Electric violin amp issues

[Gregg]

Hi,

I have a friend who plays electric violin and recently he complained to me about "bow noise". Honestly I haven't heard anything about this over the years but that's maybe because I didn't know violin players. So he demonstrated to me what he was talking about and I can tell that this sounded like the same "tik tik" when you hit a string with a pick. However he assured me that this noise is very annoying and not only to him. He tried several different tube amps and noticed that when plugging into a drive channel (at low gain settings) this noise is gone. I assumed because the drive channel usually has a compressed sound and he confirmed that a compressor handles that problem very well but also affects the overall sound. That left me thinking how to have a clean amp that doesn't have "bow noise".
I would be glad to hear your comments on that.

[MarkusBass]

Usually, drive channels have much lower gain in low frequency range. So my first suggestion is to turn the BASS pot counterclockwise. If it helps, decrease the gain for low frequencies. What amp is it?

Mark

[g1]

This sounds to me like perhaps putting an electronic band-aid on an acoustic problem?
Bow noise is not limited to electric players. Bow hair & age, strings, and rosin all contribute to the problem or solution.
It's a huge can of worms to open, and to top it off there are bows alone that are worth more than many of us will earn in the rest of our lifetimes.

[Leo_Gnardo]

he demonstrated to me what he was talking about and I can tell that this sounded like the same "tik tik" when you hit a string with a pick. However he assured me that this noise is very annoying and not only to him. He tried several different tube amps and noticed that when plugging into a drive channel (at low gain settings) this noise is gone. I assumed because the drive channel usually has a compressed sound and he confirmed that a compressor handles that problem very well but also affects the overall sound. That left me thinking how to have a clean amp that doesn't have "bow noise".

Interesting observation & test. There are all sorts of compressors and all sorts of ways of applying them. What your friend may want to consider is a "peak limiter" to minimize the tik tik of bow attack and leave the rest of the signal alone dynamically. It's always a compromise, when you change something, pass a complex signal thru a circuit, you're bound to hear something - more so with some classically trained musicians who seem to have eagle ears.

Which limiter to get? Sorry I don't have an answer as I'm not up on the latest offerings. In the meantime it may pay to record some violin passages and try whatever digital 'plug-in' limiters you can find to demonstrate the method & see whether it might be acceptable. You'll need to dial in short attack & decay times to avoid making the compression obvious. Testing this way will be a lot cheaper than buying a pile of gear.

[Enzo]

Yeah a lot of noises are not electronic. I have a problem with guitar string noise. When I move my hand up and down the neck, I get noise like walking in tight new corduroy pants. VWWWOOOPP. I asked someone how to get rid of that, and they said "practice". Big help, after 40 some years, I think II have practiced, but what specifically? ALl of which is to say maybe for amplification and little tweaking of technique?

[Gregg]

Usually, drive channels have much lower gain in low frequency range. So my first suggestion is to turn the BASS pot counterclockwise. If it helps, decrease the gain for low frequencies.

It's just a power amp, no EQ only Volume between the first triode and the PI (cathodyne).
I tried decreasing the cap value going to the Volume pot but it didn't help.
It looks like using a limiter is a good idea. The most simple one I can think of (and least "invasive") is from Ampeg SVT4Pro preamp. However since the amp has 0 db input sensitivity using a voltage divider as per Ampeg schematic will make it less sensitive.
After some more thinking that thing must be very fast in order to take the peaks down and those Vactrols are not that fast.

[J M Fahey]

I have made lots of amplifiers specifically for violin, cello and double bass.
Never ever had a complaint about bow noise.
Not meaning it does not exist, but that it's part of the sound. Think the famous "Hammond dirty keyboard click noise" which had to be added to electronic keyboards emulating them.
IF your friend has more than usual, making it annoying or even unbearable, then he must attack the problem at the root, and polish his playing technique.
Sloppy technique may pass unnoticed in an acoustic environment, but pickups have the "annoying trait" of picking up everything.

I often make amps for acoustic instruments and hear complaints such as: "my shirt/pullover sleeve makes a lot of noise brushing against the soundboard", "my belly buttons scratch the back of the guitar and make annoying noises", "I tune my nylon strings guitar and hear a squeaky noise while tuning it" and so on, similar to noob electric guitar players who complain "I stop touching the strings or bridge and the guitar hums".

