I'm building a Combo Amp for someone.

The cabinet is Pine 13" wide x 15" tall and 11" deep. All glued together and used a 1/2" roundover bit in my router for the edges.

The speaker is a vintage 10" Utah 15W 8ohm. The amp is my dual Im386 chip bridged amp design. Can run on 9volt battery or walwart and output is 1 to 2 watts.

Views: 2158

Replies to This Discussion

After sanding and routing I cut a hole for the control plate on top at the back edge. Decided to burn the wood with a propane torch and finish with Truoil.

Started burning with the torch and discovered that my old torch was leaking when the whole tank and torch went up in flames. Got the fire out with blowing up and threw away the old torch. Went to Tractor Supply and got a new torch, went home and finished the job. Pics before the Truoil.

Making the speaker baffle and rear access door out of 3/8ths" plywood. Rear door will be hinged to allow access or to have open back cab sound if that is wanted.

Being an ex steel/metal fabricator, I'm use to this kind of thing happening. Just blow out the flame with a air compressor or smother the flame out and then turn off the gas. If you panic, things get worse or you get hurt.

While waiting for the Truoil to dry, I moved on to the speaker baffle. Got the speaker mounted on a 3/8ths" plywood baffle and it's time to cover the baffle. I looked over the stores that sell fabric for blue denim, but all the material I found was too thin. Kept looking and came across 2 that looked decent. One is a blue denim with a white threaded strip pattern and the other is a greenish gray solid color. Does anyone have a preference between the two?

My wife and I were leaning towards the blue one too. Got the material for 5 bucks each, store closing sale. Bye bye Hancock Fabrics.

My original circuit has 2 tone capacitors on a switch to allow a regular guitar amp tone(.047uf) or switch to a (.1uf) capacitor for a bass/darker tone. I'm removing the switch and adding a second input jack. Each input jack will have it's own tone cap(.047uf for the high and .1uf for the low) for a old style High/Low input choice. This way enables two instruments or a instrument and microphone or keyboard to be used through the same amp. Might suck a battery dry quickly, but a walwart will be fine.

The way this works is the input jack goes to a JFET-then to the switch-choice of cap-then to the volume-then to the chip.

So I have to add a second JFET-run a jack to each JFET-each JFET to it's cap-and both to volume-then to chip. Switch is deleted.

As far as electronic knowledge is concerned, I'm an amateur that knows how to avoid some danger an probably get into more danger. LOL


Lesson learned on spreading Truoil on a large surface. Thin coats is best wiped on with a folded paper towel. Brushes of whatever type soak up too much of the Truoil. Had to sand back the finish with 400 grit and reapply with the paper towel. One more coat will do it, then I'll add some pics.

Got the rear door painted Black. Have some brass hinges and hook & latch.

Need to got back to the store for some tack strips to put the grill cloth on.

Got the back door on.


Have you thought of just Velcroing the back door on? It's gonna get in the way when you build your DIY Sound Enhancer...:-)

Yeah that would be funny. A snake on a spring reverb.

Got the the controls laid out, drilled and installed. Need to find a way to label everything.

From left to right: walwart jack and 2-way switch for 9volt battery use, lighted on/off switch, 2 input jacks for HI/LOW choice, 4 pots V1 - G1 - V2 - G2 and stereo out jack for headphones with shunt for speaker cutoff.


The Essential Pages

New to Cigar Box Nation? How to Play Cigar Box GuitarsFree Plans & How to Build Cigar Box GuitarsCigar Box Guitar Building BasicsCigar Box Guitar Parts Store

Site Sponsor

Recommended Links & Resources

Discussion Forum

Ruby Amp

Started by BrianQ.. Last reply by Paul Craig Nov 28, 2019. 13 Replies

DIY Spring Reverb

Started by Kevin Keating. Last reply by Paul Craig Oct 17, 2019. 4 Replies

TDA2030A Amp

Started by Bama Hound. Last reply by Gary Stenzel Jul 23, 2017. 14 Replies

Home Brew Champ Tube Amp

Started by Scott aka Farmer Ted. Last reply by Paul Craig Feb 6, 2017. 3 Replies

Dual IM386 Chip amp

Started by Paul Craig. Last reply by Paul Craig Jan 27, 2017. 29 Replies

5 Watt Amp Kit (DIY Case)

Started by Walter Haapapuro. Last reply by Gene Jones Dec 7, 2016. 46 Replies

DIY reverb behold - I found this online

Started by Danny B.. Last reply by Paul Craig Nov 2, 2016. 3 Replies

Bass Cabinet project

Started by Murdoc_420. Last reply by Murdoc_420 Jul 16, 2016. 34 Replies

Kalamazoo Model 1 Deluxe

Started by Scott aka Farmer Ted. Last reply by Rick Alexander Jun 20, 2016. 12 Replies

