Pre-amp vs poweramp

[Hessel Visser]

Hey y'all!
At the moment, at my ever changing set-up, there are 2 Tannoy Revolution XT6F's, the JBL Professional LSR310 active subwoofer, a Rotel RB1552 mk2, a Yamaha RXV6A, with a source being my pc mainly.
I use it mostly in 2.1 and using the Steinberg UR28M as the audio interface/dac, so the yamaha gets a analog signal.

Now, i am kinda obsessed with upgrading this system at least by the month(it started last summer with 2 jamo studio 180's and a Yamaha AS201)
Now i ve got my eyes on 2 new Emotiva XPA HC1's, but dont have real life experience with them. I can get the pair for €1550.
But now someone adviced me that i can get more improvement by getting a balanced 2 channel preamp to replace the Yamaha.

What are you guys' experiences and feelings on this one?
Probably i will have 'em all over time, but what to do first?

Have a good one!
Hessel

 

[MalVeauX]

Hi,

I'm curious what you need for HC1's for. Sounds like you're crossing over with a sub, unless I'm mistaken, so unless you have an incredibly huge room and you're sitting very far away from the mains, you don't need that kind of power to hit high listening levels. Since your source is mainly your PC, then all the media is digital, so it's not going to really do anything to then add something to go from digital to analog back to digital back to analog, etc, increasing the pathway and putting more things in there that are not needed. So if you're using the UR28M as a DAC and outputting analog level to your AXV6A receiver, unless you're using Direct mode or another passthrough system to avoid your AVR having any processing or bass management applied (including room correction), then you're likely processing the signal twice, and there's really no reason to use the UR28M as a DAC when your receiver is also a DAC and both being used. But if you're using your receiver as a passthrough amplifier, then that is a little different (but pretty much makes the need of having the receiver completely moot). But maybe this is why you're looking to go to two mono blocks? Do you need that kind of power? Or is this just a fun spending thing (nothing wrong with this, same logic as souped up fast cars, etc)?

You may want to share your room size, listening distance, any treatment you've done to the room, any measurements you have, etc, instead of buying 1.5k€ worth of amplification.

What is the end game goal? Trying to build a 2 channel analog system?

Very best,

 

[Hessel Visser]

Hi,

I'm curious what you need for HC1's for. Sounds like you're crossing over with a sub, unless I'm mistaken, so unless you have an incredibly huge room and you're sitting very far away from the mains, you don't need that kind of power to hit high listening levels. Since your source is mainly your PC, then all the media is digital, so it's not going to really do anything to then add something to go from digital to analog back to digital back to analog, etc, increasing the pathway and putting more things in there that are not needed. So if you're using the UR28M as a DAC and outputting analog level to your AXV6A receiver, unless you're using Direct mode or another passthrough system to avoid your AVR having any processing or bass management applied (including room correction), then you're likely processing the signal twice, and there's really no reason to use the UR28M as a DAC when your receiver is also a DAC and both being used. But if you're using your receiver as a passthrough amplifier, then that is a little different (but pretty much makes the need of having the receiver completely moot). But maybe this is why you're looking to go to two mono blocks? Do you need that kind of power? Or is this just a fun spending thing (nothing wrong with this, same logic as souped up fast cars, etc)?

You may want to share your room size, listening distance, any treatment you've done to the room, any measurements you have, etc, instead of buying 1.5k€ worth of amplification.

What is the end game goal? Trying to build a 2 channel analog system?

Very best,

Thanks for the reply,

The main goal is better sound quality!
I come from recordingstudio sound, thats my hobby for over a long time.. Hifi stuff just started last summer.
So my room at this point is small and is used as home cinema, homestudio and just as music listening/chillroom.
So the Yamaha is hooked up as 5.1 when i play movie(sound goes over HDMI(digital) to Yamaha) and automatically switches to 2.1 when music is played(sound goes to the UR28M and comes analog at the Yamaha).
So when i recently added the Rotel to the pre out on the Yamaha receiver i had a pretty big move forward in soundquality, like how many detailed background sound came more up front.. So im pretty sure theres way more to gain compared to the Rotel amp, and thats what i expect to get with the Emotiva's...
I think it already sound as good as a pretty good mastering studio already, but i guess it can always get better.

The converter in the Steinberg UR28M sounds WAAAAAAY better then the one in the Yamaha RXV6A.
The crossover is set on the Yamaha receiver, but it's possible to use the one on the subwoofer.
I could take a balanced line from the UR28m to the LSR310 and then hook up the Rotel to the LSR310 via XLR and set the x-over on the sub.

The room is about 10x10 ft and is stone wall and carpet floor. It's medium soundproofed in the mid-range frequencies( 600hz-3000hz ish), by ear..
I have been in a few rooms and studios in Europe and the US to compare, but the room sounds better that it should, but i have been experimenting alot with speaker placement across the room..
A larger room will sound better, but that would be because of coloration the room will add to the sound.