All those noises are acoustic in nature (except the last one) and pickups just do their job.

Answer is to polish technique and not need noise gates, compressors, peak clippers, just to be able to play.

Again: pickups are incredibly sensitive and catch, not only Music, but all mechanical noises and treat them with the same respect, so players must be VERY careful about that.

Agree that cutting some low end may help.

The unique violin body set of vibrations and resonances, optimized for what the music strings put out, "naturally" filters out many "mechanical" noises simply by not reproducing them.
Just throwing a random number on the table (should check a violin's lowest string frequency) , say that it reproduces down to 200/250 Hz and below that it falls catastrophically, wouldn't be surprised at 18 or 24 dB/oct ... while a piezo pickup may be flat down to 30 or 50 Hz .

I made a combo for our Rock/Blues violin player, Jorge Pinchevsky, with 2 x 8" + tweeter, 100W RMS, flat equalization, limiter to avoid distortion and sharp cut under 200Hz.

A free sample:
https://youtu.be/h5aV_SIiINE

[Leo_Gnardo]

The most simple one I can think of (and least "invasive") is from Ampeg SVT4Pro preamp. However since the amp has 0 db input sensitivity using a voltage divider as per Ampeg schematic will make it less sensitive.
After some more thinking that thing must be very fast in order to take the peaks down and those Vactrols are not that fast.

Drive a FET instead from that op amp circuit. I reckon you could leave a LED in place where the Vactrol's is, it'll blink to let you know when it's operating, and drive the FET gate from the junction of that LED and the diode going to ground. Way faster than any ol' Vactrol and cheaper besides. Now which FET to use... any suggestions folks?

Enzo, there's grease for squeaky strings too. "FastFret" and a couple other brands, you could use WD40 in a pinch. Or just play after you've been eating fried chicken, that's worked for many a musician.

noob electric guitar players who complain "I stop touching the strings or bridge and the guitar hums".

I have a minister with 50 years of guitar experience who preaches while strumming his Telecaster. His complaint, exactly that, "buzzes when I let go." Won't take advice from his friends with similar experience "Yes, they do that." Noob forever? Maybe if he got a note from the Pope - "Yes my son, they do that, get over it." (Put smiley thing with angel wings and halo here.) Yes it's properly shielded, for some reason he won't dial down the volume or use a mute button or wireless rig. Go figure... need some divine intervention, help!

OK minor hijack over, back to our clacky violinist already in progress.

[Chuck H]

If the guy never noticed it when playing acoustically then there IS an effect from the pickups, amp, volume, whatever that is being accentuated. No reason to NOT tackle it at face value rather than a change in playing technique (IMHO). I might try running the instrument through a multi band EQ to the amp and see if reducing any specific frequency/ies reduces the problem. Then the amp can be tuned to filter just those problem frequencies a bit. More likely the problem is the pickup. Try running the instrument with a clip mic into the amp rather than a pickup. Does the problem still manifest? If not then the problem isn't the amp, it's the pickup. And on that note (no pun intended) a lot of electric violin players WANT all the string noise for effect. They play overdriven tones and a lot of plectrum styling and such. This might be a reason why electric violin pickups may accentuate these things, as well as bow noise when the stroke is shifted. But that's just me thinking out loud on the matter. I have a little experience with amplified cello. Same thing. Those guys want every nuance, tick and bump to come through loud and clear. And THAT sort of playing DOES require refinement of playing technique. If it's just the sound of an acoustic violin your guy is after, he should be using a simple mic arrangement.

[Gregg]

Thanks for all your suggestions. I'll try them one at a time.

[gui_tarzan]

Yes, adjusting his technique will probably fix his problem. I have a tendency to pull my bass strings down with my fingers when I pluck them, resulting in a noticeable click. Adjusting the angle in which I pluck fixes the problem - every single time. But as far as the string noise Enzo, that's the ridges in your fingerprints sliding across the wound strings. The trick there is to use a very light touch which in most cases requires lowering the action and forcing yourself to use lighter pressure. It'll also help your speed.

You could change to flat-wound strings but that will just make it sound crappy.