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Lowering the noise floor

I am coming to the conclusion that success in home audio reproduction is largely about lowering the noise floor. There are so many different types of “noise”, from so many different sources, that we only really “hear” by their absence.

Those components, cables, accessories and tweaks that SUCCEED at lowering the noise floor, can, and do, dramatically increase sound quality. Sometimes the type of “noise” dealt with is controversial, or not (yet) widely recognized as being a problem. Sometimes the explanation of how a product works is dubious. Sometimes the way it is marketed reeks of “snake oil”. Sometimes the reviews singing its praises go over the top. While these things will certainly put off some prospective purchasers, they do not negate the audible results that are there for anyone open to hearing them.
tommylion
georgehifi's avatar
georgehifi
10,312 posts
 
gdhal Wouldn’t that be a moot point if one is using an integrated amp?

The OP tommylion uses a 2A3 poweramp with an input impedance of 100kohm and very high gain at just 500mV input for full wattage output.
There is 2000mV (2v) or more available from any source these days, why add another gain stage with an active pre???.
This is a perfect scenario for a passive preamp.

Any active preamp no matter how expensive, is a backward step, not just in noise but also sound.
http://www.divertech.com/asltulip.html

Cheers George

hifiman5's avatar
hifiman5
1,832 posts
 
My system actually exhibits a lower noise floor now after adding tubes to the system.  Originally I had only two 12AU7s in my line stage and all was well. After having my SACD player modified by Dan Wright and company, which added two 5687s and a 5AR4 rectifier to the mix things are actually quieter when the digital source is selected than before.  I feel secure in giving some of the credit to my PS Audio P5 power regenerator.  2.0% distortion in, .1% out!
tommylion OP
874 posts
 
Proper grounding is another way to lower the noise floor. I just got a GutWire Ultimate Grounding Cable, and hooked it up to my pre. I noticed an immediate difference.

https://forum.audiogon.com/discussions/gutwire-ultimate-grounding-cable


georgehifi's avatar
georgehifi
10,312 posts
 
Proper grounding is another way to lower the noise floor.
That’s a given for LF hum, but for HF noise it’s a bit more complex.

Cheers George
geoffkait's avatar
geoffkait
23,365 posts
 
Here some (uncontroversial) sources of noise or distortion that might not have been mentioned.

1. The induced magnetic field produced by the large transformer that extends outward to all electrical components and wiring in proximity.

2. The mechancal noise produced by the large transformer and direct coupled to the chassis and the circuit boards.

3. Low frequency seismic vibration that is capable of exciting the resonant frequencies of the turntable platter, tone arm and cartridge AND of affecting the laser reading process in CD players, producing jitter.
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