Only bass management i have going on on the Yamaha is x-over @80hz. all sound effects are off, only output levels for the individual speakers is set on the Yamaha.
And at the end of the line, i think monoblocks will also look pretty nice in my room, haha

 

[PENG]

Thanks for the reply,

The main goal is better sound quality!
I come from recordingstudio sound, thats my hobby for over a long time.. Hifi stuff just started last summer.
So my room at this point is small and is used as home cinema, homestudio and just as music listening/chillroom.
So the Yamaha is hooked up as 5.1 when i play movie(sound goes over HDMI(digital) to Yamaha) and automatically switches to 2.1 when music is played(sound goes to the UR28M and comes analog at the Yamaha).
So when i recently added the Rotel to the pre out on the Yamaha receiver i had a pretty big move forward in soundquality, like how many detailed background sound came more up front.. So im pretty sure theres way more to gain compared to the Rotel amp, and thats what i expect to get with the Emotiva's...
I think it already sound as good as a pretty good mastering studio already, but i guess it can always get better.

The converter in the Steinberg UR28M sounds WAAAAAAY better then the one in the Yamaha RXV6A.
The crossover is set on the Yamaha receiver, but it's possible to use the one on the subwoofer.
I could take a balanced line from the UR28m to the LSR310 and then hook up the Rotel to the LSR310 via XLR and set the x-over on the sub.

The room is about 10x10 ft and is stone wall and carpet floor. It's medium soundproofed in the mid-range frequencies( 600hz-3000hz ish), by ear..
I have been in a few rooms and studios in Europe and the US to compare, but the room sounds better that it should, but i have been experimenting alot with speaker placement across the room..
A larger room will sound better, but that would be because of coloration the room will add to the sound.

Only bass management i have going on on the Yamaha is x-over @80hz. all sound effects are off, only output levels for the individual speakers is set on the Yamaha.
And at the end of the line, i think monoblocks will also look pretty nice in my room, haha

In a 10X10 room I just don't see how a 300 W monoblock would give you better sound quality than the Rotel.
In a larger room it would be possible but only because the monoblock has 2.5 dB higher gain their the Rotel so the little Yamaha preamp would not have to be pushed too close to its limit.

In fact, in such a small room, unless you listen at really high level, I would even doubt the Rotel amp is making a different. I do believe you heard a difference, but unless you did it blind, the difference could have been heard under the influence... Sorry about being blunt, just to be honest and base on science. In your system, currently the AVR's preamp vol control will likely be the bottleneck, not the DAC and the power amps.

Yamaha RX-V6A 7.2 channel 4K / 8K Dolby AV Receiver Review | Audio Science Review (ASR) Forum

Regarding the need for blind listening test, in interested you can read section 3 in the linked book by the highly regarded Dr. F. Toole:

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms: Toole, Floyd E.: 9781138921368: Books - Amazon.ca

You said your main goal is better sound quality, then I would suggest focus on the recording quality of the media content (based on your own experience I think you know that already).

And you can in fact make some real gain by going with a better AVR, with or without a better power amp (it depends..), or have a separate two channel preamp + power amp.

 

[Hessel Visser]

In a 10X10 room I just don't see how a 300 W monoblock would give you better sound quality than the Rotel.
In a larger room it would be possible but only because the monoblock has 2.5 dB higher gain their the Rotel so the little Yamaha preamp would not have to be pushed too close to its limit.

In fact, in such a small room, unless you listen at really high level, I would even doubt the Rotel amp is making a different. I do believe you heard a difference, but unless you did it blind, the difference could have been heard under the influence... Sorry about being blunt, just to be honest and base on science. In your system, currently the AVR's preamp vol control will likely be the bottleneck, not the DAC and the power amps.

Yamaha RX-V6A 7.2 channel 4K / 8K Dolby AV Receiver Review | Audio Science Review (ASR) Forum

Regarding the need for blind listening test, in interested you can read section 3 in the linked book by the highly regarded Dr. F. Toole:

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms: Toole, Floyd E.: 9781138921368: Books - Amazon.ca

You said your main goal is better sound quality, then I would suggest focus on the recording quality of the media content (based on your own experience I think you know that already).

And you can in fact make some real gain by going with a better AVR, with or without a better power amp (it depends..), or have a separate two channel preamp + power amp.

Hey Peng! thanks for the reply!
I understand that you are telling me to get rid of the Yamaha, because of it's weak test results..?
I will rewire my set this week and pull the yamaha out of the chain and see how that sound. then my steinberg interface becomes the "preamp", and i will have a all ballanced rig.

