External Amps dont make a difference ...whaa?

[AdrianQ]

Hi everyone ,very confused person here.

After reading a previous thread "AV Receivers and external amp. " I seemed to get the consensus from the forum that external power amps dont improve sound quality. I'm not disagreeing ..because I dont have the experience to do so but I just dont understand this.
The parts in an av receivers amp section cant be as good as a dedicated external amp. People are always singing high praises with amps from Mcintosh, Rotel etc etc. People are always talking about better soundstage ,dynamics and being able to hear more nuances from their speakers with external amps.
I have a Marantz SR-6012 , I definitely prefer its sound quality over my older Yamaha (not an expensive model ). I recently purchased a Crown XlS-1502 to use for the Front L & R via SR-6012 pre-out .. I absolutely dont like the sound of the Crown . (I wanted to like it ..I really tried) .
To be fair to Crown owners and future one's , I dont like its sound signature and its also producing a feedback through all my six speakers even when it has no speakers attached to it and with the power chord out . Once I attach the pre-out cable feeback begins . This could be purely My system problem and not the Crowns .( I will ask about this in a different Thread).
I was going to buy the Marantz MM 7025 as an upgrade and also to start a system with dedicated separates but now I'm totally confused. I wasnt much concerned with Raw Power as much as an External Amps reproduction capabilities being better than an AVERAGE avr.
Please help me understand this ,thanks Adrian

 

[lovinthehd]

Sounds like a ground loop hum for the noise issue. I have Crowns and other amps and sound quality doesn't magically happen when you hook them up to an avr in my experience, altho the better impedance capabilities or power may have benefits. Depends on the speakers and your listening levels. An amp simply amplifies a signal, it shouldn't have a signature....never found my Crowns (XLS1500) to have a "signature" when attached to any of my avrs (a couple Denons and an Onkyo). You do get a lot of folks getting excited about their high power amps. I am not an ampli-phile, tho. They're simply tools within a system....and I wouldn't want one with a "signature" particularly...

 

[AdrianQ]

Sounds like a ground loop hum for the noise issue. I have Crowns and other amps and sound quality doesn't magically happen when you hook them up to an avr in my experience, altho the better impedance capabilities or power may have benefits. Depends on the speakers and your listening levels. An amp simply amplifies a signal, it shouldn't have a signature....never found my Crowns (XLS1500) to have a "signature" when attached to any of my avrs (a couple Denons and an Onkyo). You do get a lot of folks getting excited about their high power amps. I am not an ampli-phile, tho. They're simply tools within a system....and I wouldn't want one with a "signature" particularly...

I read so much on ground loops and obviously still dont understand it fully but how do I get a ground loop if the crown isn't even plugged in to anything, only the two rca's from my avr ? I've also grounded both chassis together but still can hear a high pitch feedback.

 

[lovinthehd]

I read so much on ground loops and obviously still dont understand it fully but how do I get a ground loop if the crown isn't even plugged in to anything, only the two rca's from my avr ? I've also grounded both chassis together but still can hear a high pitch feedback.

What speakers are you using? Might be best if you explained the entire system and connections to understand better. You get a high pitched whine from the speakers that are still powered by your avr just by having rca's connected to the Crown when the Crowns are not plugged into power?

 

[PENG]

I was going to buy the Marantz MM 7025 as an upgrade and also to start a system with dedicated separates but now I'm totally confused. I wasnt much concerned with Raw Power as much as an External Amps reproduction capabilities being better than an AVERAGE avr.
Please help me understand this ,thanks Adrian

Parts with better specs does not always translate into audible differences. For example, if your SR6012 would truly measure less than 0.08 % THD+N, and if most accept 0.1% THD+N being not audible no matter what the harmonic contents are, then an external amp that has THD+N specified or 0.05% THD+N, such as the MM7025 is not going to make your speakers sound better to you right? Also consider the much higher distortions you speakers offer, so logically speaking you can't expect them to be able to resolve the minute difference in distortions between two amps.

What else can we say to convince you? Keep in mind many of those (including me) who told you adding an external amp don't always improve SQ for those who asked, do own external amps. I own several external amps including a MM8003 that is similar to the 7025 but has 8 channels and obviously has a much larger power supply. I can tell you while it is a good feeling to have them, none offer any obvious difference in sound quality, all else being equal. People will say all those things you read on forums and magazine reviews, but that's expected because if something cost a lot more, better looking, better build quality, they have to sound better..

ASR just published a review with measurements on the $2,200 Marantz AV7705. It measured pretty much as good but not better than the $999 Denon AVR-X3500H, yet on forums people would rave about their Marantz sound, or vice versa. Same deal, you have to either believe those talks or learn to filter them accordingly.

