The Beresford Capella Headphone Amplifier

[Kit1cat]

Arrggh...I have no more outputs on my amplifier.

Looks like there will need to be a Caiman II+2 version released soon with two outputs. One output for the amp and the other to feed the Capella!

Could you not take the output from the DAC to the Capella input 2, then the output from the Capella to your amp?

[maxrob200]

IMHO, it would defeat the purpose of a high end DAC and Headphone amplifier.
I am trying to avoid extra connections, interconnects and the potential for signal degradation going through more circuitry.

[Xaval]

Stan, congrats on the new product. From a feature perspective, I think it's unparalled as well as more than affordable. It will be a hit for sure just in time for Xmas

[StanleyB]

IMHO, it would defeat the purpose of a high end DAC and Headphone amplifier.
I am trying to avoid extra connections, interconnects and the potential for signal degradation going through more circuitry.

I am using the Capella as a preamp between the Caiman and my amp. With the Caiman output set to the FIXED position, the Capella Gatorized amplification stage delivers a clean analogue signal that is near impossible to describe. It is close to a well designed valve stage, but without the valve distortion.

[Theadmans]

I am using the Capella as a preamp between the Caiman and my amp. With the Caiman output set to the FIXED position, the Capella Gatorized amplification stage delivers a clean analogue signal that is near impossible to describe. It is close to a well designed valve stage, but without the valve distortion.

...Hi Stan - interesting that you should say the Capella sounds like a valve stage. At the moment I run a heavily modified Musical Fidelity X10D valve buffer between my Bushmaster MKII and Creek 4330 Integrated Amp. Not a purist thing for sure but I like the sound of the combination.

I am keen on adding a Capella to my setup. However, I too was concerned about adding another volume control and set of RCA phono leads to my setup. Maybe from you are saying I could kick the X10D into touch and replace it with the Capella. Do you think I will still get the valve like sound from the Capella even though I am running it into an Integrated amp?

Another alternative would be for me to simply link the Capella onto the Tape Out sockets of my Creek Integrated. However, the music by this stage would have come from my SBT->Bushmaster->X10D->Creek Integrated->Capella. What do you think would be best as I want to maximise the sound quality not only through my headphones but also my speakers.

[StanleyB]

Hi Adam, the only sure fire way is to give it a try yourself. What I think doesn't really matter. How it sounds like is all that counts. The volume control on the Capella can be used as an input sensitivity matching device into the amp. That was part of its purpose. A lot of people have amps with the old 350mV sensitivity. The 2Vrms output from a CD player would swamp a 350mV input. So being able to adjust the signal level into an amp is not a bad idea.

[Theadmans]

Thanks Stan - that is an interesting point about level matching. I never seem to get much above a quarter to the hour on the Creek volume knob. The X10D adds a little gain as well. I have even thought of getting those Rothwell RCA plug thingies - but have heard some bad comments about them. I guess the Capella will allow me to use more of the volume knob

[electroid]

Will the new amp have enough headroom in watts to power current-hungry planar magnetic headphones.....
Audeze LCD-2.1 ( 60ohms / 4 watts headroom needed)
+
Fostex T50-RP modified ( 50 ohms / 1 Watt headroom needed) ...?

So, from 1 watt to 4 watts of volume headroom dial after biasing in vs the usual 20-300 mWatts of dynamic headphones range.

I'm assuming/hoping the new unique amp features/buttons/dialability can zone into the planar current draw requirements......

[StanleyB]

Hi Mike, the Capella works a bit different than that. You adjust the GAIN control to suit the different power requirement of different headphones. The Volume control is then used to adjust the output level of the sound that you hear. So you can get the volume control to produce a near identical output level for various position of the volume control dial independent of whatever the impedance of the headphone is.
I think that you are trying to figure out the use of the volume control on the Capella compared to the majority of headphone amp designs. The others don't have a gain control, so the volume control position varies with the headphone impedance if you want to hear the same level of output. In the Capella those two functions are separated.

The Capella can produce up to 500mA at 9V of output if required. You do the physics calculation to work out how many Watts that is . But that is used far more efficient than on other headphone amps with just a volume control, which is why you can run the Capella from a 12V battery pack if required. Most other headphone amps would be incapable of doing the same, partly because of the way they are designed and the amount of current they draw even under zero signal condition.

As for the Audeze: A customer of mine is an Audeze agent and has bought a Capella last week. Make of it what you will, but he hasn't complained yet that the Capella can't drive his cans .

[electroid]

Hi Mike, the Capella works a bit different than that. You adjust the GAIN control to suit the different power requirement of different headphones. The Volume control is then used to adjust the output level of the sound that you hear. So you can get the volume control to produce a near identical output level for various position of the volume control dial independent of whatever the impedance of the headphone is.
I think that you are trying to figure out the use of the volume control on the Capella compared to the majority of headphone amp designs. The others don't have a gain control, so the volume control position varies with the headphone impedance if you want to hear the same level of output. In the Capella those two functions are separated.

The Capella can produce up to 500mA at 9V of output if required. You do the physics calculation to work out how many Watts that is . But that is used far more efficient than on other headphone amps with just a volume control, which is why you can run the Capella from a 12V battery pack if required. Most other headphone amps would be incapable of doing the same, partly because of the way they are designed and the amount of current they draw even under zero signal condition.

As for the Audeze: A customer of mine is an Audeze agent and has bought a Capella last week. Make of it what you will, but he hasn't complained yet that the Capella can't drive his cans .

Thanks for the fast reply.

500mA with a 9V supply would be:
P = V * I
P = 9V * 0.5A
P = 4.5W

500mA with a 12V supply would be:
P = V * I
P = 12V * 0.5A
P = 6W