Astirose
04-17-2008, 01:57 AM
I desperately need advice -Thiel & Onkyo A-9755 - A safe match until I can upgrade -Any Suggestions? I've been without a stereo for about 10 weeks now and I need my fix! My little Bose portable is filling in for CD/DVD from the TV audio output at the moment.
Hi Everyone, I'm Astirose, a new member. I noticed Mr Peabody's comments on another thread about high current amplifiers that can power Dynaudio 52. I have a pair of 4 ohm Thiel cs1.6's which look similar in specs to the 52's and I also need a 2 ch amp.
A salesman recommended the A-9555 behind these speakers. I was really quite impressed with the sound - so much so it was hard to keep my mind on the paperwork - so I gave in and did something else quite mindless so I could enjoy the music.
My concern is that since my speakers have such a low impedance I didn't know if the A-9755 would be a safe combination - without risking damage to the amp or speakers.
After using the A-9555 for about a week it cut out when I had the volume up to 5 to 11 on a lower volume recording- a cd I hadn''t played with the Onkyo before. I didn't feel to push the amp so I occasionally nudged up the volume every now and then if it sounded safe to do so - Cautious, as I know I have very difficult speakers to drive and didn't want any damage to either amp or speakers. It sounded first like a needle scratching an LP and then the volume went low as though they were singing through a tunnel. Once I turned the amp off and on again everything was AOK. The amp had a safety/overload cut out. I had a gut feeling I needed the higher powered A-9755 rated at 300wpc at 4ohms which was not available at the time of my trialling the A-9555. I had also heard to be careful with an under powered amp as it could damage my speakers - is this right? We have a huge open plan living area, about 10x10m and I feel I need the higher powered A-9755 to fill this space at a decent volume without pushing an amp. The volume wasn't at blasting level so I'm not sure as the why the amp cut out - it couldn't deliver such a high current to my hungry speakers? Going by experience or the specs is there any other reason for this?
Thiel cs1.6
Description: Two-way, magnetically shielded, floorstanding loudspeaker. Drive-units: 1" (25mm) aluminum-dome tweeter, 6.5" (165mm) metal-cone woofer with 3" voice-coil. Crossover frequency: 3kHz. Crossover slopes: first-order, 6dB/octave. Frequency response: 50Hz-20kHz, ±2dB. Phase response: ±10 degrees maximum. Sensitivity: 90dB/W/m. Nominal impedance: 4 ohms, 3 ohms minimum. Recommended Power: 50-300W.
The Onkyo A-9755:
AMPLIFIER SECTION
Power Output .................................................. ...................................... 300 W/Ch (4 Ω, 1 kHz, JEITA)
Dynamic Power............................................. ........................................ 330 W + 330 W (3 Ω, Front)
270 W + 270 W (4 Ω, Front)
170 W + 170 W (8 Ω, Front)
Total Harmonic Distortion .................................................. ................ 0.08 %
Damping Factor .................................................. .................................. 25 (Front, 1 kHz, 8 Ω)
Input Sensitivity and Impedance
Phono MM .................................................. ........................................ 2.5 mV/50 kΩ
CD .................................................. .................................................. ... 200 mV/50 kΩ
Output Level and Impedance
Rec out............................................... ................................................. 200 mV/2.2 kΩ
Phono Overload.......................................... .......................................... 70 mV (MM, 1 kHz, 0.5 %)
Frequency Response .................................................. ......................... 10 Hz-60 kHz (+ 1, - 3 dB, CD)
Tone Control .................................................. ........................................ + 10 dB, - 10 dB, 100 Hz (BASS)
+ 10 dB, - 10 dB, 20 kHz (TREBLE)
+ 10 dB, 50 Hz (LOUDNESS)
+ 2 dB, 10 kHz (LOUDNESS)
Signal-to-Noise Ratio............................................. ............................. 100 dB (CD, IHF-A), 70 dB (Phono, IHF-A)
Speaker Impedance......................................... .................................... 4 Ω-16 Ω
I know my speakers can go as low as 3ohms but by the reviews so too can the Onkyo.
