ICEpower 1200AS2 question

[Lau]

Hello ASR!

I have bought a 1200AS2 after watching Guntars Smits compelling youtube video and looking at the funds available for HiFi. I drive it with a Bluesound Node X and to me the sound quality is very good. So far so good! However, I am a bit underwhelmed with regards to power. According to the data sheet it should output around 600W in 4 or 8 Ohm. but I can crank the volume on the bluesound to the max without stressing the speakers (Dali rubicon LCR)?

In the 1200AS2 data sheet it says "Audio inputs voltage" +/- 8V. Does that mean that the 1200AS2 need +/- 8V to reach full output? In that case I get why the +/- 2V output from the Node doesn't stress the system. Would I have to add a mini preamp in front of the 1200AS2 input in order to utilize the power of the board and if so... what to choose?

I hope copy/paste works

BR
Morten

 

[Ze Frog]

Do you have adjustable gain on input?

Most amps the spec for maximum will be at maximum gain with a specific input voltage. Instead of a Pre-amp you can use a DAC.

 

[StigErik]

Look under 7.1 in the datasheet.

Your 2V source yields 39V output, which is 39^2 / 8 = 190W in 8 ohms.

 

[staticV3]

Does that mean that the 1200AS2 need +/- 8V to reach full output?

The 1200AS2 has a gain of 25.8dB and a maximum output power of 700W at 4Ω/620W at 8Ω (both at 230V mains).

That means that the required input voltage to clip the output is sqrt(700*4)*10^(-25.8/20)=2.71Vrms for 4Ω and sqrt(620*8)*10^(-25.8/20)=3.61Vrms for 8Ω.

25.8 dB equals a gain of 19.5 times. But that is with balanced signal, and you don't have that on your source.

Your 2V source will effectively be 1V

The 1200AS2 has differential inputs, which means that it does not matter if the input signal itself is differential or single ended.
A 2V source will be 2V, regardless of whether it's SE or Bal.

 

[EdW]

The +/-8V is the absolute maximum signal that may be applied to the input. Outside this the input protection diodes (for ESD protection) will clamp hard and prevent damage. +/-8V is not a recommended use condition!

 

[StigErik]

The 1200AS2 has differential inputs, which means that it does not matter if the input signal itself is differential or single ended.
A 2V source will be 2V, regardless of whether it's SE or Bal.
View attachment 357279

Yes, that is correct. I will edit my original post.

 

[Sokel]

Look lower at the specs,what you posted is the clamp voltage.
What you seek for is here:

(that's for using it mono of course,which you can with both versions,either 1200as2 or 1200as1 )

 

[Lau]

Cheers guys - ASR rocks!
Seems like Im only getting 2/5 of the power out of the IcePower 1200 board
Is there a quality input buffer I could add to the system in order to increase the signal from 2 to 4V?
I found this one: https://www.audiophonics.fr/en/prea...tereo-buffer-module-opa-op275-v22-p-4227.html But is there a better alternative out there?

 

[staticV3]

Cheers guys - ASR rocks!
Seems like Im only getting 2/5 of the power out of the IcePower 1200 board
Is there a quality input buffer I could add to the system in order to increase the signal from 2 to 4V?
I found this one: https://www.audiophonics.fr/en/prea...tereo-buffer-module-opa-op275-v22-p-4227.html But is there a better alternative out there?

The Node X has a maximum output voltage of 2.1V

That will limit output power to 420W at 4Ω and 210W at 8Ω.

In other terms, 3/5 of max at 4Ω and 1/3 of max at 8Ω.

However, loudness (what we actually care about) doesn't scale linearly with power.

In terms of loudness, the Node X is enough for 85% of max at 4Ω and 70% of max at 8Ω.

If you're absolutely sure that you're getting the full 2.1V out of the Node X (check with a multimeter!), and it's still not enough, then you could use an external Preamp between the Node X and your 1200AS2 to get that last 15/30% of volume.

 

[mocenigo]

Cheers guys - ASR rocks!
Seems like Im only getting 2/5 of the power out of the IcePower 1200 board
Is there a quality input buffer I could add to the system in order to increase the signal from 2 to 4V?
I found this one: https://www.audiophonics.fr/en/prea...tereo-buffer-module-opa-op275-v22-p-4227.html But is there a better alternative out there?

If that thing can be configured for 12dB gain, then you could add it just as a simple buffer, in a little box with a potted and shielded transformer, and just in and out. You can ask Audiophonics whether they can put other opamps, if you want objectively better performance. They can probably send you a complete kit to be assembled. Just make sure you are not maxxing the volume out of the Node. Maybe 6dB is also sufficient for your needs.

You could otherwise just buy a Topping A50S, but I do not know what is its max gain as a preamp. Same for L30II.

 

[staticV3]

You could otherwise just buy a Topping A50S, but I do not know what is its max gain as a preamp. Same for L30II.

All specs are on Topping's website, including max preamp gain.

 

[mocenigo]

All specs are on Topping's website, including max preamp gain.

Ahha, it’s been quite some time that I haven’t had a look at those sites because there is more than one site: one outdated and abandoned, and one that is very slow.
0/6dB (selectable) for the A50s
and -14/0/16dB (also selectable) for the L30II.