[georgehifi]

Um... all headphones have power requirements.

Were talking milliwatts in the HD650, the worst opamps ( I'm sure Chord didn't use these) can supply this which is more than some tubes head phone amps can output. And then only "if" the output impedance of .042ohm can be maintained from 20hz to 20khz, as this was never given, only the 1khz figure.

Cheers George

 

[Music Alchemist]

Were talking milliwatts in the HD650, the worst opamps can supply this, and I'm sure Chord didn't use these.

You said headphones do not require current. That is the false claim I was addressing.

Here are the power requirements of the HD 650. (I calculated them before.)

Yes, they don't need a lot of power, but they still use current. That's the only point I was trying to make.

(These are just a rough guideline. Some music will use more power than listed above, especially when there is heavy bass.)

I have already covered that some people have driven headphones and speakers directly from the 2Qute. But the designer himself explained that it is limited in what it can do and has less power than the Hugo 2, for example.

Whether the Qutest can drive any given headphone to a certain SPL level depends on its power output specs, which have not been disclosed.

 

[dawktah2]

If I remember correctly.
V=I x R
P=V x I

I haven't seen current mentioned out of Qutest. Current is in "amps." Music Alchemist is correct Qutest needs and "amp"

 

[georgehifi]

You said headphones do not require current. That is the false claim I was addressing.
/QUOTE]

That's taking things out of text, What I compared it to was speaker needing current.

Any decent opamp with low output impedance can drive headphones if the voltage is there for the level needed, and in this case it seems it is, but that's the output stage, to back that up this need the power supply to be able to supply it.

Cheers George

 

[Music Alchemist]

Any decent opamp with low output impedance can drive headphones if the voltage is there for the level needed, and in this case it seems it is.

Some headphones, at least. Not harder to drive ones, though. I'll use the HIFIMAN HE6 as an example:

Music Alchemist is correct Qutest needs and "amp"

I never said that. In fact, I stated multiple times that people have driven headphones and speakers directly from the 2Qute (which outputs 3V), and some even preferred things that way. But at the least, it's going to be limited in terms of how loud you can get, depending on the impedance and sensitivity of the transducers.

All DACs (except the exotic MSB Select DAC, according to what MSB claim) have amplification of some sort, by the way.

If more specs for the Qutest were released (such as current and maximum output power at various input impedances), there would be less confusion.

 

[georgehifi]

.dawktah2 said:[/QUOTE]I never said that. In fact, I stated multiple times that people have driven headphones and speakers directly from the 2Qute (which outputs 3V), and some even preferred things that way. But at the least, it's going to be limited in terms of how loud you can get, depending on the impedance and sensitivity of the transducers.

All DACs (except the exotic MSB Select DAC, according to what MSB claim) have amplification of some sort, by the way.

If more specs for the Qutest were released (such as current and maximum output power at various input impedances), there would be less confusion.[/QUOTE]


+1 on this.
You'll find most dac's (except maybe tube output ones) able to drive headphones, even if they are only 2v redbok standard output, but in this case we have 3v almost more than enough to send you deaf.

Cheers George

 

[Triode User]

If more specs for the Qutest were released (such as current and maximum output power at various input impedances), there would be less confusion.

I’m sorry but that is just plain ridiculous. Qutest is a dac and not a headphone amp. I refer you back to my analogy of using a candle to try to heat a pan of water and then expecting the candle maker to publish heat output information regarding the candle. If you guys are suggesting using the Qutest for something that it is clearly not designed to do then you are out on your own and cannot expect Chord to publish data that might encourage you to do it.

 

[georgehifi]

Qutest is a dac and not a headphone amp. If you guys are suggesting using the Qutest for something that it is clearly not designed to do then you are out on your own .

Just because it doesn't have a headphone jack, doesn't mean it can't drive a pair of headphones to a certain level, maybe even better than some dedicated feeble tube headphone amps can.

Cheers George

 

[Triode User]

Just because it doesn't have a headphone jack, doesn't mean it can't drive a pair of headphones to a certain level, maybe even better than some dedicated feeble tube headphone amps can.

Cheers George

I am tiring of this. See it from a manufacturers perspective. The Qutest is a fixed output dac albeit with three different fixed outputs. Connecting a headphone to that requires somehow arranging variable volume control. If someone just plugs in headphones at 3v output and blows them or worse damages their hearing then there will be a lawsuit. Your persistence in somehow trying to engage Chord in the use of the Qutest to drive headphones direct is an agenda that you seem to want to pursue but you can see how you are unlikely to get Chord to participate in this. They are of course free to contradict me.

