ATC scm 19 upgrade ??

I have HD650 and really I don´t want sell them

I doubth about speaker cable.

How do you connect your atc´s ? bi-wiring?
or single cable with his standard gold jumpers?
I use atlas hyper 3 single cable and jumping with yba cable

thanks guys

How do you connect your atc´s ? bi-wiring?

My passive 20's are the old kind with no biwire posts ('95 model). I run monster cable from the power amp to the binding post - no spades on either end but everything good and tight.

The reason I warn you about extreme volume attenuation is because if you listen close near field (0.5 meters sitting at a computer workstation) then you will get about 91 db SPL at for 1 watt from the speakers. If you listen at 65 db SPL then you are talking 2.5 milli-Watts to the speakers. If you source music is really good or excellent from a raw recording and uncompressed (say 60 db of dynamic range) then the lowest audible signal (in theory) is 2.5 nano-watts.

These signals are starting to get very small - you may be bumping into non-linearities of electronics and or speakers at these levels.

There should be attenuator trim pads or something like that go between your Avocet and Bel Canto S300. That way you can run things with the volume contro at 2 O'clock instead of 8 or 9 O'clock.

Sorry if this is all ho-hum to you as you know all this already.

Hi shadome
very helping post
I´ll search any xlr attenuator for that.
After all this I think my jumper are very crappy thing.
I put the standar gold of atc and big ddiffference..
Someone advice me about zu ibis jumpers.

BTW Powerestudio. How long have you had them? Maybe they have yet to fully burn in yet? Cos it takes quite a bit of run in for the bass to fill in for the ATCs. Also something you should know is that high power output amplifiers don't do so good at low volumes, mainly being the greater presence in distortion levels at low levels than mid levels. Also Iceamps actually performs best powering lower impedance loudspeakers (<4ohm) than the usual 8ohms loudspeakers. Maybe try switching to an affordable Class A amp instead since you don't really need all that digital power at your disposal.

Wonderful_electric,

That is also a good suggestion - certainly it woudl be easy to borrow another amp and test again at these low levels even a 20 watt amp would be more than enough. In "theory" Class A is better at very low volume levels. That is how my ATC amps in the amp pack run - Class A to 2/3 power. In practice, most Class AB can do very well - some would say indistinguishable given good quality. I am not sure if Class D has established a reputation one way or the other but in "theory" it should be good too (provided the ultra-high frequencies are all filtered out and nothing gets into the audible band - kind of the same issue as with a DAC). Class D, in "theory", should be capable of producing exceptional linearity - just like digital. Since I have no hands on experience of Class D I really can't comment - but several people on Audiogon have spoken positively about this type amp (based on B&O design I believe)