ifi Zen CAN Review (Headphone Amp)

[Thorsten Loesch]

Those are some nice mods i might do on my own zen can.

I was wondering on the PSU mod, from getting a 6A to a modded supercapacitor bank how big is the difference?

If you have a 6A supply, you should be fine. SuperCapacitors are not magic. In my case they help using a low current PSU and have extra power for peaks.

Thor

 

[Thorsten Loesch]

I have to say, the subtle X-Bass on the Zen-Can amp is really excellent, it works so well with nearly all music and headphones, practically for me with the HD600 and Ananda.
In comparison, all other Bass boosts are way too strong for almost all music genres.

This 5V PSU may not be great at 10Amps but seems to do well at 5Amps.

https://Amazon.de/gp/product/B08SVX1TH5

A reviewer did some tests.

Not great at 5A either. I do not know it, no idea. Needs trying out.

Thor

 

[pioterd]

Not great at 5A either. I do not know it, no idea. Needs trying out.

With rather cheap impulse PSU I found (5V/6A, 85% efficiency,120mV maximum noise level, filter on the cable) I heard an elevated noise and some electrical squeaks when I just connected DAC and headphones, set gain +18db and turned volume all the way up (without music which would probably destroyed headphones and my ears then, just turned on everything, headphones connected to Can, K712pro). From around 13’o clock there was increasing noise. Even with “default” 5V/2.4A it can be heard but less. Is it only a matter of PSU or kind of consequence of the whole ZenCan construction?
I can’t hear any noise at “zero”, +6 and +12 gain settings.

 

[LaL]

With rather cheap impulse PSU I found (5V/6A, 85% efficiency,120mV maximum noise level, filter on the cable) I heard an elevated noise and some electrical squeaks when I just connected DAC and headphones, set gain +18db and turned volume all the way up (without music which would probably destroyed headphones and my ears then, just turned on everything, headphones connected to Can, K712pro). From around 13’o clock there was increasing noise. Even with “default” 5V/2.4A it can be heard but less. Is it only a matter of PSU or kind of consequence of the whole ZenCan construction?
I can’t hear any noise at “zero”, +6 and +12 gain settings.

On full gain(+18) with the hd600 or Ananda 8 o'clock is loud, 9 is too loud with pain starting.
I'd say 12 o'clock would be destructive.

 

[pioterd]

I'd say 12 o'clock would be destructive.

Yeah sure, on my headphones I use only unity ("zero") gain, but I was curious about noise at +18 - does it come from Can's electronics, or the reason is low quality PSU?

 

[cheapmessiah]

Yeah sure, on my headphones I use only unity ("zero") gain, but I was curious about noise at +18 - does it come from Can's electronics, or the reason is low quality PSU?

Are you using the balanced input?

 

[LaL]

Yeah sure, on my headphones I use only unity ("zero") gain, but I was curious about noise at +18 - does it come from Can's electronics, or the reason is low quality PSU?

Yes, it's the Amp, same with mine at +18, with max volume, a slight noise floor hiss at full gain extremes.
4 Volt Balanced input and 6V when switched to variable on my Zen-Dac.

 

[cheapmessiah]

If you havent done it yet, you guys should try to ground the amp, connect any RCA input or the 3.5mm to your computer, my zen can is very noisy when connected via balanced to and that solves the problem.

 

[Thorsten Loesch]

Yes, it's the Amp, same with mine at +18, with max volume, a slight noise floor hiss at full gain extremes.
4 Volt Balanced input and 6V when switched to variable on my Zen-Dac.

What do you expect?

If you increase gain, you increase noise by the same amount.

According to Amir in 0dB Gain the Zen Can is -111dB/V (that is output noise is 111dB (unweighted) below 1V. It also means as long as your headphone has 111dB/1V or less sensitivity, you will have 117dB peak SPL with this headphone and a digital source outputting 2V (SE) @ 0dBFS without any noise that is audible.

Trust me 117dB is LOUD.

So use > 0dB Gain only for headphones with < 111dB/1V sensitivity or if listening > 117dB peak.

The various gain settings are there to match headphones. The 18dB setting is for 600 Ohm AKG K240 Pro headphones. Most headphones out there work fine at 0dB or 6dB.

FWIW, the AKG K1000 is 86dB/1V and can be driven by the Zen Can (balanced) to 16V (+24dB/V) and will drive the K1000 to 110dB peak and will need a minimum gain of 12dB/18dB (SE/BAL). It's the kind of headphone that needs 18dB Gain.

And yes, the K1000 can be driven by the Zen Can if you give it a decent PSU.

As a simple rule, try to get sensible but not very loud listening levels with the volume control at around 12 O'Clock on the volume dial. This leaves around 20dB to turn up if desired.

Personally I tend to use even less gain, if in doubt, lower gain and turn up volume more.

Few amplifiers with similar noise specifications offer 18/24dB Gain (SE/BAL). So to compare noise set gain equal.

And set gain and volume to sensible levels. If you cannot unpause a paused track at the gain and volume setting you use without tearing off the headphones, cursing and waiting a few hours before you hearing returns to normal (if ever) then whatever noise you are hearing is meaningless.

Noise is only meaningful in the context to the actual signal or relatively to to the signal.

Thor

 

[pioterd]

you guys should try to ground the amp

Yes heard about it, but isn’t it a problem only when it is connected (input) using poor cables? When I connected it using very cheap cables with my PC audio output, even touching the Can would generate noise. When used better, stock cables and connected it to ZenDac, no more “touching noise”. But sure, I can connect some cable to one of case screws and ground it.

