HifiZine
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Truth and Corruption

Amp II: Corruption

After owning the first Simple SE amp for a while, I was hooked. As a matter of fact, I loved it so much I decided I needed to build another one of these bad boys. Since the first one was the “Truth,” this one is “Corruption.”

I wanted to make something totally unique so I incorporated spalted maple, which is wood that has been corrupted by either disease or some sort of infestation. This amp operates in triode mode only – the first amp has a triode/ultra-linear switch and a cathode feedback switch, but I preferred triode operation by a wide margin so I saw no reason to incorporate UL or CFB. Parts used for this build:

• Silver/copper wiring throughout
• Jensen copper foil paper-in-oil coupling caps
• Oversized Edcor output transformers
• Hammond (Allied) power transformer
• Hammond choke
• Panasonic electrolytic capacitors
• Takkmann resistors for the audio section
• Ceramic gold-plated tube sockets
• Acme Audio fuse holder and IEC socket
• Star grounding to the IEC socket
• Oversized HEXFRED rectifier diodes
• WBT NextGen copper speaker connectors and RCA sockets
• Cryo-treated Cardas home-made twisted pair / mesh shield internal signal cable wiring
• Bolder Cable Nitro interconnect cables, speaker cable, and power cable
• Daiku Woods custom-made box

As for Truth, I asked Cal to make me a custom wooden box, and he definitely outdid himself on this one! When I saw the picture he sent me of it, I was in awe – the sides are made of spalted maple and the framing is done in walnut. (See slide show for more detailed images.)

The assembly of this amp was done in two days. That is a huge difference from the Truth, which took almost three weeks! Experience matters for sure when doing something like this, and using the other amp as a reference greatly reduced my assembly time. Once again, Wayne Waananen was kind enough to let me use his garage and tools. I was much more accurate this time with the hole drilling – not that last time was bad, but it was 5-10 mm off at times, which is enough that you can see the hole when using EL34s. This time the holes were within a millimeter! When the tubes are in you can’t even see the holes – except of course for the signal tube socket which is impossible to hide.

Concluding remarks

I have owned these amps now for several months. Like any amp, there was an extensive break-in period, although by no means the worst break-in experience I’ve ever had. Once they started to calm down in treble energy (about a month and a half), they started to sound very full-bodied and image like crazy. The soundstage is deep and wide – depending of course on the material you feed them. There is a robustness to the sound that I have yet to hear from any other amplifier, whether it be push-pull, OTL, or any other topology.

Note: I am contemplating building another one of these and sending it out on tour. Please let me know if this is something that you may be interested in. Remember that this is a 5-watt triode / 15-watt ultra-linear single-ended amplifier, so you cannot just hook it up to some Wilson Watts and expect 110 db output. But if matched properly to a set of moderately high-efficiency speakers you’ll be in pure bliss with the sound. Please let me know in comments below if you are interested.

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