Which preamp for Symphonic Line Kraft amps?

Jonathan,

The Kraft amp has a 10K input impedance and a high sensitivity. In my experience (very limited), you need a preamp with a very low output impedance, moderate gain (12 db or so), and dead silent. I have a Kraft amp and RG3 MK4 preamp. I did own a ARC REF3 for a while but found it lacking in bass, dynamics and it had a low level hiss that was distracting at night. In the end I gave up and resigned myself to trying the SL preamps. I have tested both the tube SL preamp and now the RG3 MK4. Both do the job. I have also heard of many state side Kraft owners having excellent results with CAT preamps. I decided not to pursue this because the CAT can have too much gain and then you hit the noise problem.

Good luck in your search.

Jay

Jonathan,

600 Ohms may be too high. 100 Ohms is more like it. Remember the SL tube preamp has 100 Ohm ouptut impedance and the SL RG4 RG3 preamp has a 1 Ohm (not a typo) output impedance. If you had the opportunity to try the CAT, that would be ideal. Make sure the stepped attenuator does not provide too much gain and not enough resolution on the low end of the scale. Very few tubed preamps have low output impedance. In your case, it may not matter because the preamp drives the crossover. The crossover is responsible for driving the amp and that should be tested before purchase.

Dev,

My system is for CD playback only. I use a Marantz SA-11S2 player. Although the Kraft has a balanced input it is just connected single-ended inside. Hope that makes sense? So, when using the ARC Ref 3, you don't get the benefit of the 12 db of gain in balanced mode. Instead, you get 6db of gain, along with an output impedance that is too high to drive the Kraft amp.

The net of this is the sound lacks weight and hiss was intrusive at low level listening. At least that was my experience.

The ARC Ref 3 is a phenomenal product, but was not a optimal match with the Kraft amp for my ears. I reluctantly sold it.

I have no experience with Karan and cannot comment.

Good luck,

Jay

Dev,

The black finish is call "Aranya", which could be best described as a black chrome finish. The last I heard, SL does not offer this anymore for the Kraft amps due to the cost and difficulty in getting a consistent finish.

The amps are class "A", but probably a sliding bias system.

Driving my B&W 802D it never gets hot, just warm no matter how loud I play it. But, the temperature of the heatsinks would rise considerably if you were driving a tough load like a Apogee.

Jay