Elberoth2
IMHO, the reasons for the mixed opinions on Icepower amps are the extent of RF present in a system, electrical isolation of the amp from the rest of the system, vibration isolation and impedance matching with the preamp.
Even the H20 with its linear power supply responds well to RF reduction measures. RF picked up by speaker cables can propogate backwards though the system. In the case of switching power supplies, there is potential to add more noise. I find that the Powerwraps are very effective at taming RF with the largest benefit on the player and preamp.
Power units that isolate the amp from other components are helpful.
For vibration control, isolate a module amp as you would a high quality front end component.
In the Rowland model reviewed by the TAS, a transformer is used to make preamp impedance matching less of an issue. The comments by TAS remind me of those made in ancient reviews of step up transformers for moving coil cartridges.
Once manufacturers consistently address this issues inside the amp, I believe that there will be little demand for traditional solid state designs.
At Dave Magnan's site he has many specific recommendations to improve the sound of Nuforce amps.
One advantage of the H20 is the roomy chassis. This means that there is room to add better bypass caps, replace the mediocre nickel plated binding posts, input connectors and improve the transformer damping. Not easy to do in small chassis amps or when the power supply is part of the module.
Bob
IMHO, the reasons for the mixed opinions on Icepower amps are the extent of RF present in a system, electrical isolation of the amp from the rest of the system, vibration isolation and impedance matching with the preamp.
Even the H20 with its linear power supply responds well to RF reduction measures. RF picked up by speaker cables can propogate backwards though the system. In the case of switching power supplies, there is potential to add more noise. I find that the Powerwraps are very effective at taming RF with the largest benefit on the player and preamp.
Power units that isolate the amp from other components are helpful.
For vibration control, isolate a module amp as you would a high quality front end component.
In the Rowland model reviewed by the TAS, a transformer is used to make preamp impedance matching less of an issue. The comments by TAS remind me of those made in ancient reviews of step up transformers for moving coil cartridges.
Once manufacturers consistently address this issues inside the amp, I believe that there will be little demand for traditional solid state designs.
At Dave Magnan's site he has many specific recommendations to improve the sound of Nuforce amps.
One advantage of the H20 is the roomy chassis. This means that there is room to add better bypass caps, replace the mediocre nickel plated binding posts, input connectors and improve the transformer damping. Not easy to do in small chassis amps or when the power supply is part of the module.
Bob