 

[Mikado463]

I'm confused as well, your speakers aren't connected yet you're getting feedback through them ?

 

[lovinthehd]

I'm confused as well, your speakers are connected yet you're getting feedback through them ?

? That's confusing

 

[Mikado463]

? That's confusing

opps, my bad, corrected...

 

[Gmoney]

I'm confused as well, your speakers aren't connected yet you're getting feedback through them ?

I know I read that to, OP says, even when no speakers connected and power cord is out. What’s missing here?

 

[AdrianQ]

I'm confused as well, your speakers aren't connected yet you're getting feedback through them ?

Sorry I didnt explain that properly . My speakers are all connected to my Marantz SR-6012 . In this configuration there is no hum or feedback. If i connect my Marantz pre-outs to the Crown I will get a high pitch feedback from all my speakers ,it is not loud but it is their. Bare in mind that the Crown is not plugged in and has no speakers attached to it. I also tried chassis grounding both units together ,this made no difference I also bought a voltage regulator and line filter and this made no difference either.
Any Ideas?

 

[AdrianQ]

Sounds like a ground loop hum for the noise issue. I have Crowns and other amps and sound quality doesn't magically happen when you hook them up to an avr in my experience, altho the better impedance capabilities or power may have benefits. Depends on the speakers and your listening levels. An amp simply amplifies a signal, it shouldn't have a signature....never found my Crowns (XLS1500) to have a "signature" when attached to any of my avrs (a couple Denons and an Onkyo). You do get a lot of folks getting excited about their high power amps. I am not an ampli-phile, tho. They're simply tools within a system....and I wouldn't want one with a "signature" particularly...

I do believe I can hear a difference between the Marantz and the Crown. Obviously I want to like the Crown or I wouldnt have bought it. Can you tell me if ground loops or feedbacks can effect the sound quality on a whole? Even though the feedback is of a low volume can it subtly mess with the entire signal ?

 

[AdrianQ]

What speakers are you using? Might be best if you explained the entire system and connections to understand better. You get a high pitched whine from the speakers that are still powered by your avr just by having rca's connected to the Crown when the Crowns are not plugged into power?

My system is a PC connected via Toslink to my AVR which is connected to Klipsch Rp-8000f (front channel) , Paradigm Monitor 11 v6 ( surround) , Klipsch Rf82ii (surround back). All equipment connected to a voltage regulator and noise filter (which made no difference)
As to your question "You get a high pitched whine from the speakers that are still powered by your avr just by having rca's connected to the Crown when the Crowns are not plugged into power?" YEP the moment the rca's are connected to the Crown all speakers connected to the AVR emit a low volume high pitch noise.

 

[KEW]

People will say all those things you read on forums and magazine reviews, but that's expected because if something cost a lot more, better looking, better build quality, they have to sound better..

I'd like to frame this a little differently for Adrian to perhaps understand it better.
We do have an expectation bias that a more expensive unit dedicated to a specific task would perform better, but as Peng says, it may perform better, but the difference is not likely to be audible!
But as far as the perception that it sounds better, don't look at it as simply the cost so much as that you have been anticipating that new amp. You have invested research in picking it and sacrificed time to earn the money to buy it.
I think food is a reasonable analogy as if you spent the last 2 hours preparing special food (or even sitting in the kitchen watching it being prepared), the anticipation is going to result in heightened attention to the taste of the food and you will enjoy it more than you would if you just walked in the door (not thinking about food)!
Similarly, if we spent the last 1/2 hour driving home thinking about listening to a favorite song on our system, that song will generally sound more profoundly great than it would if it just popped up on a shuffle play.
You can look at it as being more alert to the sound and thus taking in a little more nuance than you otherwise might, or you can think of it as biochemical endorphins/stimulants that your body generates from your anticipation!
In the end, we humans are ill-suited to doing fine comparisons of our sensory inputs. If you consider color, we use paint chips to ID the color we want with a bit of precision, because we know we cannot remember the exact specifics of a color to the level of precision that the paint chips offer. Sound is maybe even less so and there is no "paint chip" for sound!
Yeah, you can hear the difference between very good and poor speakers, but the difference between speakers is humongous when compared to the difference between modern competently designed amps (unless you are overloading one of the amps so it is not performing as designed)!

