Caiman as Headphone amp, very low?

[M.Gjøl]

Evening all.
I need abit help with the sound level when i use my new Caiman+ as headphone amp.¨
I have todays just recieved my superlux hd 681 headphones (32ohms)

But when i plug em into the dac there is very low sound, only if i turn the dac and ipad to max i can hear there is music, but cant hear what.
But when i turn on my amplifier i can hear the music.
Shall it be that way? I cant understand there is no / nearly no sound when my amplifier i shut off, there should´nt be any signal to it, or?


My setup: from Airport express to Caiman (gatorized) optical connection
From the dacs fixed output to my Vincent amplifier. RCA connection
From the Dacs front port to my headphones

But it dosnt work without my amplifier turned on.

Hope some of you guys can give me a answer.

Best Regards
martin

[Reid Malenfant]

Try unplugging the output to the amp & then see if you can use the headphones plugged into the DAC ;)

E2A:- Perhaps I should explain why this may well make a big difference... With the amplifier off or another input selected the input from your DAC may well be shorted to ground. The idea behind this is that you get no noise input from an unused connection.

The effect on the DAC will be to short the output & you'll get little or no volume out of the headphones :eyebrows:

[M.Gjøl]

Hey Reid.
It did work, so thanks a lot for so fast reply!
But, is there anything I can do so I don't need to turn my amplifier on or take out the cables?

[Reid Malenfant]

Well I'm assuming you are using the variable output to power your amplifier & the volume control on the Beresford DAC for system volume.

In reality there is nothing you can do, unless you do a bit of DIY or install some kind of switch box between the DAC & amp. You see, you need to disconnect the output to the amp as you have just discovered, glad it worked by the way :)

[M.Gjøl]

Infact I'm using the fixed output on the caiman, should I use the variable?

[Reid Malenfant]

Infact I'm using the fixed output on the caiman, should I use the variable?
Oh :confused: I'm really surprised that using the fixed output is resulting in the very same thing :scratch:

You see as far as I know they use different output stages on the Gator PCB, though I could be wrong. I thought the fixed output uses the single ended class A stage, while the variable output uses an op-amp. You'd be using the variable output to power headphones directly from the DAC, so I'm not sure what the heck is going on :scratch:

Sorry... All I can tell you though is you need to break the connection of the centre conductor (the screen doesn't matter) of the cables running to your amp. This could be done with a very small box & a switch, or a switch box for phono connections.

[M.Gjøl]

Will such a switch damage the sound signal?

[Reid Malenfant]

Will such a switch damage the sound signal?
Well you could argue the toss & say yes :eyebrows: However the resistance of such a switch would be so low as you might as well forget it's there compared to the source & what it's feeding ;) So as long as it was adequately screened I doubt you'd ever detect a difference.

Other than the fact your headphones would work with the DAC that is :lol:

[technobear]

I seem to recall one or two others have had this same issue. It's a bad way to design an amplifier because it could surely damage the source component. I think these amp manufacturers need to be named and shamed for their stupidity.