Beresford TC-7534 Caiman MKII line out voltage at variable out?

[Sabaselfsit]

This might be a dumb question. But it is written in the specifications that the Caiman MKII has line out voltage of 2Vrms. I understand that this is the case when it is set to fixed mode, and it send a continuous 2 volt signal to for example a pre-amp through the rca output, just lik a cd-player would do.

But what is happening when you actually use the Caiman MKII as a pre-amp and connect it directly to the power amp having it set to variable? Does it then alter the output voltage as you turn the voume on the dac up? So approximately at half volum it gives out 1Vrms...and at full volume it sends the maxium of 2Vrms out though the rca output? Or how does the volume control work when it comes to output signal?

What about the ohm value at minium and maxium volume?

I am asking in connection to power amp matching and input sensitivity.

[HighFidelityGuy]

Hi,

2Vrms is the maximum output voltage. The actual output voltage will be fluctuating all the time with the audio signal.
You don't need to worry about what the voltage is. 2V is the standard maximum for most consumer grade audio equipment.

When using the variable output option the maximum output voltage will be reduced when the volume control is set to anything other than full volume but that's just the way that volume controls work.

I believe the minimum output impedance of the Caiman mkII is 1Kohm. So that's probably what it will be when the output is set to fixed. When set to variable, the output impedance may be different depending on where the volume control is set as that's how many devices with variable outputs work. However I can't be sure about that and Mr Beresford is the only person who could confirm that. Either way it doesn't really matter.

As far as I understand it the Bushmaster mkII and Caiman mkII have no buffer circuit on their output which many DACs have to give them a lower output impedance. The benefit of not having a buffer circuit is that there's less circuitry in the signal path and so you get a cleaner sound. The downside is that you get a slightly higher output impedance. At 1Kohm the Caiman mkII has a slightly high output impedance. So I would recommend pairing it with an amplifier that has a fairly high input impedance of 50Kohm or above, especially if you need to use a cable longer than 1M between the two. Try to use a low capacitance cable if you can as that will help.

With that being said I currently use my Bushmaster mkII with a passive "preamp" that only has a 10Kohm input impedance and it sounds excellent. I use a 50cm Mark Grant G1000HD between the two.

I hope that helps.

[Sabaselfsit]

Hi Dave.

Thanks, that comes pretty well together with what I was thinking.

I connect the dac to a Technics SH-8055 eq using 0,5 meter Atlas Element Integra asymmetrical cable, from the eq I use 0,75 meter Atlas Element Integra asymmetrical cable to two NAD C275BEE power amps.

They have Input Sensitivity 1,2V (ref. rated power). And Input impedance (Fixed IN) 10 kΩ + 200 pF, and Input impedance (Variable IN) 100 kΩ + 100 pF.

I feel that using the fixed in on the amps (10 kΩ just like you) gives very hight volume very early on the travel of the volume control. So I used the fixed in on the amps and turn the knob to about -6db on the scale on their back. It gives a more comfortable range on the volume control.

But are little lost when it comes to calculating if this leave enough voltage for the amps to reach full power. Not that is matters, it get's loud enough and things start falling off the walls if I crank it..but still, hence the question about output voltage.

[HighFidelityGuy]

No probs.

I wouldn't worry too much about your amps reaching full power. You seem to be able to get adequate volume and seen as your DAC can output more voltage than your amps can cope with, you will probably still get full power from them even if you turn them down quite a bit. I think using the variable mode on your amps is the right way to go with your setup as it will allow you to match your DAC output to the amps input. I would recommend that you try to make it so that when the Caiman volume control is at approx 50%, you're getting the maximum volume you like to listen at with loud music. Volume controls usually sound best at around 50%.

Also, seen as you're using EQ, don't forget to try and avoid boosting any frequencies, especially below about 250Hz as that will stress your amps and make them more likely to distort.

Happy listening.