Oh how I wish Class D amps ...

" 'd' amps have a pretty good phase shift in the HF range due to the Zobel."

To the best of my knowledge no class D amplifier on Earth uses Zobel "filters". With Zobel, you would need to build up your amplifier individually to satisfy requirment of each individual speaker not to metion its other problem. It would be terrible creature....

All, with no exception, class D amplifiers have a challange in HF signal processing. Similar to that of traditional tube amplifiers in LF area and traditional transistor amplifiers in midrange.

Simon

Hello Kijanki,

I wish to apologize. I have had no idea whatsoever that ICE Power uses Zobel network. I don;t want my words to be iterpreted as even slightest critic of our competitor.

Still, for the record (and from our web site):

" Spectron designs team won a contact with pro audio giant Inter-m (among others in competition were Bang & Olafson and Philips)..."

Inter-M may be the biggest pro audio company and we are proud, as small team of 4 design & 1 production engineers, to have our design to win against somewhat more resoursful Philips and B&W ...but music lover have right to choose and be happy with any design they choose. Its a given.

If I offended someone - my deepest apologies again.

Regarding "There is no signal processing since most of class D amps are analog "..... before digital signal there was and still is analog signal which people for 100 years processed: from simplest as adding to most complex. Even computer does not need to be digital; some early computers were analog.... making my living for 30 years from digital signal processing I better know what I am talking about.

Respectfully,

Simon

Hello Kijanki,

"It is often said that Icepower sounds good only with linear power supplies. On the other hand newest linear class AB amps from Jeff Rowland (one costing $46k) use switching power supplies. "

You are correct, Jeff Rowland developed his own highly regulated switching power supplies with PFC and show that this power supplies is the future for class A or A/B, ss and tube amplifiers.

We also have developed in 2008, very powerful swtiching power supplies with PFC abd fully regulated but we use it in our pro audio projects only as price/benefit analyses of moving it to Musician III with its linear power supplies show relatively little sonic benefits versus substantial price increase to cover the transition.

Refarding all other switching power supplies I am aware of - some like NuForce in their Ref 18 amplifier started to add electrolitic energy storage capacitors, This, if done right, should substantially improve current delivery and peak power delivery which in turn should improve sound.

Kijanki,

I more or leass agree with you in your assessment of SMPS versus lienar power supplies and already noted that we use both, one type in audiophile products and another in pro audio projects (e.g. 8kw rms pro audio ampliifer with linear power supplies will need a truck to move from one place to another).

The only reason whyt we did not move SMPS to audiophule products is the cost. I think very few music lovers will be willing to pay additional , say $1k or $2k (I don;t remember exactly) for slight improvment in sound. Plus it would be bad for our reputation: to charge money and not deliver.

Regarding "What is different in Spectron amps? " - again from our web site:

"Uniqueness of the Spectron Design
====================================
Chief Designer John Ulrick is a control systems engineer (and an amplifier is a control system). Because of this, Spectron amplifiers are designed with an emphasis on very high speed control loops. These high speed control loops result in the amplifier’s remarkable ability to reproduce detail that other amplifier’s cannot reproduce. Moreover, due to this incredible control loop speed and stability, our amplifiers can drive the most difficult speakers in the world (down to a 0.1 Ohm load!) effortlessly. "

Simon