Re: [Harp-L] products

[Richard Hunter <turtlehill@xxxxxxxxxxxxx>]

"John Taylor" wrote:
<Hi. to one and all,as amember of only a few weeks I avidly read every single email put out,
however being resident in the UK virtually all the equipment is unknown to me and all the abbreviations leave me completely in the dark as to what they are and do. For example what on earth is a RP70?  what are "patches"? why hi-z inputs or low-z inputs. It is very difficult to grasp what is going on when everybody seems to think that all readers are of professional status or ability. 

John,

Welcome to the list, and kudos for your willingness to ask questions.  In order:

An RP70 is an "amp modeler", an electronic device that emulates the tone-modifying circuits of an amplifier via computer chip processing. It is used by harmonica players to modify the tone of the instrument, just like a "real" amplifier.  ("Real" in quotes because an amp modeler is "real" too, it's just very different technology.)  The RP70 is one example of this class of device, and it is made by Digitech, a well-known musical equipment manufacturer whose gear can be found at most musical instruments stores, including in the UK.

A "patch" is a specific configuration of sounds within an amp modeler (or synthesizer, or other electronic device).  The term is a carryover from the day when synthesizer programmers had to move audio "patch cables" among pre-wired connection points in order to change the sound a synthesizer made.  (This kind of terminology carryover is not unique--recording engineers today refer to the output connections on their mixing consoles as a "buss" because in the early days of recording, such outputs were made by a company called Buss.  Many of us refer to a photo-copied document as a "xerox copy" for similar reasons--it's a holdover from the days when ANY photo-copy was made by a Xerox machine, by default.  And now that I'm thinking about it, I recall that "aspirin" at one time was a brand name, not a generic term for a specific kind of pain-killer.  But I digress...)

"Hi-z" and "lo-z" are shorthand for "high impedance" and "low impedance" respectively, meaning the electrical resistance of a particular circuit, or of the device (such as a microphone or mixing board) that includes the circuit.  Resistance is measured in ohms, but we don't need to go into detail about that.  The reason it matters to harp players is that BOTH the microphone you use with your harmonica AND the device you plug it into MUST match roughly in terms of resistance (i.e. both hi-z or both lo-z), or you get a very weak sound from your gear (or none at all).

This stuff matters very little if you never play the harmonica through a microphone, or if you never want to make the harmonica sound different via electronics. Obviously, many people on this list, including me, do both.  And almost everyone on this list has played through a microphone at one time or another.

I hope this is useful.

Regards, Richard Hunter



author, "Jazz Harp" 
latest mp3s and harmonica blog at http://hunterharp.com
Myspace http://myspace.com/richardhunterharp
Vids at http://www.youtube.com/user/lightninrick
more mp3s at http://taxi.com/rhunter
Twitter: lightninrick