Grado SR60i =)

sorry, the idac alone will not do justice to the true potential of the k701. yes you get volume but not the raw grunt. the idea setup is idac to ican then to k701.

 

[nekatrall]

the O2 amp/objective 2 amp

 

[alamakazim]

k701 no need alot of juice... need a matching amp....

 

[mrsun18]

For female vocals, here's one i like by Connie Dover. I'm listening to Horowitz in Hamburg: The Last Concert [Live](classical piano) now

Thanks for your comments. I think you may have misunderstood me. I am not asking for recommendation on CD

 

[ckryan3]

Would like to know a recommendation for classical piano music and female vocal too. Listen to CD only.

So.... what are you asking for??

@TS: You'll need more than a DAC to drive the K701. You really need an amp for that as well.

 

[David_Can]

sorry, the idac alone will not do justice to the true potential of the k701. yes you get volume but not the raw grunt. the idea setup is idac to ican then to k701.

Not true, at 62ohms its not really as difficult to drive as many claims. If anything it's more of an slightly inefficient headphone due to the SPL rating. Like alamakazim mentioned, my experience with my previous pair of k701 was to find a matching amp/DAC combo to get the most out of the K701 sound signature. No doubt your recommendation of the iCan can do a better job but should also give the iDac a try since its really good value.

Speaking of which, I would be going down Stereo this afternoon to try.

 

[TeamStereo]

Thanks for your comments. I think you may have misunderstood me. I am not asking for recommendation on CD

Since you posted here, I believe you are looking for an amp as well? Do drop by our stores to try the iDAC - you can bring your headphones or use the ones we have in store.

 

[Fatty San]

Not true, at 62ohms its not really as difficult to drive as many claims. If anything it's more of an slightly inefficient headphone due to the SPL rating. Like alamakazim mentioned, my experience with my previous pair of k701 was to find a matching amp/DAC combo to get the most out of the K701 sound signature. No doubt your recommendation of the iCan can do a better job but should also give the iDac a try since its really good value.

Speaking of which, I would be going down Stereo this afternoon to try.

great! had tested the idac alone with q701 and idac + ican combo, there is much more body and texture to the music with the combo. have a go with both setup while you are there and really appreciate if you can share your experience with us.

 

[wwenze]

Lack of understanding can create confusion, consumers use the terms "drive" and "matching" to explain everything.

"Not enough voltage? Cannot drive."
"Not enough bass? Cannot drive."
"High impedance? Cannot drive."

At a sensitivity of 105dB SPL/V, K 701 would require an amplifier capable of 1V, 16mA, and 16mW to hit 105dB. In comparison, take HD650 with an impedance of 300Ω, it has a sensitivity of 103dB SPL/V, and would require 1.25V, 4.2mA and 5.2mW to hit 105dB.

 

[Dreammusic]

Lack of understanding can create confusion, consumers use the terms "drive" and "matching" to explain everything.

"Not enough voltage? Cannot drive."
"Not enough bass? Cannot drive."
"High impedance? Cannot drive."

At a sensitivity of 105dB SPL/V, K 701 would require an amplifier capable of 1V, 16mA, and 16mW to hit 105dB. In comparison, take HD650 with an impedance of 300Ω, it has a sensitivity of 103dB SPL/V, and would require 1.25V, 4.2mA and 5.2mW to hit 105dB.

So my macbook should be sufficient to drive the k701?

 

[rickysio]

Spec wise, technically possible, at least for MBA 5G. I assume the normal MBs are similar or better.

NwAvGuy: Apple MacBook Air 5G

 

[mrsun18]

So.... what are you asking for??

@TS: You'll need more than a DAC to drive the K701. You really need an amp for that as well.

As per thread's heading... After seeing yours and some others' comments, may be dac with amp is better.

Since you posted here, I believe you are looking for an amp as well? Do drop by our stores to try the iDAC - you can bring your headphones or use the ones we have in store.

Thanks for the invitation!

 

[mrsun18]

Lack of understanding can create confusion, consumers use the terms "drive" and "matching" to explain everything.

