The Qudelix-5K thread

[lowrider007]

In case you do not know:
- It takes a 10dB increase in volume to sound twice as loud.
- It requires about 10 times the power to sound twice as loud.
So don't expect huge volume increases going from 1V to 2V output.

But what do people mean they say "needs more juice" or "likes current", I'm just trying to understand these phrases, how do you attain that? I thought higher powered amps just meant more headroom before distortion, for example if you have two headphone amps both volume matched, one amp is 1w, the other is 6w, is the 6w amp giving the headphone/IEM "more juice/current" than the 1w amp at the same volume?

Sorry if this is a confusing question.

 

[04gto]

Thanks.

That being the case when reading the following in a review,,

"P1 MAX is not that easy to drive and needs a powerful source with plenty of current delivery.."

What does that mean exactly and how do you achieve that? I'm guessing upping the voltage on the Qualex doesn't attain that as playing at the same volume it's still @ 150mv, what if you maxed out the volume @ 2v on the Qudelix and then controlled the volume on the phone instead, would that provide more 'current'?

This phrase really means nothing:
"P1 MAX is not that easy to drive and needs a powerful source with plenty of current delivery..". Power and current are relative. How much power and current? So based on this statement alone, there is nothing to "attain". Somewhere on the Qudelix website (maybe the user guide), I read that the output in MA goes up like 50% (+/-) when switching from 1v to 2v. However if you want real current, use the 2.5 balanced connection. The 4v balanced basically doubles the current output. Again these are not exact numbers, just rounded numbers that I recall from Qudelix literature. Feel free to look it up on their page.

Also to match the quoted specs for the Qudelix you would indeed need to max out the phone volume and control volume from the Q5K.

 

[lowrider007]

This phrase really means nothing:
"P1 MAX is not that easy to drive and needs a powerful source with plenty of current delivery..". Power and current are relative. How much power and current? So based on this statement alone, there is nothing to "attain". Somewhere on the Qudelix website (maybe the user guide), I read that the output in MA goes up like 50% (+/-) when switching from 1v to 2v. However if you want real current, use the 2.5 balanced connection. The 4v balanced basically doubles the current output. Again these are not exact numbers, just rounded numbers that I recall from Qudelix literature. Feel free to look it up on their page.

Also to match the quoted specs for the Qudelix you would indeed need to max out the phone volume and control volume from the Q5K.

Interesting thanks, Balanced it is then, just trying to understand as these (P1 Max) are the first IEM's I've got that don't sound great on the single ended output of the Qudelix but sound amazing on my MOJO 2 and Deckard desktop amp.

 

[04gto]

Interesting thanks, Balanced it is then, just trying to understand as these (P1 Max) are the first IEM's I've got that don't sound great on the single ended output of the Qudelix but sound amazing on my MOJO 2 and Deckard desktop amp.

Keep in mind that sometimes it is just certain amp/earphone pairings just sound better, regardless of power outputs or requirements.

 

[3fifty]

Interesting thanks, Balanced it is then, just trying to understand as these (P1 Max) are the first IEM's I've got that don't sound great on the single ended output of the Qudelix but sound amazing on my MOJO 2 and Deckard desktop amp.

I think there may be some confusion here;

However if you want real current, use the 2.5 balanced connection. The 4v balanced basically doubles the current output

If the current goes up, the volume goes up. Doubling the 'possible' output current won't change anything if you aren't turning the volume up. This is one of those audiophile myths that just doesn't make sense if you think in terms of how the amplifier works.

Qudelix has a blog post that might help.

 

[lowrider007]

I think there may be some confusion here;



If the current goes up, the volume goes up. Doubling the 'possible' output current won't change anything if you aren't turning the volume up. This is one of those audiophile myths that just doesn't make sense if you think in terms of how the amplifier works.

Qudelix has a blog post that might help.

Right, this is what I thought, so when people say "X headphone needs juice/current" to sound good this is a fallacy because you can't have extra current without turning the volume?

 

[3fifty]

Right, this is what I thought, so when people say "X headphone needs juice/current" to sound good this is a fallacy because you can't have extra current without turning the volume?

Exactly. If it’s loud enough, you have enough power. The 5k will drive the HE6v2 (50ohm/83.5dBpmW) at 108.6dB at 4V. You could run -8dB for EQ headroom, and still be looking at hearing damage after 15 mins.

As for why it sounds different to your other amps…are you sure you have the volume matched exactly?

If so, apply a bit of EQ and see if you can match the others. I’d be interested to see what the difference is.

 

[killermax]

Hi!
I just joined the club. Is there any way to adjust the EQ with a slider rather than inputting numbers?
Do you have any recommended settings for a custom JH16 v1? I tried the v2 preset and it was horrible.

