Lowering noise floor, what has worked for you?

afterburnt

Anything and everything?

ken brydson

Elevator?

afterburnt

ken brydson wrote: »

Elevator?

No silly, the pipe!

afterburnt

I can't wait to find something for my second system, that's where there's the most to be gained.

F1nut

Turning everything off.

afterburnt

F1nut wrote: »

Turning everything off.

Even the stereo?

mhardy6647

F1nut wrote: »

Turning everything off.

... and moving deep into the country.

mhardy6647

As a feller runnin' single-ended, direct heated triode amplifiers (with AC on all the filaments) and 104-ish dB sensitive loudspeakers... one acclimatizes to a wee bit of hum.

afterburnt

@mhardy6647 translation lol

rpf65

Deal with it

txcoastal1

Ear plugs

mlistens03

Not much you can do really. Buy lower distortion gear. Better cables. And the like.
For me it doesn’t bug me because all of my music (and I mean ALL of it) has a lot of harmonic distortion in the background, so the little bit that comes out normally doesn’t bother me.

motorstereo

Dreadnaught

mhardy6647

afterburnt wrote: »

@mhardy6647 translation lol

Actually the issue is really simple. A "triode" has three active elements (electrodes), the plate or anode, the control grid, and the cathode. There is also a filament, which is heated - like the filament of an incandescent light bulb - to serve as a source of electrons.

DSC_0471 (3) by Mark Hardy, on Flickr

A direct-heated triode power output tube has its filament and cathode as the same physical element (thus "direct heated"). The filament is heated with low-voltage AC derived from the power supply. Thus, there's some tendency to have a little AC hum induced into the signal via the tube itself.

How much hum? Typically, maybe a millivolt (i.e., 100 dB below a volt). So, that's not a bad signal to noise ratio -- except when 1 watt of input into one's speakers produces an SPL of 104 dB when measured a meter away!

The combination of a DHT triode power amp and high-sensitivity loudspeakers almost always results in a little residual, audible hum.

That's all.

tonyb

Lowering the noise floor....good topic because everything has potential to raise it within ones system, and even outside it.

Dedicated lines feeding the system can lower the noise floor because you have no other appliances on the circuit, no other lights or gizmos. Quality wall sockets over the crap construction grade ones will also help some.

Power conditioners/regenerators, cables, isolation platforms, spikes, the list is endless. For me, so far....my PS Audio power conditioner did a great job lowering the noise floor. My AZ cables also contributed greatly as well as the Cary dac I use. With every addition of the above, a distinct improvement in noise was heard, noise btw, your unaware is there until it's gone.

....and that's really the crux of the matter with a noise floor, you don't know you have it until it's gone. It becomes part of the music your ears have acclimated themselves to.

mhardy6647

Marky gets his crotchety old audiophile garb on and sez:



The big problem nowadays (besides cr@p on the mains from CFLs and LEDs and power hogs like compressors) is the hash from switching power supplies and RFI crud from high frequency digital processing.

pitdogg2

afterburnt wrote: »

@mhardy6647 translation lol

Hmmmmmmm

mhardy6647

pitdogg2 wrote: »

afterburnt wrote: »

@mhardy6647 translation lol

Hmmmmmmm

well put.

tonyb

Somehow I misplaced my Hardy decoder ring. I'll have to reference the graphs and charts that came in the cereal box.

[Deleted User]

Depending upon the design of your preamp, some reduction in noise can be had by using shorting plugs on unused inputs. Shorting plugs are regular RCA plugs that have had a short piece of wire connecting the center pin to the ground. Some preamps will automatically short unused inputs, but some (preamps that allow a tape recorder to record a second source while listening to another source) don't. This is especially effective with high gain inputs such as phono.
Another way to reduce noise is to tie all of the grounds of your system together and route them to an effective grounding point. The Mitch Cotter company sold a silver plated solid copper grounding bar that had multiple threaded screw holes along its length. It came with some #14 gauge wires that had silver plated lugs attached on both ends. The idea was to ground all of the components in a system to the main bar which in turn was grounded to a single grounding point. Some serious enthusiasts went to the length of constructing an outdoors grounding plane designed along what amateur radio enthusiasts use. I took the easy way and pounded a electrical code grounding bar three feet into the ground and ran a #10 grounding wire.

Joey_V

For me, it was cables and the Torus.

afterburnt

@KennethSwauger I have a house ground with two solid copper spikes at least three feet if not five feet into the ground strung together with what has to be at least 00 copper cable. Where would one look for ground caps for unused RCA's?

[Deleted User]

Usually they either are supplied by the component manufacturer or built by hand. It's really very simple and is a good place to begin soldering as a path to enlightenment.

afterburnt

Thanks Ken. Oxyacetylene is the only path to enlightenment.

[Deleted User]

I'd be happy to make a couple of pairs for you, gratis. PM me if interested.

afterburnt

@KennethSwauger Most magnanimous of you! Where would said devices be best applied?

afterburnt

PM sent

[Deleted User]

I would recommend the phono inputs since that involves the most amount of signal gain. This is assuming you're not using it. Really any input that doesn't have a component connected to it.

afterburnt

I will try them on my vacant preamp inputs, you are El Chingon!

steveinaz

- Quality cables
- Cable management, esp digital sources/cables

jeremymarcinko

Getting the kids to bed.

For the phono section of my Yamaha integrated I have found I can drastically reduce the noise floor by pulling the usb cable from the laptop that connects it to the Yamaha.