"Not enough voltage? Cannot drive."
"Not enough bass? Cannot drive."
"High impedance? Cannot drive."

At a sensitivity of 105dB SPL/V, K 701 would require an amplifier capable of 1V, 16mA, and 16mW to hit 105dB. In comparison, take HD650 with an impedance of 300Ω, it has a sensitivity of 103dB SPL/V, and would require 1.25V, 4.2mA and 5.2mW to hit 105dB.

Sorry, W = V x I only for dc. For ac with reactive or inductive load (impedance), W = V x IR where IR is the resistive component of the total current I.

As for your comment on ability to 'drive', I append below an extract of AKG 701 review by Stereophile:

The AKG will be a little harder to drive than, say, the 200 ohms of a typical Sennheiser design, but easier than the 30 ohms of a Grado. There should be no problems with good headphone amplifiers.—John Atkinson


Full review here:
AKG Acoustics K 701 headphones Measurements | Stereophile.com


Another extract from a different forum (sorry there are some may be not so relevant details):

From an electrical point of view, his comment about the Valhalla making no sense means this: K701 craves current. Vast amounts of current. Orthodynamic levels of current. Valhalla (or any OTL tube amp) is not known for pumping out crazy current....it's more about voltage (which is what high impedance cans like.) Conventional electrical wisdom says Valhalla (and other OTLs) = Beyer 600Ohm and other high impedance cans, Lyr and other hybrids/high-end SS amps = K701 and other low impedance current hungry cans. Senn 300ohm cans tend to go either way with different results.


Source: Best amp for K701 - my wallet is generous.


Furthemore, sensitivity is only a measurement to show how much input is required to achieve the sound pressure level (loudness, if you like, in laymen's term). But what would be the sound quality at this level (distortion)? A small car can travel at 100 km/hr as fast as a Rolls Royce going at the same speed. Which car would you prefer to be in?

 

[wwenze]

*cut*

Sorry, but you mixed textbook concepts with real-world products. Always need to consider "how much" and "relevance" of the effects. In the K 701 measurements that you linked, quote the article,

The AKG's impedance ranges between 60 and 65 ohms across most of the audioband, with a low electrical phase angle.

I will even bet that most headphones have near-zero phase across the majority of frequency bands, and if I am to be proven wrong I don't want to be doing the work for it.

The rest, if you want to nitpick, I have no qualms with that.

Add: For the heck of it, I came up with this graph using the 3-component model.

5nF capacitor parallel with a 300uH + 62R inductor.

 

[mrsun18]

@wwenze

It's marvelous we are engaging in a meaningful disscussion... The behaviour of real-world products can always be explained by text book knowledge (not just concepts but proven theories). It is a matter of how much details we want to go in to explain the behaviour (nitpick).

AKG 701 is considered a high quality product which reveals minute details in music, we cannot ignore the minor variations in the circuit which ultimately will affect the overall presentation.

It's good that you pick up the statement "The AKG's impedance ranges between 60 and 65 ohms across most of the audioband, with a low electrical phase angle." from the review.

If you look at Fig 1 in the review, it shows the impedance remains practically constant below 10KHz, and the phase angle remains practically zero below 5KHz. That means below the frequency range of 5~10 Khz, the AKG 701 is almost purely a resistive load, and your using W = V x I formula is agreeable. Beyond the 5~10 KHz range, the effect of inductive and capacitive load comes in and the formula is no longer valid.

Your graph of impedance and phase angle against frequency matches that in the review pretty well. Congratulations for producing a nice equivalent circuit!

 

[wwenze]

Again, "how much" (the effect is) comes into play. This graph shows the real power and apparent power for the circuit in post #18.

A impedance with a phase of 25.8 degrees will have the magnitude of the real component at 0.9 times the magnitude of the complex component. Calculating the real power is more difficult, but for phase angles of 25.8 degrees or less the real power can be considered to be close enough to the apparent power. Some even consider the other magic number of 45 degrees, when |r| = |i| = 1/sqrt(2) * |z|, since often we're only interested in differences of orders of magnitude. (log frequency scale and the use of dB)