Guitar companies are making models for the masses while the instruments artists play are typically modified to get special tones in the instrument rather from amps or software (see the 'Schematics' page). All companies have custom shop brands or options where you can get this done for $5 - $10 thousand +. Since 2008 a lot of info has been available on the internet revealing schematics and modifications to get the artist tones. This opens the window to have special instrument tones in your guitar or have a mod guitar that has the features of a $$ custom shop model. This blog will pick a few projects to get classic tones and increased flexibility on board. Not for everyone but it is a matter of style, understanding what goes into a custom shop $10 thousand guitar and why great players use a hand full of onboard modifications to trademark their sound.

Second Hand -"It's probably a well-known story . . . I went into a shop in Nashville called Sho Bud which was owned by Buddy Emmons – the famous pedal steel player – and they had things like Rickenbackers in the front of the shop going for quite high prices. In the back they had this second-hand department, and there was a row of Stratocasters, and I bought them all. Blackie was made out of three of these guitars – the body of one, the neck of another and the pickups of another." Eric Clapton



Power Attenuator and Other Boxes

Boxes- Power attenuator, series connector for speakers

Power attenuators (also called tube soakers, hotpads) are used to lower the speaker volume without adjusting the volume or master controls on a tube amp.  I dont think they are widely used since most people dont mind turning down the amp if they are inside and can not play loud but the tone quality changes dramatically as the amp volume and master controls are cut back. If you normally play with a clean tone it does not matter but if you like the sound of saturating the power tubes and like the distortion but this makes the amp much to loud to play then the attenuator helps. It will let you play with tube distortion without waking up the neighbors.

 The cheapest ones I could find online were about $40 without a bypass switch.  The parts to put one together was less than $20 with the attenuator from Parts Express for $10. (Speaker L-Pad Attenuator 50W Mono 1" Shaft 8 Ohm Part # 260-255). 


 The attenuator goes between the amp and the speaker and splits off a portion of the power sent to the speaker while looking like a constant 8 ohm impedance to the amp. The amp can maintain the high power to saturate the tubes while you lower the volume after the amp using the separate attenuator control. The power that you are splitting off gets dissipated as heat so the box can get hot.  Additional info for this project is at this link including a demo video and this was my only reference:
http://guitarprojects.weebly.com/diy-attenuator.html


Schematic from 'Guitarprojects' 



The Blues Junior project added a lot of clean headroom to a 15 watt amp and juiced the volume with a new output transformer. You can get low volume distortion by turning up the volume control all the way saturating the preamp tubes then keeping the master control very low.  This gives a small range of low volume distortion.  Using the attenuator worked great with this amp to get all the tube tones at low volume.

 This issue of tone changes with low volume is only a big deal for tube amps.  If you are using solid state amps or digital effects then they can just be slightly tweaked at lower volumes and you are good to go. 

 Lower volume in both tube and solid state amps will have some tone effects from the lower power being sent to the speaker so some adjustment may be needed to compensate for speaker characteristics when using the attenuator and this usually means adding treble/brightness which is why a bright switch is included in the circuit.






Series Connector for Speakers



I have a lot of 8 ohm single speakers or cabinets with 2 speakers that are 8 ohm wired in parallel giving a 4 ohm cabinet.  My amps have connection jacks that are wired in parallel to the main speaker jack so it would be helpful to setup series and parallel speaker connections.

 Parallel connections are easy with Y-cables but series connection cables are harder to find and expensive.  The easy fix is a simple box with 2 input jacks and 1 output jack wired for series connection.






Speaker Wiring 


Options for different impedance  

Wiring for 4/16 ohm switching
but this does not allow playing single
speakers
Switch wiring close up




Three jack option using switched
jacks in addition to DPDT switch
















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