 

[3fifty]

Hi!
I just joined the club. Is there any way to adjust the EQ with a slider rather than inputting numbers?
Do you have any recommended settings for a custom JH16 v1? I tried the v2 preset and it was horrible.

DSP page -> DSP tab -> G.E.Q.

 

[killermax]

DSP page -> DSP tab -> G.E.Q.

Thanks so much. You are a life saver.

 

[mikeyhd]

Does anyone with 2 (QTY 2) Qudelix? every time I change devices, have to connect and disconnect, it has become a pain in the as*

 

[michusxx]

Exactly. If it’s loud enough, you have enough power. The 5k will drive the HE6v2 (50ohm/83.5dBpmW) at 108.6dB at 4V. You could run -8dB for EQ headroom, and still be looking at hearing damage after 15 mins.

As for why it sounds different to your other amps…are you sure you have the volume matched exactly?

If so, apply a bit of EQ and see if you can match the others. I’d be interested to see what the difference is.

Hi.
I have small correction to HE6v2 example.
To apply 25dB of amplification (required to reach 108.6dB level) you would need 320mW of output power. Q5k is limited to 240mW so in fact what you can get is 23.8dB. It is still extremely loud volume level (107.3dB) but more important it shows specific limitation - output current limit. And it is something that might appear as problem with driving some low impedance and extremely low sensitivity headphones. You can face it also doing EQ of headphones by boosting low bass as this might require extra dB comparing to reference 1kHz area. So these 25dB of amplification will not be used for reaching 108dB of general volume but for providing power to correct shortcomings in bass area.
Looking at specs of TINHIFI P1 MAX that were the starting point for this discussion - they are 16 Ohm and 98dB/1mW. Even with SE output of Q5k we can get 19dB (80mW) of amplification. And looking at P1 frequency characteristics that shouldn't be problem even with the lowest bass (EQ). But I can imagine that driving them directly from 3.5mm output from smartphone (or other small portable device) might be more "challenging" due to its low impedance.
Concluding. Q5k is quite powerful for both - high impedance (4V at balanced output) and low impedance (80/240mW SE/BAL) phones. But we can find some "special" cases where we might face one of its limit - voltage or current...

 

[Guipnox]

Hi.
I have small correction to HE6v2 example.
To apply 25dB of amplification (required to reach 108.6dB level) you would need 320mW of output power. Q5k is limited to 240mW so in fact what you can get is 23.8dB. It is still extremely loud volume level (107.3dB) but more important it shows specific limitation - output current limit. And it is something that might appear as problem with driving some low impedance and extremely low sensitivity headphones. You can face it also doing EQ of headphones by boosting low bass as this might require extra dB comparing to reference 1kHz area. So these 25dB of amplification will not be used for reaching 108dB of general volume but for providing power to correct shortcomings in bass area.
Looking at specs of TINHIFI P1 MAX that were the starting point for this discussion - they are 16 Ohm and 98dB/1mW. Even with SE output of Q5k we can get 19dB (80mW) of amplification. And looking at P1 frequency characteristics that shouldn't be problem even with the lowest bass (EQ). But I can imagine that driving them directly from 3.5mm output from smartphone (or other small portable device) might be more "challenging" due to its low impedance.
Concluding. Q5k is quite powerful for both - high impedance (4V at balanced output) and low impedance (80/240mW SE/BAL) phones. But we can find some "special" cases where we might face one of its limit - voltage or current...

Yeah.
I've tried HE6seV2 using Qudelix.
Sound is compressed.
No headroom.
Barely enough volume for streaming tracks.
Actually it seems the headphones are defective compared to my speaker amp (one would hope so, but still).
So don't say volume is enough.
That's misinformation.

 

[3fifty]

Yeah.
I've tried HE6seV2 using Qudelix.
Sound is compressed.
No headroom.
Barely enough volume for streaming tracks.
Actually it seems the headphones are defective compared to my speaker amp (one would hope so, but still).
So don't say volume is enough.
That's misinformation.

Can you please explain what you mean by lack of headroom?

Audible compression would be easily measurable, right?

 

[Guipnox]

Can you please explain what you mean by lack of headroom?

Audible compression would be easily measurable, right?

Not enough volume for quiet tracks or not-overly-compressed tracks.

I don't know.
All I know is what I heard.
And it was the sound all compressed at the level of my eyes. No height.
Using my speaker amp opened the stage and made the sound insanely dynamic.
You never know till you hear it.
Even a Drop THX can't properly power a HE6seV2. Imagine Qudelix LOL