Thiel & Onkyo A-9755 - A safe match???

[Astirose]

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

[JohnMichael]

Welcome to AudioReview. I unlocked your thread so members can answer your questions.

[basite]

I'm thinking the amp would be able to drive them, but just not in such a big room...

10x10m is pretty big, so you'll have to turn up the volume quite a bit to fill the entire room I think...

I placed my Thiel CS2.3's in the living room (which is about 6m x 5m or so, but it's an open room on one side, so you could say it's like 6m by 12m or so) and I felt I could use slightly more power there, my amp didn't go in protection mode, but it did hit the 200 watt mark on the meters often...
more power is always welcome for thiels, but I think that if you want to achieve the best sound then, you should move to bigger speakers (a Thiel CS2.4, for example)...

Keep them spinning,
Bert.

[blackraven]

You should be fine with the A9755, it should have no problems driving those speakers to loud levels and it would be a great amp for moving up the speaker ladder in the future.