I am new to all these specifications and understand "a little" of what I need to look for. I was wondering if anyone had an opinion as to whether its worth trying the A-9755 and would they work safely together?
Cheers Astirose
Hi Everyone, I'm Astirose, a new member. I noticed Mr Peabody's comments on another thread about high current amplifiers that can power Dynaudio 52. I have a pair of 4 ohm Thiel cs1.6's which look similar in specs to the 52's and I also need a 2 ch amp.
A salesman recommended the A-9555 behind these speakers. I was really quite impressed with the sound - so much so it was hard to keep my mind on the paperwork - so I gave in and did something else quite mindless so I could enjoy the music.
My concern is that since my speakers have such a low impedance I didn't know if the A-9755 would be a safe combination - without risking damage to the amp or speakers.
After using the A-9555 for about a week it cut out when I had the volume up to 5 to 11 on a lower volume recording- a cd I hadn''t played with the Onkyo before. I didn't feel to push the amp so I occasionally nudged up the volume every now and then if it sounded safe to do so - Cautious, as I know I have very difficult speakers to drive and didn't want any damage to either amp or speakers. It sounded first like a needle scratching an LP and then the volume went low as though they were singing through a tunnel. Once I turned the amp off and on again everything was AOK. The amp had a safety/overload cut out. I had a gut feeling I needed the higher powered A-9755 rated at 300wpc at 4ohms which was not available at the time of my trialling the A-9555. I had also heard to be careful with an under powered amp as it could damage my speakers - is this right? We have a huge open plan living area, about 10x10m and I feel I need the higher powered A-9755 to fill this space at a decent volume without pushing an amp. The volume wasn't at blasting level so I'm not sure as the why the amp cut out - it couldn't deliver such a high current to my hungry speakers? Going by experience or the specs is there any other reason for this?
Thiel cs1.6
Description: Two-way, magnetically shielded, floorstanding loudspeaker. Drive-units: 1" (25mm) aluminum-dome tweeter, 6.5" (165mm) metal-cone woofer with 3" voice-coil. Crossover frequency: 3kHz. Crossover slopes: first-order, 6dB/octave. Frequency response: 50Hz-20kHz, ±2dB. Phase response: ±10 degrees maximum. Sensitivity: 90dB/W/m. Nominal impedance: 4 ohms, 3 ohms minimum. Recommended Power: 50-300W.
The Onkyo A-9755:
AMPLIFIER SECTION
Power Output .................................................. ...................................... 300 W/Ch (4 Ω, 1 kHz, JEITA)
Dynamic Power............................................. ........................................ 330 W + 330 W (3 Ω, Front)
270 W + 270 W (4 Ω, Front)
170 W + 170 W (8 Ω, Front)
Total Harmonic Distortion .................................................. ................ 0.08 %
Damping Factor .................................................. .................................. 25 (Front, 1 kHz, 8 Ω)
Input Sensitivity and Impedance
Phono MM .................................................. ........................................ 2.5 mV/50 kΩ
CD .................................................. .................................................. ... 200 mV/50 kΩ
Output Level and Impedance
Rec out............................................... ................................................. 200 mV/2.2 kΩ
Phono Overload.......................................... .......................................... 70 mV (MM, 1 kHz, 0.5 %)
Frequency Response .................................................. ......................... 10 Hz-60 kHz (+ 1, - 3 dB, CD)
Tone Control .................................................. ........................................ + 10 dB, - 10 dB, 100 Hz (BASS)
+ 10 dB, - 10 dB, 20 kHz (TREBLE)
+ 10 dB, 50 Hz (LOUDNESS)
+ 2 dB, 10 kHz (LOUDNESS)
Signal-to-Noise Ratio............................................. ............................. 100 dB (CD, IHF-A), 70 dB (Phono, IHF-A)
Speaker Impedance......................................... .................................... 4 Ω-16 Ω
I know my speakers can go as low as 3ohms but by the reviews so too can the Onkyo.
I am new to all these specifications and understand "a little" of what I need to look for. I was wondering if anyone had an opinion as to whether its worth trying the A-9755 and would they work safely together?
Cheers Astirose