[1827] Keeley Oxblood

Date: September 5th, 2015 | Comments : [1] | Categories: DIY.

New Pedal Day! Jamming on my Oxblood Overdrive while wearing my Keeley Electronics t-shirt:

Keeley Oxblood Overdrive


[1818] Gear Guys Radio Show

Date: August 27th, 2015 | Comments : none | Categories: DIY.

Woohoo! Got a shoutout from Robert Keeley on a recent episode of Gear Guys Radio! Thanks, RK!

Update: Also got some props on RK’s web page for the new Oxblood Overdrive


[1811] 20 Years!

Date: August 3rd, 2015 | Comments : [8] | Categories: DIY.


This month marks 20 years of continuous publication of the AMZ web site, though in the first few years it was called DMZ.

I launched the first web page in August 1995 when the first AOL members web storage spaces became available. You may have seen the http://members.aol.com/jorman/ web address on a few on my very old schematics. At the time, there were only 23,500 web sites on the entire Internet and there was only one other fx pedal related site called Leper’s Abode, but it was only a collection of a few schematics.

The latest Windows version then in common use was 3.11 though Windows 95 launched later in the month. There were plenty of DOS machines still in use too. It was a much smaller and more limited online world in those early days, and no web stores! You had to get paper catalogs to order from Digikey or Allied Electronics and call them on the phone to place an order — landline phone: most people didn’t have a cell phone as they were very expensive and quite large. They would not fit in your pocket yet.

The muzique.com domain name was registered in March 1999 and I moved the web site from AOL to the new server, where it has been since.

I hosted two fx forums over the years with the last one only shutting down when the free web forum service closed. Around that time, two new effects forums opened, including Ampage (created in 1999) and DIYStompboxes (created in 2001).

I’ll update this with more info as I look through my archives.

Jack Orman
3 August 2015


[1777] Tone Report Issue 70

Date: April 10th, 2015 | Comments : none | Categories: DIY.

Tone Report 70

Tone Report Weekly Issue 70 mentions my Mosfet Booster in their Ultimate Clean Boost Buyer’s Guide (page 10). Many thanks to the Tone Report crew for their kind comments!


[1769] Gearphoria

Date: March 21st, 2015 | Comments : none | Categories: DIY.

Gearphoria magazine

My website was mentioned in the March/April issue of Gearphoria magazine in the Workbench Confidential column by James Lebihan (of Mission Engineering). You can read the article online on the Gearphoria web site. Thanks James!


[1766] Fuzz Face Calculator

Date: March 18th, 2015 | Comments : none | Categories: DIY.

Fuzz Face schematic

This calculator is used to determine resistor values for the basic fuzz face circuit to set the desired DC operating point.

Go to the Lab Notebook and try it out.


[1761] Big Muff Calculator

Date: March 18th, 2015 | Comments : [3] | Categories: DIY.

Big Muff schematicThis calculator is used to determine resistor values for the basic shunt feedback transistor circuit to set the proper DC operating point.

Very useful in converting BMP gain stages to use germanium transistors.

Go to the Lab Notebook and try it out.


[1755] Calculate Slew Rate

Date: February 20th, 2015 | Comments : none | Categories: DIY.

How Fast Does your Opamp Need to Be?

slew rate of lm308

This calculator is used to find the slew rate needed to reproduce a signal at a specific frequency.

For example, the 0VU level of the -10dBV signal used in most semi-pro equipment is 0.894v p-p. We use this value with the maximum frequency that will be passed through the circuit. Try 20,000 Hz as an example.

The +4dBu signal is 3.47v p-p and you can use the calculator to find out how much faster the amplifier needs to be to push this higher signal level.

The Rat pedal opamp would need to slew about 8.0v at 10kHz. Find the slew rate needed for the opamp.

In the Lab Notebook at http://www.muzique.com/lab/slew.php.


[1744] PAM8403 Class D Audio Amplifier

Date: January 24th, 2015 | Comments : [1] | Categories: DIY.

PAM8403 Class D Audio Amplifier



[1730] AC125 Germanium Transistors

Date: January 22nd, 2015 | Comments : [2] | Categories: DIY.

ac125 transistors

I have a limited number of AC125 PNP germanium transistors available.




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