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Hum, buzz, and hiss

Run your levels high, at 0 dB rather than, say, -30dB. To high, and you get clipping; too low, and the hiss is louder relative to the signal. If each processor module had a clipping light, and a level control, you could keep the level just below clipping at every stage, so your chain would be as quiet as possible without clipping.

Any effects before any saturation/distortion stage need to have as little self-noise as possible. Which is to say, a lot of headroom. Headroom is the difference between a processor's level of self-noise and the level at which the processor clips the signal. For eq before distortion (for controlling the distortion voicing somewhat), use a rackmount EQ with a high signal/noise rating.

How to Solve Hum and Buzz Problems - in PAs, racks, and guitar rigs. $11.95. The address is/was: Bross Electronics, 350 Tremont Dr., Ste. D-51, Dept. G11, Murfreesboro, TN 37130. Nov 1988 Guitar Player magazine ad, page 159. Try an AltaVista search for the company name or document title.

> c_crawl at hotmail.com wrote: ----- My guitar pedals produce a lot of noise/hiss and this is annoying when trying to record. Between the lights in the room and the noisy wall socket power source, it can get really bad. Are there any products to clean up my setup? -----

Rick Suter wrote:

Strictly speaking there's a difference between noise and interference. Many lump them together and just call it all noise as they're both obnoxious.

Noise is the thermal and shot noise from resistors and active devices due to random electron motion. It generally sounds like hiss. It is usually due to poor circuit design, a bad component, or really excessive gain. (change or eliminate pedals, get quieter preamp tubes, reduce gain, etc.)

Interference can be a hum/buzz from power lines, transformers, fluorescent lights, TV's, any digital device, computer monitors, radio/TV stations, etc. With any interference problem there are 3 things you can go after.

1) the source - quiet it, move or reorient it, turn it off, slow the edge rates (digital interference) balance it, kill it... if possible.

2) the transmission path - electromagnetic (capacitive or magnetic) coupling or a conducted path (wire) - attenuate the path by shielding or filtering

3) the receiver - the device in the signal chain that picks up the interference, including wires/cables that act as an antenna. - not much we can do outside of making sure the layout in the sensitive area is short and clean. You can bandwidth limit (filter) the signal path for RF interference but if the interference is in the middle of the audio band you pretty much stuck.

See the other postings in the thread How to reduce pedal hiss/noise.

Hum from ungrounded bridge

I ran into this same problem twice in one week -- first, when using a used humbucker in a Stratocaster to test an effect, and then, when testing my guitar that I had custom-loaded with guts.

Both guitars did not decrease in hum level when I touched the strings or bridge. I knew instantly that the strings were not grounded. A professional technician at Torres Guitars, with years of experience, forgot to do this, and it was amusing and reassuring of my experience that I was able to spot the problem in seconds. He had not tested the guitar using distortion. But distortion brings out a lot of problems in guitars, such as wobbly string tone, vibrations, and noise problems. More than one guitar tech has told me I'm just imagining noise problems in a guitar. But they plug into a clean amp, and say "see, I don't hear any noise problem". Of course they can't hear the problem, using only a clean amp -- distortion acts as a microscope or amplifier for some types of noise.

Active pickups to reduce hum

Mark Anthony wrote:

>Here is a solution for Hum...use EMG active pickups! They have no noise, and more output. I use them in every guitar that I own.

>Mark (kanth at pcms.com)

Thanks for the pointer to EMG active pickups. I might try this. These days, "acoustic" guitars have more electronics (eq) than "electric" guitars, and we gearheads have to catch up.

Adder Plus Corp. - Humphree Pickups. Single-coil. $95. models 100, 200, 300, and 400.

Fender Pro Jr. tube amp is noisy

jstrater at wv.mentorg.com (Jeff Strater) wrote:

>Hi all,

>I have a Fender Pro Jr amp, which I like for the most part, but it
>is VERY noisy. I get lots of static, and the occasional radio station
>coming through. It happens even with no instrument plugged in. It
>can vary depending on how the amp is turned, or if a guitar is
>plugged in, how the cord is arranged.

>Can this be a tube problem? If so, which tubes should I try replacing
>the preamp, or the amp tubes? Or, is this basically a shielding problem,
>and if so, can I fix it? I'm not an electronics expert at all, so
>are there any references that can give me explicit instructions on how to
>shield an amp? Or should I have a pro do it, in which case, how much should
>I expect to pay for such a service?

>Thanks for your help,

>Jeff (jeff_strater at mentorg.com)

I had one. It's true, I read it in a review too. The Pro Jr. is a noisy amp. Also, it doesn't have much headroom for load clean playing either. I think it's overrated. Perhaps the Soldano 16 watt all-tube amp is better. Because of the hiss, the lack of tonal control, the exagerrated mid-bass, and the lack of clean headroom, this amp should be re-designed. I do not recommend buying the Pro Jr if you want a 15-watt amp.

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