 

[Thorsten Loesch]

With rather cheap impulse PSU I found (5V/6A, 85% efficiency,120mV maximum noise level, filter on the cable) I heard an elevated noise and some electrical squeaks when I just connected DAC and headphones, set gain +18db and turned volume all the way up

Shortcircuit the inputs in this test to simulate a source. Otherwise the very high impedance input will literally fish noise out of the air. Including noise from the SMPS.

Many SMPS are marginally stable and often include audible idle tones that shift with load.

One thing to look at if there is any earth in the system. If there is no earth at all, the system will be more prone to picking up noise.

The same is also true if more than one earth in the system.

(without music which would probably destroyed headphones and my ears then, just turned on everything, headphones connected to Can, K712pro).

Indeed. It's kinda like complaining at the garage that your car makes noise when you drive at 120mph down a dirt road.

The answer will be "then don't do that"!

Even with “default” 5V/2.4A it can be heard but less.

Find a better PSU ASAP.

May I again recommend the Headfi thread where I cover such details?

https://www.head-fi.org/threads/sup...ucts-and-possibly-other-manufacturers.966163/

Is it only a matter of PSU or kind of consequence of the whole ZenCan construction?
I can’t hear any noise at “zero”, +6 and +12 gain settings.

It's a result of physics. More gain always increases noise and signal the same amount.

Thor

 

[pioterd]

So use > 0dB Gain only for headphones with < 111dB/1V sensitivity or if listening > 117dB peak.

Thank you Mr Loesch. My K612pro with rather mediocre/low sensitivity 101db/V goes well on 0dB gain with 2V input.
Is the current (mAmpers) which Can can provide dependent on gain level? Or is the gain level just correlated with voltage?

try to get sensible but not very loud listening levels with the volume control at around 12 O'Clock

With k712pro, 12 o’clock is sensible for me on 0dB gain only when the input is 1V (0.5V via LineIn 3.5mm). With fixed 2V input, I rarely go past 13-14 o’clock maximum, for calm music. Probably I don’t listen at very loud levels.

 

[pioterd]

Find a better PSU ASAP.

May I again recommend the Headfi thread where I cover such details?

Sure I will, better 5V/4A is on the way, should be enough for my use, for some time at least ;-) I already read headfi thread, thank you.

 

[Thorsten Loesch]

Thank you Mr Loesch. My K612pro with rather mediocre/low sensitivity 101db/V goes well on 0dB gain with 2V input.
Is the current (mAmpers) which Can can provide dependent on gain level? Or is the gain level just correlated with voltage?

Current limit is absolute the internal PSU, but unless you have 4A+ @ 5V (not 4.5V) available the internal PSU will not be the limit.

If neither internal and external PSU cause the output current to be limited, then current is determined by output voltage and load.

As gain limits potential output voltage and this limits in turn current there is a secondary link.

Also, current limit depends on using SE or BAL etc. It's a complex subject.

Put simple, in SE headphones of around 60 Ohm or more can be driven to full output with suitable gain settings. In balanced mode around 90 Ohm or higher can be driven to full output, if the external PSU permits it in both cases (the stock options do not).

Thor

 

[Thorsten Loesch]

Sure I will, better 5V/4A is on the way, should be enough for my use, for some time at least ;-) I already read headfi thread, thank you.

I strongly recommend linear power supplies. The reasons are spelled out over on HF.

Again most cooking grade SMPS are a very poor options for audio.

Thor

 

[LaL]

Yes heard about it, but isn’t it a problem only when it is connected (input) using poor cables? When I connected it using very cheap cables with my PC audio output, even touching the Can would generate noise. When used better, stock cables and connected it to ZenDac, no more “touching noise”. But sure, I can connect some cable to one of case screws and ground it.

Yep, same for me.
I had this problem with a cheap 4.4mm interconnect cable between the Dac and the Can amp, I still use this cheap cable but I have to bend it a certain way and it's fine if I don't move it

 

[LaL]

.

 

[Thorsten Loesch]

Is there more to the tuning of the Signature Zen-Dac than just the upgraded capacitors ? My PCB is version 2.1

Anything done with V2 Zens is outside my knowledge, at best I can look at pictures.

In principle the "Siggies" could use OPA1644 instead of OPA1679 and upgraded resistors in addition to the capacitors, but I think it might have been mentioned.

But to my best guess, other than different parts, Siggies and non are using the same schematics and actual PCB layouts.

Certainly the V1 Siggies did.

Thor

 

[LaL]

Anything done with V2 Zens is outside my knowledge, at best I can look at pictures.

In principle the "Siggies" could use OPA1644 instead of OPA1679 and upgraded resistors in addition to the capacitors, but I think it might have been mentioned.

But to my best guess, other than different parts, Siggies and non are using the same schematics and actual PCB layouts.

Certainly the V1 Siggies did.

Thor

It definitely has a less warm sound signature compared to the regular Zen-Dac V1 / V2, which sound exactly the same.

Signature PCB V2.1

 

[Thorsten Loesch]

It definitely has a less warm sound signature compared to the regular Zen-Dac V1 / V2, which sound exactly the same.

Signature PCB V2.1

Funny, this looks like the original 1.0 PCB with the U8 8-Core XMOS. So that's basically my original design.

Funny how it got to 2.1... From 1.0...

Thor