On the Crown, I would postpone judgement until you have the source of the noise resolved. It certainly has the potential to impact the sound!
Even so you simply cannot trust your ears unless you have removed knowledge of what you are listening to. That is why rigorous research requires double-blind testing!
Just as a fun demonstration of how our eyes can override what our ears hear, here is a 2 minute clip on the McGurk effect:

 

[AdrianQ]

Parts with better specs does not always translate into audible differences. For example, if your SR6012 would truly measure less than 0.08 % THD+N, and if most accept 0.1% THD+N being not audible no matter what the harmonic contents are, then an external amp that has THD+N specified or 0.05% THD+N, such as the MM7025 is not going to make your speakers sound better to you right? Also consider the much higher distortions you speakers offer, so logically speaking you can't expect them to be able to resolve the minute difference in distortions between two amps.

What else can we say to convince you? Keep in mind many of those (including me) who told you adding an external amp don't always improve SQ for those who asked, do own external amps. I own several external amps including a MM8003 that is similar to the 7025 but has 8 channels and obviously has a much larger power supply. I can tell you while it is a good feeling to have them, none offer any obvious difference in sound quality, all else being equal. People will say all those things you read on forums and magazine reviews, but that's expected because if something cost a lot more, better looking, better build quality, they have to sound better..

ASR just published a review with measurements on the $2,200 Marantz AV7705. It measured pretty much as good but not better than the $999 Denon AVR-X3500H, yet on forums people would rave about their Marantz sound, or vice versa. Same deal, you have to either believe those talks or learn to filter them accordingly.

Not arguing just asking but in your collection of amps is there not one you favor over the other because of some sound quality difference? I just thought that different Toplogies of amps and better parts in general would make a difference.

 

[AdrianQ]

I'd like to frame this a little differently for Adrian to perhaps understand it better.
We do have an expectation bias that a more expensive unit dedicated to a specific task would perform better, but as Peng says, it may perform better, but the difference is not likely to be audible!
But as far as the perception that it sounds better, don't look at it as simply the cost so much as that you have been anticipating that new amp. You have invested research in picking it and sacrificed time to earn the money to buy it.
I think food is a reasonable analogy as if you spent the last 2 hours preparing special food (or even sitting in the kitchen watching it being prepared), the anticipation is going to result in heightened attention to the taste of the food and you will enjoy it more than you would if you just walked in the door (not thinking about food)!
Similarly, if we spent the last 1/2 hour driving home thinking about listening to a favorite song on our system, that song will generally sound more profoundly great than it would if it just popped up on a shuffle play.
You can look at it as being more alert to the sound and thus taking in a little more nuance than you otherwise might, or you can think of it as biochemical endorphins/stimulants that your body generates from your anticipation!
In the end, we humans are ill-suited to doing fine comparisons of our sensory inputs. If you consider color, we use paint chips to ID the color we want with a bit of precision, because we know we cannot remember the exact specifics of a color to the level of precision that the paint chips offer. Sound is maybe even less so and there is no "paint chip" for sound!
Yeah, you can hear the difference between very good and poor speakers, but the difference between speakers is humongous when compared to the difference between modern competently designed amps (unless you are overloading one of the amps so it is not performing as designed)!

On the Crown, I would postpone judgement until you have the source of the noise resolved. It certainly has the potential to impact the sound!
Even so you simply cannot trust your ears unless you have removed knowledge of what you are listening to. That is why rigorous research requires double-blind testing!
Just as a fun demonstration of how our eyes can override what our ears hear, here is a 2 minute clip on the McGurk effect:

Thank you for the analogies ,I do get what you mean, Kinda.
I know that some of the members on this Forum have invested thousands in to their system all in the pursuit of betterment and I have to assume that bit by bit over time they've found it. I expect their systems to sound better because of their investment and audio knowledge. So when somebody says "meh, a power amp is a power amp" it goes against everything that I thought I knew. Maybe the articles , marketing and adverts have trained me well

 

[lovinthehd]

Have you tried lifting the ground on the Crowns with a cheater plug just to see if that's the issue?

As to using power amps on avrs, I've done so for many years up until recently. I'm deliberately keeping the volume down as tinnitus has started to say hello and I'm just being nicer to my ears....my avrs have sufficient power (and quality of amp) to not require the power amps. I use my Crowns (4 XLS1500s) as sub amps and in one 2-ch setup. I have other power amps as well. Back when I first switched from a 2ch receiver (a Marantz 2270 long ago) to a 2ch setup with separate preamp/power amp, I was also a bit disappointed in that the hype said there should be a huge difference....there wasn't. As far as sq changes, perhaps a bit clearer at higher volume. I've tested that with the various amps on a few different avrs (I do prefer to buy an avr with pre-outs) and different speaker setups in different rooms and hasn't changed my mind.

