Copyright 2008

My amplifiers and speakers...

1983 X100B
1993 QuadX/T100
AX-84 Hi-Octane



1983 Carvin X100B

There were a few variations of the X-Amp.  This Series III model is the early "H" revision which utilized 6L6GC output tubes.  It has a type of sound that is almost impossible to be had with today's typical modern amps.  As you might guess, this model is no longer manufactured.

Features of the X-Amp

Both drive and clean channels share the 3-band EQ, presence, and reverb.  The 5-band graphic EQ is assignable to either channel for additional coloring.  The clean channel has a pull-bright switch and the drive channel as a pull-HI LEAD switch that "opens up" the amp.  Reverb, channel switching, and a 7db volume boost are activated from the floor switch.

The drive channel has the ability to obtain "clean-type" overdriven tones at both high and low volume levels.  The clean channel has been described by my amp tech as having qualities similar  to a  Fender Bassman.  Wattage is switchable between 100 and 60 watts.

Below is a shot of the back panel of the 1983 X100B Series III head.


Need a manual for your X100 / X60?

Back in '83, this is all that came with the X100.  But hey... with
this amp you didn't need a dissertation to get a great tone.



JAN Phillips 7581A
(Military - USA)

I've got four matched NOS JAN Phillips 7581A output tubes in it right now.

These are considered the best of the 6L6GC type.  They give a nice vintage, bouncy round tone.  Lots of headroom with smooth breakup when they finally distort.

With this particular 7581A becoming rare, I went ahead and bought a matched backup set from Lord Valve.  Willie knows his tubes.

I've got a nice picture of these glowing bottles that makes a neat looking desktop wallpaper.




For preamp tubes in my X100B, I am running these new-run 12AX7EH.

They get smooth, "non-grainy" vintage sounding preamp distortion.




1993 Carvin Quad X-Amp / T100
Rack Amplifier System

This system can do it all.  The Carvin Quad X preamp has been called the guitar industry's best kept secret.  I don't know if I would go that far but if you have a certain electric guitar sound in your head, with a little tweaking you can get it with the Quad X.

My Rack Components

Preamp........................ 1993 Carvin Quad X-Amp
Power Amp................. 1993 CarvinT100 Tube Stereo
Effects Processor.....  2001 Carvin XP4
Power Conditioner...  Carvin AC120
Case.............................  SKB 6-space rack



1993 Quad X Preamp

There are four channels in the Quad X: Clean 1, Clean 2, Crunch ,and Sustain.  There are a total of nine 12AX7 preamp tubes used. 

 It's called "Tube CascadeTM" - The Quad X uses 9 tubes.

Each 12AX7 tube has two sides: Clean channels 1 & 2 use a single tube stage - each taking a side from tube #1 (V1).  Channel 3 uses 2 tubes which is 5 tube stages (V2, V3, and half of V4).  Channel 4 uses 11 tube stages - the other half of V4 plus 5 more tubes (V5, V6, V7, V8 and V9).

Quad X Panel Diagrams

Quad-X-GIF.gif (86301 bytes)

FS77.gif (8764 bytes)
(Click images for more detail)

Features include mono or stereo operation, 6 flexible effects loops, a spring reverb tank, a first-rate adjustable noise gate, cabinet-voicing simulator circuitry for direct-in, and a 5-band graphic EQ in addition to each channel's dedicated active EQ knobs.

The FS-77 footswitch controls the preamp's channel selection and reverb, effects loop and graphic EQ for each channel.

Below is a shot of the inside of the Quad-X.  The tubes designated V1-V9 and go from left to right.   Currently, I'm running all JJ Tesla.  V1, V2, V3, V4 are ECC803S.  These go to channels 1, 2 and 3.  Channel four tubes are V5, V6, V7 with ECC83, both V8, V9 have ECC832.  Channel four really came alive when I added the ECC832 tubes.

Quad X-Amp Sound Samples

Channel 4 (mic'd, no effects)



1993 Tube 100 (T100) Poweramp

The Carvin Tube 100 stereo power amp shipped with 4 EL34 output tubes and cranks out 50 watts in stereo mode and 100 watts bridged.

T100illus.gif (31345 bytes)
(Click image for more detail)

On the front are level controls for each channel, signal indicator lights, and power on-off/standby switches.  The rear panel has a stereo/bridge switch, presence adjustments and impedance selectors (4, 8, 16) for each channel.  The unit is force-cooled with a rear panel mounted fan.


For output tubes, I'm using JJ Tesla E34L tubes in one channel and Groove Tubes EL34 in the other.

