bassmachine2112 Posted January 13, 2014 Share Posted January 13, 2014 Hiho,here,s something that,s been buggin me for a while. Presence-what is it ? I have an old valve amp which is a Selmer treble n bass and a few pre amp pedals which have treble .bass and presence. What is presence,is it a high mid filter of some sort or a pre set frequency to boost/cut.What frequencies do they usually work on ? Just nosey but I like Presence.I like the album as well. Quote Link to comment Share on other sites More sharing options...
JapanAxe Posted January 13, 2014 Share Posted January 13, 2014 I have a Treble'n'Bass too. The presence control (both on this amp and generally) is usually a global high pass filter that works on the power amp. It controls the negative feedback for the treble part of the signal - more negative feedback, less treble to the output. Quote Link to comment Share on other sites More sharing options...
bassmachine2112 Posted January 13, 2014 Author Share Posted January 13, 2014 It,s good presence is,I ike it a lot. so it,s a high pass filter It,s independant from treble then ? Quote Link to comment Share on other sites More sharing options...
0175westwood29 Posted January 14, 2014 Share Posted January 14, 2014 [quote name='bassmachine2112' timestamp='1389642465' post='2336512'] It,s good presence is,I ike it a lot. so it,s a high pass filter It,s independant from treble then ? [/quote] Yeh id imagine so it will seem like its boosting the high as its cutting the lows Andy Quote Link to comment Share on other sites More sharing options...
6v6 Posted January 14, 2014 Share Posted January 14, 2014 (edited) Presence doesn't cut lows, and the control itself is not a high pass filter (I think JapanAxe was referring to how the control works, but that is probably just confusing unless you understand how negative feedback works) You can think of it as a treble control for the power stage of an amp, whereas the treble control itself works only on the preamp. The frequency response of the controls are similar in many amps, but the way they interact with the amp and speakers is different, particularly in a tube amp at high volume. For tube amps the presence control is interesting, because it means you can make the power amp have more gain at high frequencies, which means you can dial in more power-amp distortion for highs by turning the control up (this can be interpreted as "bite" or "chime" depending on the amp and other settings), and this response interacts with any nonlinearity in the power amp and speakers in a different way to the treble control (which mostly just adds highs without affecting the response of the power amp, or the "feel" of the amp for want of a better description). Edit: paragraph Edited January 14, 2014 by 6v6 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.