LM386 amp and other stuff

Started by Denis U. Last reply by Denis U May 29, 2016. 19 Replies

Combo Amp Build

Started by Paul Craig. Last reply by Paul Craig May 27, 2016. 113 Replies

Trying to get a "bigger" sound

Started by Ian Schroth. Last reply by Blind Lemon Cello Mar 16, 2016. 31 Replies

Jana MJ-13400 Public Address amplifier

Started by Monterey. Last reply by Wayfinder Mar 15, 2016. 3 Replies

Mini-amp plans needed.

Started by Rev Mike. Last reply by BrianQ. Jul 4, 2015. 4 Replies

Will this work for an amp?

Started by Monterey. Last reply by Wayfinder May 19, 2015. 4 Replies

Radio conversion too quiet

Started by Slow Slough Guitars. Last reply by wes carl May 10, 2015. 5 Replies


Started by Truth Instruments. Last reply by Truth Instruments Apr 18, 2015. 3 Replies

Blog Posts

Neck bowing

Posted by Mike Kinzie on January 24, 2020 at 5:38pm 2 Comments

Dual lap steel

Posted by Ron Lutz on January 9, 2020 at 2:42pm 4 Comments

My 3 Gitty Kits

Posted by Poorness Studios on January 8, 2020 at 9:20am 2 Comments

My CBG details

Posted by Paul scofield on January 1, 2020 at 9:22am 2 Comments

Latest Activity

Uncle John commented on Bob Johnston's photo

20191231_111209 (1)

"Those kind of lack depth, but are still really good boxes. Pretty too. Not you, Bob. The boxes."
3 minutes ago
Derek Rose liked Poorness Studios's video
5 minutes ago
Uncle John commented on Downtown Vinnie's video

Splendor of Candor

"A very nice mood you set here.   Nice music.   Peace giving.   Get…"
6 minutes ago
Derek Rose liked Downtown Vinnie's video
9 minutes ago
Derek Rose commented on Downtown Vinnie's video

Splendor of Candor

"Refined gas fueled tuneage Vin."
9 minutes ago
Uncle John commented on Poorness Studios's video

Doesn't Remind Me

"Probably your best, Kale.  Good on yer."
9 minutes ago
Uncle John commented on Poorness Studios's video

Doesn't Remind Me

"New song to me.  I like it.  Nicely done, guys.  "
10 minutes ago
Derek Rose commented on Gary O'slide's video

Gary O'slide Univers

"Very sweet. Celtic sounding for certain."
15 minutes ago
Derek Rose liked Gary O'slide's video
16 minutes ago
Daniel Walter commented on Dave Lynas's video

The Barn Dance

"Was going for a bit daliesk. It should return to straight, neve know with these things. Thank…"
22 minutes ago
Nasty DeVille posted photos
35 minutes ago
Dennis "Denbo" Goodinson commented on Dennis "Denbo" Goodinson's photo

"BB" has a Sister

"Zulu, grazie mille!"
44 minutes ago



© 2020   Created by Ben "C. B. Gitty" Baker.   Powered by

Badges  |  Report an Issue  |  Terms of Service

\uastyle>\ud/** Scrollup **/\ud.scrollup {\ud background: url("https://storage.ning.com/topology/rest/1.0/file/get/963882636?profile=original") no-repeat scroll 0 0 transparent;\ud bottom: 25px;\ud display: inline !important;\ud height: 40px;\ud opacity: 0.3 !important;\ud position: fixed;\ud right: 30px;\ud text-indent: -9999px;\ud width: 40px;\ud z-index: 999;\ud}\ud.scrollup:hover {\ud opacity:0.99!important;\ud}\ud \uascript type="text/javascript">\ud x$(document).ready(function(){\ud x$(window).scroll(function(){\ud if (x$(this).scrollTop() > 100) {\ud x$('.scrollup').fadeIn();\ud } else {\ud x$('.scrollup').fadeOut();\ud }\ud });\ud x$('.scrollup').click(function(){\ud x$("html, body").animate({ scrollTop: 0 }, 600);\ud return false;\ud });\ud });\ud \ua!-- End Scroll Up -->