I had a couple of reversible mods done to my T100 to give it earlier breakup.  On the JJ side, I had a tech wire in a master volume.  The Groove Tube side has two 390 ohm resistors wired in parallel to cut down on the output, allowing me to drive the tubes harder.

It works!

See the image below.  The modification schematic is listed below the image.


T100 Manual (.pdf 1830KB)
T100 Schematic Rev A&B  (.pdf 619KB )
T100 Modification (.pdf 92.4KB )

AX84 "Hi-Octane"
(Home built)

In 2002,  I built this tube amplifier below with my own two little hands using the schematics I got from the AX84 web site.  This amp uses the "Hi-Octane" circuit that has been perfected by Chris Hurley who runs the site.

Instead of doing the wiring using terminal strips, I bought an eyelet board from Jim at The House of Jim.  He makes them for most all of the AX84 projects.  It made the wiring easy.

Terminal Strips

Eyelet Board

Avoiding hum in an amp like this, requires some research on amp grounding and wiring theory.  Wire paths in relation to input, output and tube receptacles is important.

On the close-ups, note the white ground wires attaching to the chassis at two points (my stab at "star grounding"), the twisted heater wires and other twisted pairs.

I lucked out... mine is as quiet as a mouse.

Click here to see the insides.


This homebuilt is a FULL 2 WATTS and uses a 6n1p output tube.

This amp honestly rocks and it does it at living room levels.

It has a master volume, gain, and 3 eq's on the front.  At rear, there is an impedance switch for choosing 4, 8, or 16 ohms.

With the gain up, the distortion is thick and full but individual notes still retain definition.  With the gain low and the master up, the 6n1p saturates and gives a nice controllable grind.  There are no high-volume crystal clean sounds to be had from this one!

At 2 watts, it doesn't take wall-moving sound levels to get the output tube to saturate.  It's ideal for home use... it's still pretty loud, so I can't crank it up when my wife is home.  But when I do get to crank it up enough to drive the 6n1p, the neighbors aren't aware :)

My "Hi-Octane" sitting on top of my Jenkins 2x10 cabinet




Speaker Cabinets

2002 Jenkins JSS 210
Custom-made closed back 2x10 cabinet

This is a custom system built by Doug Holt of Jenkins Sound Shop in Wheeler, MS.  He specializes in custom cabinets made especially for guitar.

This sealed enclosure houses two different Weber Vintage Series 10-inch speakers -  one Weber Ceramic Blue Pup and one Weber Ceramic Silver Ten.  These speakers are rated at 20 watts each and have a very nice sounding breakup.

Each speaker has its own characteristic and combining these two speakers in the same cabinet creates a full range sound not normally found in a 2-speaker enclosure.  The Blue Pup has strong mids and clear highs, while the Silver Ten gives clear lows and a smooth treble response.

Other benefits of having different speakers are the added options available when recording using a close-mic on the cabinet.  Because it has a closed-back cabinet, the sound is focused and tight.

I had Doug wire it with a dual position ohm selector switch on the back - switchable between 4 and 8 ohms.



1992 Carvin V412T
Slanted/Sealed 4x12

This sealed enclosure holds four Carvin  "British Series" BR12 - 12 inch speakers.  It is wired for 8ohms and is rated at 400 watts.

I love this cabinet.  Lots of tight bass but clear, distinct mids and highs.  The angled top half adds to the sound spread.



Homemade Openback 2x12

The middle cabinet in my stack is an openback that I built  in 1983.  The top, bottom, and sides are made of 1" pine and the front and back panels are " plywood.  It is switchable between 4ohm mono and 8ohm stereo modes.

It holds two Celestion Vintage 30 - 12 inch speakers.  The design of this cabinet (or lack of) adds no color to the sound.  You hear strictly speaker and although it records well, it has limited live application use by itself.  But when attenuated and run along with the 4x12, it can add a lot to the amp's overall sound.

Manuals - Schematics

X-Amp Series III

X100 - X60 Instruction Manual 6L6 version
X100B Series III Schematic Revision H
X100B Series III Schematic
Revision H3
Zipped GIF 
Zipped GIF 

Quad-X Preamp

Quad X Manual
Quad X "Non-MIDI" Schematic Set
- '92 1/4" MIDI
Quad X "MIDI" Schematic Set
Zipped GIF
Zipped PDF

T100 Stereo Poweramp

T100 Manual
T100 Schematic Revisions A & B
Zipped PDF
Zipped PDF