And you are telling that i should get the same sound quality with the just the Yamaha amp stage as with the Rotel amp or any amp?

 

[PENG]

Hey Peng! thanks for the reply!
I understand that you are telling me to get rid of the Yamaha, because of it's weak test results..?
I will rewire my set this week and pull the yamaha out of the chain and see how that sound. then my steinberg interface becomes the "preamp", and i will have a all ballanced rig.

And you are telling that i should get the same sound quality with the just the Yamaha amp stage as with the Rotel amp or any amp?

Yes and no, it is complicated and it really depends on things like (just a few examples):

- Your sensitivity to distortions (harmonics, intermodulation, crossover types), noise, and other imperfections such as frequency response, channel balance etc.
- the types of speakers you have.
- the kind of music you listen to.

It seems widely accepted that for distortions to be below most people's threshold of audibility you need distortions to be at the level of no more than 0.1% THD+N, but some people may be bothered by even 0.01% depending on the harmonic profile, while a lot of people wouldn't be able to tell a difference between 0.1% and 1% THD regardless of the harmonic contents. That's base on a few studies that I have read about, and you can also try some of the test I included in the link below:

(2) Amplifier distortions - what, and how much are audible | Audioholics Home Theater Forums

From the measurements, you can see that in your case, the Yamaha's distortions would be between -60 to -80 dB, that's -0.1 to -0.01 % THD+N from about 50 mW to 60 W level, that would likely be within your power requirement for those speakers in that small room.

Also from the measurements, you can see that the Yamaha did quite well in analog, and without any processing engaged. If you use the internal DAC, especially when the signal has to go through the ADC and then DAC, then even the frequency response did not do well at all. Still not that bad for real world use though as a lot of people don't hear that well at above 10 - 15 kHz, let alone 20 kHz.

Yamaha RX-V6A 7.2 channel 4K / 8K Dolby AV Receiver Review | Audio Science Review (ASR) Forum

 

[Hessel Visser]

in this test my speakers and i could notice the difference between pure and 0,005%
But i am not very sure about the reliability because i think the amount of harmonics coming trough seems more that the amount of percents on the labels... But that's just my feeling and not scientific ofcourse...
does that mean that my rig is amplifing the thd?

 

[PENG]

View attachment 46140

in this test my speakers and i could notice the difference between pure and 0,005%
But i am not very sure about the reliability because i think the amount of harmonics coming trough seems more that the amount of percents on the labels... But that's just my feeling and not scientific ofcourse...
does that mean that my rig is amplifing the thd?

I was hoping you would try the Klippel test as well.

Listening Test (klippel.de)

I think such exercise may give us some idea in general sense, that we may not hear as well as we think we can, but the results have to be taken with a bunch of salt as there are too many factors involved.

 

[Hessel Visser]

I was hoping you would try the Klippel test as well.

Listening Test (klippel.de)

I think such exercise may give us some idea in general sense, that we may not hear as well as we think we can, but the results have to be taken with a bunch of salt as there are too many factors involved.

cool test! will check it out tommorrow.

 

[Pogre]

Hey Peng! thanks for the reply!
I understand that you are telling me to get rid of the Yamaha, because of it's weak test results..?
I will rewire my set this week and pull the yamaha out of the chain and see how that sound. then my steinberg interface becomes the "preamp", and i will have a all ballanced rig.

And you are telling that i should get the same sound quality with the just the Yamaha amp stage as with the Rotel amp or any amp?

Basically, if you're looking for improvements in sound quality you're barking up the wrong tree. Once you have sufficient power for your needs and a competently made amp (which most of the big companies today are more than capable), it's down to speaker choice, placement, room acoustics and eq. More power won't make a lick of difference unless you're hitting limits with your current amp and running into distortion at high volumes.

 

[lovinthehd]

Surprised if you're from the pro field audio-wise why you would think the two different amps would be significantly different. I think you're fine with the Rotel, concentrate on more important issues than amplification.

 

[Hessel Visser]

Surprised if you're from the pro field audio-wise why you would think the two different amps would be significantly different. I think you're fine with the Rotel, concentrate on more important issues than amplification.

Maybe because of that background i think different amps is different sound...
I dont care about volume with my amps but i notice sound difference(coloration, dimensional and clarity) in different amps..

 

[Hessel Visser]

Basically, if you're looking for improvements in sound quality you're barking up the wrong tree. Once you have sufficient power for your needs and a competently made amp (which most of the big companies today are more than capable), it's down to speaker choice, placement, room acoustics and eq. More power won't make a lick of difference unless you're hitting limits with your current amp and running into distortion at high volumes.