 

[KEW]

Thank you for the analogies ,I do get what you mean, Kinda.
I know that some of the members on this Forum have invested thousands in to their system all in the pursuit of betterment and I have to assume that bit by bit over time they've found it. I expect their systems to sound better because of their investment and audio knowledge. So when somebody says "meh, a power amp is a power amp" it goes against everything that I thought I knew. Maybe the articles , marketing and adverts have trained me well

Well, you have to figure that the magazine reviews are written by people who largely earn their living from the money paid by advertisers. Don't bite the hand that feeds. But advertisers would not stay if you wrote "Yawn, another amp - does what it should."
I have not, and never plan to get into high-dollar amps, thanks to Peng and some others, who did get into high dollar amps and came to the eventual conclusion that they offered no audible benefit. After all, we have had very capable amps since the 70's so it is a very mature science. Manufactures claim new technology (like Marantz with their HDAM circuits) but we don't see any clear improvement in the measurements.
All that said, I would love me some big blue McIntosh mono-blocks with meters, just cause, but not happening this life - I've got more important stuff to spend money on, and even if I won the lottery, I'd rather donate it to charity (unless it was a real big lottery, than I might toss some money at amps). For now, I'm content with my recently reacquired Aragon 2007:

Aragon - 2007 (Klipsch)

www.aragonav.com

However, honestly, the amp sections of my AVRs do fine with my current speakers. My best justification for external amps is to remove some of the heat from the AVR (especially with the current Denon and Marantz which can be run in ECO mode which drops the AVR temp by about 10 degrees F)!

 

[AdrianQ]

Have you tried lifting the ground on the Crowns with a cheater plug just to see if that's the issue?

As to using power amps on avrs, I've done so for many years up until recently. I'm deliberately keeping the volume down as tinnitus has started to say hello and I'm just being nicer to my ears....my avrs have sufficient power (and quality of amp) to not require the power amps. I use my Crowns (4 XLS1500s) as sub amps and in one 2-ch setup. I have other power amps as well. Back when I first switched from a 2ch receiver (a Marantz 2270 long ago) to a 2ch setup with separate preamp/power amp, I was also a bit disappointed in that the hype said there should be a huge difference....there wasn't. As far as sq changes, perhaps a bit clearer at higher volume. I've tested that with the various amps on a few different avrs (I do prefer to buy an avr with pre-outs) and different speaker setups in different rooms and hasn't changed my mind.

The purpose of these forums for me is to learn and swap opinions. You and others do share the same opinion on my External Amp question and I will use this to further my audio quest in other directions other than amps . Maybe put in towards new speakers or some room treatments.

As for my Crown issue it will produce the feedback with no power cord plugged in and a ground between AVR and the Crown Chassis. I have 3ft shielded rca's and the moment I plug them in to the crown I can hear the feedback . My speakers are not connected to the crown they are connected to my AVR but the crown will still produce feedback in all six speakers once its connected to my AVR via the pre-outs.

Out of curiosity when using your crowns as sub amps how do you get phase control? Is their a product they sell to do this?

 

[KEW]

Out of curiosity when using your crowns as sub amps how do you get phase control? Is their a product they sell to do this?

Once you have the Crown properly integrated into your system (and working properly), you would run the setup program built into your AVR to match the phase of the subs.

 

[AdrianQ]

Well, you have to figure that the magazine reviews are written by people who largely earn their living from the money paid by advertisers. Don't bite the hand that feeds. But advertisers would not stay if you wrote "Yawn, another amp - does what it should."
I have not, and never plan to get into high-dollar amps, thanks to Peng and some others, who did get into high dollar amps and came to the eventual conclusion that they offered no audible benefit. After all, we have had very capable amps since the 70's so it is a very mature science. Manufactures claim new technology (like Marantz with their HDAM circuits) but we don't see any clear improvement in the measurements.
All that said, I would love me some big blue McIntosh mono-blocks with meters, just cause, but not happening this life - I've got more important stuff to spend money on, and even if I won the lottery, I'd rather donate it to charity (unless it was a real big lottery, than I might toss some money at amps). For now, I'm content with my recently reacquired Aragon 2007:

Aragon - 2007 (Klipsch)

www.aragonav.com

However, honestly, the amp sections of my AVRs do fine with my current speakers. My best justification for external amps is to remove some of the heat from the AVR (especially with the current Denon and Marantz which can be run in ECO mode which drops the AVR temp by about 10 degrees F)!

I was just getting comfortable with believing what you said.... Until I saw the picture of that Aragon ! It looks awesome