Help needed - driving a Karan poweramp direct from Directstream


#1

Hi, I’m hoping there are some cleverer and more experienced forum members who can answer this question…

I’m looking to replace my Gamut D200mk3 power amp with a Karan KAS400 or KAS600, driven via balanced connectors direct from my Directstream (no preamp). What I want to know is whether the input gain on the Karan is well matched to the DS, such that I can listen at volume ranges from low to fairly high.

My Gamut has adjustable input gain between 0 db and -14 db, but the Karan doesn’t appear to have that feature. Is anyone able to tell me from the amp spec below whether or not the units are well matched from a gain perspective?

  • Channel separated power supplies from a two 1200 VA toroidal power transformers
  • 132.000 mikroF filter bank and four stages of stabilization
  • Frequency response DC-300kHz +0,-3dB
  • Signal to Noise ratio better than -112 dB
  • Intermodulation distortion less than 0.03% at rated power into 8 Ohms
  • Pink noise min RMS Power 420/720 W into 8/4 Ohms
  • Dimensions 500x235x450 mm (19,7x9,25x13,4 inch) WxHxD
  • Net weight 54 kg
  • Input impedance 30 kilo Ohm on RCA as well as XLR inputs
  • Gain 28 dB
  • phase is not reversed when using RCA inputs

Many thanks,

Mike.


#2

What you need to look at is:

Input Impedance (30k slightly low, but probably ok)

Input Gain (28dB) - pretty high gain

and input sensitivity.

The last parameter seems missing. It is important to know the max voltage (V RMS) allowed on the amp inputs, however you might also derive some info from the source output impedance (normally <1k) and amp input impedance.


#3

Um, the output level is also going to depend on the efficiency of the attached speakers.


#4

Many thanks Frode. I’ve just been advised by the distributor that the max output voltage should be 2.5V and that the impedance should be less than 100ohms. So his advice is as long as I set the DAC output to high (100 ohm?) then it should be a good match.

Does that sound about right?

Thanks, Mike.


#5

Hi Eldrick, speakers are Dynaudio Confidence C1, specs as follows:

Sensitivity 2.83v/1 m - 85 db

Long term power handling 170 watt (4ohm)

Impedence (nominal) 4 ohm

Thanks,

Mike.


#6
EldRick said Um, the output level is also going to depend on the efficiency of the attached speakers.
Yes, but what I am referring to is gain structure and headroom issues. If you don't need to turn up the volume this helps for safeguarding enough headroom but there is always a flip side of the coin on misc. aspects. The DS can use the -20dB switch and volume may be rised to 106. This flexibility is a bonus when connecting directly.

#7
Mike Marks said Many thanks Frode. I've just been advised by the distributor that the max output voltage should be 2.5V and that the impedance should be less than 100ohms. So his advice is as long as I set the DAC output to high (100 ohm?) then it should be a good match.

Does that sound about right?

Thanks, Mike.


The right guy for confirming this is Ted (or Paul) but I would guess it is going to work well. I reckon the spec given is for single ended input.