Addicted to Fun and Learning
- Dec 21, 2020
Hmmmm I get what you are saying, I was asking in reference to your measurements. I was considering purchasing a used Anthem amplifier so I can then have access to use 7 channels.Yes that is specific to your avr, speakers and your listening habits (spl requirement and distance).
To be clear, like power amp output, it can also be said that for preamp output, the higher the better. It is however, important to realize if you don't ever tap into outputs (preamp and/or power amp), you won't benefit from it in terms of audible sound quality. I only ever used about 0.2 to 0.5 WPC average, or up to 50 W (8 ohm) for the 20 dB peaks in some contents I might play when listening to music in stereo, but the amps I use are rated between 50 (the weakest one) to 350 W (the strongest one), not counting the 5 W DIY amp. I have used all of them to drive my speakers and they all perform the same sonically speaking with the exception of the 5 W amp.
The answer to your question about preamp output (aka pre out) voltage requirement depends on at least (in case I forgot some) the following:
- you power amp input "sensitivity", or "gain"
- your speaker sensitivity 2.83 V/m is preferred, if given in W/m then you have to consider the impedance, example for 4 ohm speakers, at the same voltage the power will be 2 W, and for 6 ohm speaker it will be 1.33 W
- your spl requirement, this is important when you consider the fact that for every 3 dB increase, your power amp requirement will be doubled and your preamp output voltage will have to increase by square root 2, that is about 1.414 times.
- your listening distance from speakers. Without factoring room gain, every time you double the distance the spl at you listening position will be reduced by 6 dB.
Assuming you don't sit further than say 4 meters, in a medium to medium large room, you will not have to worry about the above if you stick with preamp output >2 Vrms and power amp output > 200 W. Again, generally the higher the better..., there are always exception to the rules such as for someone who has truly hard to drive speakers..
Lastly, you seem to always referenced to "input sensitivity", from your previous posts/questions but I am not sure if you understand fully the relationship between "input sensitivity" and "gain".
In my opinion, gain is preferred because it is easier to understand. It is the ratio of Output to Input, the only slight complication is that amplifier gain is more often expressed in dB that is based on the "log scaled". The formula to convert from Vout/Vin in multiples to dB is 20X log (Vout/Vin).
Example: Vout/Vin = 2 would be the same as Vout/Vin = 20Xlog2 = 6 dB
People sometimes get confused (or even misled by, due to misconception) by the input sensitivity specification when it simply says 1.2 V (just an example), without any details. That 1.2 V could be based on achieving the rated output that can be anything such as 75 W, 100 W, 500 W etc.., or it is stated for a reference output of say 100 W into 8 ohms, as is often the case for Parasound amps.
The other potential confusion is due to the use of "low" or "high". Example, people may say 1 V is low, versus 2 V, because they are talking about the value, yet 1 V is actually higher than 2 V if they truly refer to "sensitivity" of the amp. To me, it would be more correct, and hopefully more common too, for people to refer to the sensitivity of the power amp, literally, than to refer to the input voltage value, so the lower the input voltage value in the spec would (and should) mean the higher sensitivity the power amp is.
So my question to you: when you said "a higher input sensitivity amp", did you mean the input voltage value, or the sensitivity (literally..)of the power amp? lol..
It says 1.5v for full power with a 29 db gain, MCA 525 gen 1 which is 225 pc.
Since the volts, db, and wattage is different does this change your original computation.
Also just briefly, I have not been into any type of audio until the pandemic. I bought my 7013, my first amp/equipment in September 20’, and I did not purchase my speakers until Black Friday 2020 so basically started using what I had in December so it’s been roughly a year and a half which is about the the time I signed up to ASR.