On Feedback, Good and Bad
In this article, Pete Biltoft at Vintage Vibe Guitars describes the various causes of guitar feedback, both good and bad, and provides some suggestions for eliminating unwanted feedback.
Thanks again to Pete for the permission to post this here!
June 2013
Howdy!
Feedback: when it is used in an appropriate, controlled manner it can be glorious; when it appears unwanted it is about the worst sound ever. In this Tech Tips newsletter both types of feedback will be discussed.
Let’s start with the undesirable out of control high pitched screech we want to eliminate, and then move on the good stuff.
Unwanted microphonic feedback in guitars with magnetic guitar pickups usually arises from one or more of the following sources listed below. With each of these sources I have added suggestions in italics for eliminating the associated feedback.
Vibration of the coil windings inside a magnetic pickup. Most modern pickups are potted in molten wax under vacuum to reduce the possibility of unwanted microphonic feedback.
Les Paul’s Estate Auction
Lester Polsfuss passed away at the age of 94 after a fight with pneumonia on August 13, 2009. Nearly 3 years later, the property from the estate of Les Paul went up for auction in Beverly Hills, CA.
The auction company put together a beautiful 400 page book listing the items of the estate. In case they end up taking down the book, I have saved the PDF here (68MB) for posterity.
The estate items range from the awesome, to the slightly disturbing, to the nostalgic and the just plain silly. Let’s take those in order:
- awesome: tons of guitars of all types, prototypes, design drawings and notes, amps, oscilloscopes and test equipment, electronics (pots, tubes, caps, transformers, etc), mixing desks and early multitrack tape recorders, and even some hand-cut wood acoustic wall panels
- slightly disturbing: his social security and union cards, Chase credit card, drivers license, passport, Christmas cards, and signed checks. Oh, and a white terry cloth bath robe.
- nostalgic: photos, awards, scripts and letters, the bronzed army boots that Les was wearing when he met Mary Ford, and his gloves and glasses. Ok, also slightly disturbing!
- just silly: $400 of used picks, a New York state license plate reading Les Paul, a signed vegetarian cook book from Linda McCartney. Lots and lots of turtleneck shirts. Apparently the license plate sold for $10,000!
- I don’t know where this fits- but a top-hat given to Les Paul by Slash (Valued at $6000-$8000! Hah!)
Man, did Les Paul have an amazing guitar collection!
In addition to the gorgeous specimens from Gibson and Epiphone that you would expect, you’ll also find lot 722- a 1951 Fender No-Caster signed by Leo Fender (valued at $40,000-$60,000). It actually sold for $180,000 (!) as documented in this handheld video from the auction floor. That’s some kind of crazy, right there.
A Little Love for the Les Paul Tribute Plus
After nearly a year, I’m still loving my Epiphone Les Paul 1960 Tribute Plus. I‘ve played a number of gigs with it and it has proven itself absolutely reliable and roadworthy. It has really excelled in every situation – loud indoor gigs, scorchin hot outdoor summer gigs, and of course my everyday practice, both unplugged and amplified.
This model seems to be a diamond in the rough at Epiphone- a truly great collection of features, including the awesome Gibson ‘57 Classic pickups, for a very competitive price.
I’ve often wondered why I haven’t seen Epiphone really promoting this model as much as it deserves. Well today, I noticed that it’s currently featured on the front page of Epiphone’s website, as part of their 140 years (1873-2013) anniversary. There’s a nice write up with a few choice quotes from Les Paul, and some gorgeous pictures.
Maybe they’ve finally decided to seriously promote this gem of a guitar!
New Amplitube iRig HD interface
In my series on building your own iDevice Guitar Interface, I demonstrated an interface which connects through the headphone/microphone jack. This is similar to the commercial products like IK Multimedia Amplitube iRig, Peavey AmpKit Link, Griffin GuitarConnect. And like all those, it works well, but it is not the most high-fidelity solution.
There are also a number of products that instead connect using the dock connector on the bottom of the iDevice, for example the Apogee Jam, Sonoma GuitarJack, Alesis iO Dock and Line 6 Mobile In. These interfaces have their own A/D converters, and pass the signal digitally to the iDevice providing higher quality audio. The downside is that you can’t charge the iDevice on battery while using the interface, which may be an issue for live performance and recording.
There’s a new contender in the dock-connected interfaces, and it looks pretty nice: the IK Multimedia iRig HD. In appearance, it looks very similar to the Apogee Jam. I prefer this style of interface, rather than the Sonoma, and Line 6 approach which have the entire unit hanging off the dock – that seems very precarious and likely to break the dock.
Also, at $99 the iRig HD is cheaper than the $129 Apogee Jam. If you have a newer iDevice with the lighting connector, the iRig HD is an even better deal, as it includes the lightning adapter cables as well as the older-style 30-pin connecter, and also a USB connector for use with a computer.
All that said, I’m perfectly happy with my DIY interface for practice, but if I was using it for recording or live performance, I might consider buying this iRig HD.
Alternative Pedal Enclosures from Rixen
In pedal building, we almost exclusively see the Hammond-style diecast aluminum enclosures. You know their names- the ubiquitous 1590B (aka 1290NS) and its plus-size cousin the 125B. Then there’s the larger 1590BB, and the tiny and temperamental 1590A. What these all have in common is the simple generic rectangular shape.
But what if you’re a fan of the spring-loaded foot-pedal enclosures made famous by the BOSS and Ibanez pedals?
Typically, the only way for DIY pedal builders to achieve that look was to buy an old pedal and gut it- but then you’re stuck with the original pedal’s drilling layout.
Now there’s a new option- I just came across these new enclosures from Rixen Pedals.