americanaudiophile :
You can always go higher in impedance.
The real problem is that the z906 isn't made to work with a receiver.
It has it's own processing and amps built in.
The Sony doesn't have 5.1 line level outputs or digital output.
You can replace the complete Sony HTS with the Logitech but to use them both you would need 3 speaker to line level converters. Not worth the aggro of having multiple controls interacting.
I suggest either get new passive speakers for the HTS, replace the entire HTS with a new one, or just using the Logitech by itself.
Thank you so much for your response, However i have brought the Logitech z906 (only speaker used) i would like to replace with sony HT, Kindly check the specs given below where i have found from the manual, Both the impedance and watts output have enclosed in that please go through it and advice me.
Logitech Z906 Performance specifications
• Total watts (RMS): 500 watts
- Subwoofer: 165 watts (6 ohms, at 52 Hz, at 10% THD)
- Satellites: 335 watts RMS (5 x 67 watts per channel {4 ohms at 3.85kHz, at 10% THD})
• Maximum SPL: >110 dBC
• Frequency response: 35 Hz – 20 KHz
• Amplifier: Ultra Efficient Class D
• Input Impedance: 8,000 ohms, min
• Signal to Noise ratio, A-weighted: >95dB
Sony IV 300 Specifications
Amplifier Section
POWER OUTPUT (rated)
Front L/Front R:
75W + 75W (at 3 ohms, 1kHz, 1% THD)
POWER OUTPUT (reference)
Front L/Front R/Surround L/Surround R:
125 W (per channel at 3 ohms, 1 kHz)
Center:
250 W (at 6 ohms, 1 kHz)
Subwoofer:
250 W (at 6 ohms, 80 Hz)
Inputs (Analog)
AUDIO IN
Sensitivity: 1.6 V/500 mV