Regarding @spinaker01's comment: "The power infrastructure is a good idea but effect varies depending on the quality of the house wiring (and external) components. I generally find newer neighbourhoods under 10 years old to be pretty good."
I agree that newer homes are probably better off than older homes with respect to power. With time, circuit breakers, connectors, outlets, or anything else in the circuit with exposed copper will oxidize resulting in higher resistance. But new homes, even within the last 10 years, very seldomly provide an adequate power infrastructure for audio, even with modest systems.
One of the most cost-effective upgrades I have experienced and can, therefore, recommend, is a dedicated line but not for the reason that most expect -- noise isolation -- but rather to lower line resistance. And I have found this to be effective not just for power hungry amplifiers but for EVERY component in my chain. Based on how you spelled "neighbourhoods." I presume you are not based in the U.S. but by U.S. electrical code definitions, a 20 amp dedicated line will have 12 gauge wire in the wall and so while some will claim they have a "dedicated line," according to Vince Galbo of MSB, "12 gauge wire is absolutely insufficient for high end audio systems" and that "the gauge of the wire is FAR MORE IMPORTANT than the fact that the line is dedicated." For those interested in more of what Vince has to say, here is that link:
http://www.msbtechnology.com/faq/how-to-wire-your-house-for-good-power/
My present home is 10 years old and utilizes 14g wire in the wall along with inexpensive Leviton outlets. Some time ago, in one of my listening rooms, I had 20A dedicated lines installed with 10 gauge Romex for about $300 per line including labor and was very impressed with the improvement. More recently, I had more dedicated lines installed in this same room but also in my large listening room that houses my Wilsons but this time, I used 6 gauge wire in the walls. This wiring is not the exorbitantly priced in-wall wiring that you can buy from JPS Labs or Audience or WyWires but was better than standard 6 gauge Romex and it cost me about $10 per foot or roughly $800 per line which is still much less than many power cords you can buy. In one location in my house, I have a 6 gauge line within a foot of one of my older 10 gauge lines which is within a foot of a 14 gauge line that came with the house and so it became very easy to do an A/B/C comparison and so with my audiophile group, we did blind testing. As I plugged my components into the 14 gauge vs 10 gauge vs 6 gauge line, it was impressive how dynamic contrasts improved but also by how the presentation became more relaxed, open and effortless and this was easily detectable under blind testing. This is probably the most cost-effective upgrade I can think of.
As for outlets, they do make a difference. The cheap Leviton Decora outlets that came with my house use fairly small gauge brass connectors that are conductive enough to power a lamp or a toaster but leave much to be desired when powering an amp or a DAC. If you are going to install large gauge wiring in your walls, it would make no sense to keep the cheap outlets that came with your home. I have found certain Hubbell outlets to be much more conductive simply because they use larger gauge conductors (I paid $50 each for these). I am also very impressed with the Furutech GTX-D(R) NCF outlets which use much more conductive pure copper (i.e. no brass) which is then plated with Rhodium although these Furutechs are a touch brighter than the Hubbells that I have. Also, the Hubbells that I have can accommodate 6 gauge wiring without having to resort to pigtails whereas the Furutechs can only accommodate a maximum of 8 gauge wiring.
When designing a dedicated room for either 2-channel or home theater, power infrastructure needs to be very intentional and it is much easier to implement it while the room is being built than after the fact.
As for line conditioning and power cords, that is another conversation altogether and while these are important considerations for all gear, even if you have dedicated lines, rather than take this thread too far off topic, here is my journey with line conditioners for those who are interested:
https://forums.stevehoffman.tv/threads/i-use-amazing-sound-application-linestage-power-conditioners-...
For those who are skeptical about the impact of power cables, over the years, I have probably spent more time comparing power cables than any other component and even when subjected to blind testing, in the most extreme instances, I have found a power cord to make a greater difference than an amplifier upgrade. Here is a helpful link:
https://www.gcaudio.com/tips-tricks/why-power-cables-make-a-difference/
I agree that newer homes are probably better off than older homes with respect to power. With time, circuit breakers, connectors, outlets, or anything else in the circuit with exposed copper will oxidize resulting in higher resistance. But new homes, even within the last 10 years, very seldomly provide an adequate power infrastructure for audio, even with modest systems.
One of the most cost-effective upgrades I have experienced and can, therefore, recommend, is a dedicated line but not for the reason that most expect -- noise isolation -- but rather to lower line resistance. And I have found this to be effective not just for power hungry amplifiers but for EVERY component in my chain. Based on how you spelled "neighbourhoods." I presume you are not based in the U.S. but by U.S. electrical code definitions, a 20 amp dedicated line will have 12 gauge wire in the wall and so while some will claim they have a "dedicated line," according to Vince Galbo of MSB, "12 gauge wire is absolutely insufficient for high end audio systems" and that "the gauge of the wire is FAR MORE IMPORTANT than the fact that the line is dedicated." For those interested in more of what Vince has to say, here is that link:
http://www.msbtechnology.com/faq/how-to-wire-your-house-for-good-power/
My present home is 10 years old and utilizes 14g wire in the wall along with inexpensive Leviton outlets. Some time ago, in one of my listening rooms, I had 20A dedicated lines installed with 10 gauge Romex for about $300 per line including labor and was very impressed with the improvement. More recently, I had more dedicated lines installed in this same room but also in my large listening room that houses my Wilsons but this time, I used 6 gauge wire in the walls. This wiring is not the exorbitantly priced in-wall wiring that you can buy from JPS Labs or Audience or WyWires but was better than standard 6 gauge Romex and it cost me about $10 per foot or roughly $800 per line which is still much less than many power cords you can buy. In one location in my house, I have a 6 gauge line within a foot of one of my older 10 gauge lines which is within a foot of a 14 gauge line that came with the house and so it became very easy to do an A/B/C comparison and so with my audiophile group, we did blind testing. As I plugged my components into the 14 gauge vs 10 gauge vs 6 gauge line, it was impressive how dynamic contrasts improved but also by how the presentation became more relaxed, open and effortless and this was easily detectable under blind testing. This is probably the most cost-effective upgrade I can think of.
As for outlets, they do make a difference. The cheap Leviton Decora outlets that came with my house use fairly small gauge brass connectors that are conductive enough to power a lamp or a toaster but leave much to be desired when powering an amp or a DAC. If you are going to install large gauge wiring in your walls, it would make no sense to keep the cheap outlets that came with your home. I have found certain Hubbell outlets to be much more conductive simply because they use larger gauge conductors (I paid $50 each for these). I am also very impressed with the Furutech GTX-D(R) NCF outlets which use much more conductive pure copper (i.e. no brass) which is then plated with Rhodium although these Furutechs are a touch brighter than the Hubbells that I have. Also, the Hubbells that I have can accommodate 6 gauge wiring without having to resort to pigtails whereas the Furutechs can only accommodate a maximum of 8 gauge wiring.
When designing a dedicated room for either 2-channel or home theater, power infrastructure needs to be very intentional and it is much easier to implement it while the room is being built than after the fact.
As for line conditioning and power cords, that is another conversation altogether and while these are important considerations for all gear, even if you have dedicated lines, rather than take this thread too far off topic, here is my journey with line conditioners for those who are interested:
https://forums.stevehoffman.tv/threads/i-use-amazing-sound-application-linestage-power-conditioners-...
For those who are skeptical about the impact of power cables, over the years, I have probably spent more time comparing power cables than any other component and even when subjected to blind testing, in the most extreme instances, I have found a power cord to make a greater difference than an amplifier upgrade. Here is a helpful link:
https://www.gcaudio.com/tips-tricks/why-power-cables-make-a-difference/