Thanks! Yeah im just a rookie in hifi, trying to figure everything out..
But now with this amplification story, everybody is telling me te same as you do, so i take your advise..
Thanks

 

[Hessel Visser]

In a 10X10 room I just don't see how a 300 W monoblock would give you better sound quality than the Rotel.
In a larger room it would be possible but only because the monoblock has 2.5 dB higher gain their the Rotel so the little Yamaha preamp would not have to be pushed too close to its limit.

In fact, in such a small room, unless you listen at really high level, I would even doubt the Rotel amp is making a different. I do believe you heard a difference, but unless you did it blind, the difference could have been heard under the influence... Sorry about being blunt, just to be honest and base on science. In your system, currently the AVR's preamp vol control will likely be the bottleneck, not the DAC and the power amps.

Yamaha RX-V6A 7.2 channel 4K / 8K Dolby AV Receiver Review | Audio Science Review (ASR) Forum

Regarding the need for blind listening test, in interested you can read section 3 in the linked book by the highly regarded Dr. F. Toole:

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms: Toole, Floyd E.: 9781138921368: Books - Amazon.ca

You said your main goal is better sound quality, then I would suggest focus on the recording quality of the media content (based on your own experience I think you know that already).

And you can in fact make some real gain by going with a better AVR, with or without a better power amp (it depends..), or have a separate two channel preamp + power amp.

Just removed the Yamaha RXV6A out of my rig, because when i turned up the music louder(louder than i useually do) the Tannoys started to distort like KRAAAAAAzy.
So now its like PC - UR28M - LSR310 sub - RB1552 - Tannoy's
All Ballanced cables, and crossover on the LSR310 set at 80hz
HUGE improvement... No distortion at all! Yeah, well the neighbourhood started to distort

Thanks alot for the advice!

 

[lovinthehd]

Maybe because of that background i think different amps is different sound...
I dont care about volume with my amps but i notice sound difference(coloration, dimensional and clarity) in different amps..

Perhaps between a tubed amp and an ss amp, but you hear such such differences in each amp? Have you double blind tested such belief?

 

[PENG]

Just removed the Yamaha RXV6A out of my rig, because when i turned up the music louder(louder than i useually do) the Tannoys started to distort like KRAAAAAAzy.
So now its like PC - UR28M - LSR310 sub - RB1552 - Tannoy's
All Ballanced cables, and crossover on the LSR310 set at 80hz
HUGE improvement... No distortion at all! Yeah, well the neighbourhood started to distort

Thanks alot for the advice!

If you are using the Yamaha as preamp, don't forget you have to level match the two. At the minimum, when using the internal amps of the RX-V6A, you should turn the volume down by 3 dB lower than when you are using it with the Rotel power amp. That is because the Rotel's gain is about 3 dB lower.

Also, try to compare using just the two Tannoy speakers, in 2 channel stereo in pure direct mode.

 

[Hessel Visser]

Like i wrote yesterday, re-installed everything but then realized i didnt have 5.1 anymore.
So i bought a pair of 2nd hand Tannoy Revolution XT6(the bookshelfs) for 325 euro and now use those as main l/r in the 5.1 set with the RXV6A as 5.1 amplifier/processor.
So from my pc i can just select output and switch between both rigs, going 2.1 to the Steinberg and 5.1 trough HDMI to the RXV6A.
Now the 2.1 rig is also my monitoring set for recording and mixing, but at recordingstage the audio level is waaaay lower as when playing mastered music ofcourse, so i need something to fix that.
I am not sure but a balanced pre amp would fix that right? how much gain can i expect from lets say the Rotel RC 1572?

Output level balanced is 2v..

 

[PENG]

Like i wrote yesterday, re-installed everything but then realized i didnt have 5.1 anymore.
So i bought a pair of 2nd hand Tannoy Revolution XT6(the bookshelfs) for 325 euro and now use those as main l/r in the 5.1 set with the RXV6A as 5.1 amplifier/processor.
So from my pc i can just select output and switch between both rigs, going 2.1 to the Steinberg and 5.1 trough HDMI to the RXV6A.
Now the 2.1 rig is also my monitoring set for recording and mixing, but at recordingstage the audio level is waaaay lower as when playing mastered music ofcourse, so i need something to fix that.
I am not sure but a balanced pre amp would fix that right? how much gain can i expect from lets say the Rotel RC 1572?
View attachment 46184
Output level balanced is 2v..

That's about the same as the Yamaha's:

INPUT SENSITIVITY
Line Level Inputs (RCA): 200mV
Line Level Inputs (XLR): 300mV

You can calculate it as below:
Gain = Output/Input = 1/0.2 = 5, in multiples
or Gain = 20*log10(5) = 13.98 dB

for both units but the Rotel RC1572 will higher 2.5 dB higher gain for XLR.
Keep in mind the Rotel RB1552MkII's gain is 4 dB lower for XLR output, so the overall over gain from preamp input to power amp output would be a little lower if you use balanced inputs.