Help with Max desired power from amplifier

[adLuke]

Hello all,
I have a simple question (I think) to which I have not been able to find a simple answer.
I have to change my amplifier and need to restrict the choice to those amps that will allow me to hear at my desired sound pressure level, in my listening environment.
My current amp is an AVR Yamaha RX-Z9, rated at 170w per channel into 6 Ohm and 250w peak power (Japanese model).
My speakers are (rare) JBL Ti6k (front, rated 90db, 6Ohms nominal), Ti2k (surround, rated 88db, 8Ohms nominal), Tik Center (center channel, rated 88db, 6Ohms nominal) in a 5.0 setup.
I know that for my listening, I like to keep the volume at -10db for full-on sessions. Rarely I find myself in the mood to push to -6/-5db but usually for very short moments.
I would happily give up the ability to push to sound levels like those I experience with -6/-5 db on the Yamaha scale.

Now my question is: can I figure out what power should I aim for without actually having to listen to the actual amplifier?
Is it as simple as working back the power from 170w considering I can reduce by 10db from its maximum power?
So approximating, every 3db I can half the power: considering only 9db I could take a power 8 times lower than 170w, so 22w per channel into 6ohms should be enough?
Is this completely off? Are there any simple measurement I can do to make sure I am not off the mark completely?

Thanks everyone for their input.

PS: I am not sure if this should be put in the general discussion instead of here?

 

[Sokel]

There are lots of online calculators for this.
What you have to add is any potential need for EQ/RC and 15-20db headroom above your average listening level for worst case peaks.

 

[adLuke]

Thanks Sokel, the online calculators I found take power, sensitivity and distance as inputs to give you a certain output SPL in decibels.

The thing is that all host of other factors (including those you mentioned: EQ, headroom for dynamic range) enter into the equation.
I was hoping that by knowing the exact listening preferences (i.e. -10db on my Yamaha amplifier) I could get a more precise assessment.
Thanks

 

[Sokel]

The -10db from your Yamaha can mean a lot of things and nothing.
The stated 170 watt from your Yamaha can as well be actual,continuous,dynamic,peak,etc power.

You must also consider the gain of any new amp as it may not be the same as the Yami's.
Do you want to replace all channels or the front 3 for example?

 

[adLuke]

I guessed it would be more complicated.
I will need to replace all channels.
Where would I find the info needed like the gain in my Yamaha Amp? Any aka names?
I can't seem to find that info on the very detailed maintenance manual.
Thx again

 

[Sokel]

I guessed it would be more complicated.
I will need to replace all channels.
Where would I find the info needed like the gain in my Yamaha Amp? Any aka names?
I can't seem to find that info on the very detailed maintenance manual.
Thx again

By the numbers I saw around gain must be around 26db,pretty standard.
There's lots of power in there as I saw,so if you want to get more you have to aim pretty high,to power amps that can give a lot more than 300 watt per channel so you can have a substantial difference.

Good news is that it seems that it's preamp can output enough voltage to drive most of the power amps to full output and it's also clean unlike lower end receivers.

There's an Audioholics 02.21.08 issue article with measurements and other useful stuff to use.

 

[adLuke]

oh I think I was not clear, sorry.
I am not looking at getting more power. I believe I am not even using Yamaha full power. I set the volume well below the maximum (by 10db usually).
As I need to move away from this amp I was trying to figure out what is the minimum I can get away with while still keeping my preference for sound pressure unchanged. There are so many Calss D amp now I can choose and I would like to know if (for example) a Topping PA5 II would push my speakers hard enough for me to enjoy.
Hope this clarifies.
Thanks for your input.

 

[Schollaudio]

The -10db from your Yamaha can mean a lot of things and nothing.
The stated 170 watt from your Yamaha can as well be actual,continuous,dynamic,peak,etc power.

You must also consider the gain of any new amp as it may not be the same as the Yami's.
Do you want to replace all channels or the front 3 for example?

True. I can be helpful to find someone with an oscilloscope and look at peak voltage and sort of eyeball music voltages below peak. Then guestimate the power requirements for the level wanted. I know vague nonsense. It's hard to really know what power an amp is producing. I like amps with +-60V rails or more and adequate power supplies to maintain that voltage. That's 200 watts at clipping which with decent recordings is about 20 watts for most of the signal.

 

[adLuke]

Ok thanks.
So if I understand correctly the info I currently have is not very useful (I could use any spl calculator to get the same results) and the math I did is completely useless.
That is a shame as I was hoping to be able to use the new crop of TypeD amp (Topping/Aiyima/Fosi): I saw Amir being amazed at the result he got from the little Aiyima A07 Max with his big speakers (edit to his Aiyima A07 Max review). On paper my speakers are slightly more sensitive than the Revel Salon 2.
So I hoped I could get a few of those and push my speakers to my desired levels.
I guess I should look elsewhere then. For example, the Ice/Purifi/Ampex type amps that have a lot more power.
Thanks a lot for your input, much appreciated