 

[georgehifi]

You've got yourself all twisted up over this.
No ones saying it's a headphone dac,
This all stemmed from the fact that the output impedance is so low at .042ohms (maybe? from 20hz to 20khz that wasn't confirmed) and with 3v output, it's very capable of driving headphones to a decent level, even better than some tube headphone amps can.

Cheers George

 

[miketlse]

You've got yourself all twisted up over this.
No ones saying it's a headphone dac,
This all stemmed from the fact that the output impedance is so low at .042ohms (maybe? from 20hz to 20khz that wasn't confirmed) and with 3v output, it's very capable of driving headphones to a decent level, even better than some tube headphone amps can.

Cheers George

Chord deliberately differentiated the 2Qute and Hugo, to fit into two different slots in their product line - the Hugo was a dac plus headphone amp (even if amp is rather a misnomer), and the 2Qute was the Hugo minus the battery and headphone amp, but with galvanic isolation on the usb input.
Chord have followed a similar policy with the Hugo2 and Qutest, so the initial Qutest design use cases, and product requirements will not have included the statement 'the product shall be able to direct drive headphones'.

You are always free to buy a Qutest, and discover whether using the Qutest outside its design space, by direct driving headphones is possible.
In the meantime you are building a reputation like another frequent poster on the chord threads, who recently was (humourously?) described as 'will endlessly debate the merits of eating soup with a fork'.

You expressed surprise that the Qutest output impedence is so low at 0.042 ohms, but that value will not have surprised long-term readers of the chord threads. The Mojo value is 0.075 ohms, and the Hugo 2 is 0.025 ohms.

You may enjoy this post from nearly two years ago.

 

[Music Alchemist]

I’m sorry but that is just plain ridiculous. Qutest is a dac and not a headphone amp. I refer you back to my analogy of using a candle to try to heat a pan of water and then expecting the candle maker to publish heat output information regarding the candle. If you guys are suggesting using the Qutest for something that it is clearly not designed to do then you are out on your own and cannot expect Chord to publish data that might encourage you to do it.

I am tiring of this. See it from a manufacturers perspective. The Qutest is a fixed output dac albeit with three different fixed outputs. Connecting a headphone to that requires somehow arranging variable volume control. If someone just plugs in headphones at 3v output and blows them or worse damages their hearing then there will be a lawsuit. Your persistence in somehow trying to engage Chord in the use of the Qutest to drive headphones direct is an agenda that you seem to want to pursue but you can see how you are unlikely to get Chord to participate in this. They are of course free to contradict me.

You are always free to buy a Qutest, and discover whether using the Qutest outside its design space, by direct driving headphones is possible.

Guys, I understand that Chord have their reasons for not discussing the ability of the Qutest and 2Qute to drive headphones and speakers directly (via the right cables) and releasing all the specs.

But the simple fact is, it can, and plenty of people have done so with good results, to the extent that some even preferred direct drive from the 2Qute over headphone and speaker amps in some cases. Obviously the volume would be limited for less sensitive transducers.

Anyone who has any idea what they're doing is going to take care of volume control in this situation. You can control the volume digitally, for example. foobar2000 has 32-bit processing. I'm not sure if that would qualify as bit-perfect volume control, but some say it does. There are other options, such as connecting to a preamp, but that would degrade the signal somewhat.

I transitioned from headphones to speakers last year and don't know when I will get back into headphones. I will certainly use external amps, but I would still like to experiment with direct drive to see if I get better sound, as some have discovered.

 

[theveterans]

Only reason the idea of getting a direct drive to a headphone is the unusually low output impedance, making it suitable to drive headphones with extremely good damping factor. Well if Chord desktop DACs have typical output resistance in the hundreds of ohms range like most other desktop DACs, probably no one would even think about using it as a headphone amp.

 

[gad1]

Does Chord hate America? Ok there is Trump, I get it,
but some of us need great audio to cope with the next
3 yrs. Have a little compassion and encourage/
pressure your USA distributors to sell Qutest at a
price in the vicinity of Englands adjusted for the
exchange rate

 

[JWahl]

Have a little compassion and encourage/
pressure your USA distributors to sell Qutest at a
price in the vicinity of Englands adjusted for the
exchange rate

In all fairness, I'm fairly certain Chord has already had to pressure the NA distributor to drop prices when the exchange rates changed. I would accept if they did a direct exchange rate from the British Pound cost, even though, to my knowledge, the British Pound cost includes the 20% VAT (If it doesn't, then someone please correct me). That markup should be more than enough to cover any shipping and import duties incurred by the distributor. Hopefully, the distributor doesn't try to get too greedy and mark it up even more, as the Stereophile article suggests. Though that could be an assumed price on the part of Stereophile, based on the initial price of the 2Qute before. If the price stays around $1600, I can accept that.