[2721] AKM factory fire

Date: October 31st, 2020 | Comments : none | Categories: DIY.

The semiconductor maker Asahi Kasei Microsystems (AKM) had a massive fire at its factory that essentially wiped it out.

How does this impact fx pedals? AKM audio codec chips are widely used in high-end digital effects pedals. The AK4556 is one such chip.




[2719] The Underdrive

Date: October 30th, 2020 | Comments : [3] | Categories: DIY.

I never knew this was a thing until I saw a forum post about it this week. Apparently it is the anti-boost, which means that the output can only be attenuated. Sounds easy enough… a potentiometer and switch in a box will do the job but can lead to loading problems and tone loss, so I quickly designed this circuit:



[2716] CMOS Cookbook

Date: October 26th, 2020 | Comments : [1] | Categories: DIY.

I have a paper copy of the 1st edition of the CMOS Cookbook that I used so often that the pages started to come loose from the binding. It is an essential resource for anyone who wants to work with CMOS chips.

The author, Don Lancaster, has made the 4th edition of CMOS Cookbook available for free download from his site. Get it immediately. Thanks Don!


[2713] CA3080 OTA

Date: September 19th, 2020 | Comments : none | Categories: DIY.

Several vintage CA3080 chips that I plan on using for some new projects, including a Ross/Dynacomp clone for testing purposes.


[2711] Premier Guitar article

Date: September 17th, 2020 | Comments : none | Categories: DIY.

I got mentioned a couple of times in an article in the recent issue of Premier Guitar. Read the article here.

Thanks to Aron Nelson and Tzvi Gluckin for their kind words!

AMZ is the oldest continually published pedal site on the Internet.


[2707] 25 Years!

Date: August 18th, 2020 | Comments : [3] | Categories: DIY.

This month marks 25 years of continuous publication of the AMZ web site, though in the first few years it was called DMZ.


[2704] Free Download (again)

Date: June 5th, 2020 | Comments : none | Categories: DIY.

Another free download, this time from Hans Camenzin who invented the 555 timer chip! The book is called Designing Analog Chips and is available as a free download from the author.


[2702] Tweed Stack and SSM2166

Date: May 9th, 2020 | Comments : none | Categories: DIY.

The Tweed Stack and SSM2166 compressor circuit boards are back in stock and available for immediate ordering. Check it out!


[2701] Ibanez MT-10 Mostortion

Date: May 9th, 2020 | Comments : [1] | Categories: DIY.

It is possible to make an overdrive on the SoS pcb that has most of the important characteristics of the Ibanez MT-10 Mostortion. It will not be an exact duplicate but the essential characteristics are present.

I have added the parts list and instructions to the support page for the AMZ SoS pcb.


[2699] Free Download

Date: May 6th, 2020 | Comments : [1] | Categories: DIY.

Free download from the publisher:

Practical Electrical Engineering

Authors: Sergey N. Makarov, Reinhold Ludwig, and Stephen J. Bitar




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