Have Been Out of Circulation--Just Got Back

[David Root]

Just wanted to say Hi again. I just spent almost four months in hospital, now convalescing at home. Still pretty weak after six weeks rehab.

Still, I can't complain. June 7 I had surgery for carcinoid liver cancer. Fortunately it is a very slow growing form, as I was diagnosed some six years ago.There were some complications, I got pneumonia and it took several weeks to fix. but the surgery was a success, I'm free of it now.

Will be a while before I can get back to amp building. Before I went in to hospital I bought a bunch of vintage parts to try my hand building reconstructions of old pedals. I started a Dynacomp using an original '77 PCB I got here on TAG. Bought a '74 Phase 90 on E-Bay so I know exactly what they look like inside. Lots of pics on E-Bay too, MXR used whatever was cheapest I think as there are lots of variations in parts. Will also try some of the other classic pedals.

So, another old guy with a new lease on life!

[John_P_WI]

David,

So sorry to hear of your troubles but very happy to hear the positive outlook. Take care and here is to a speedy and full recovery.


John

[xtian]

Good news! Welcome back!

[tribi9]

Good to hear you're staying positive.

[LeftyStrat]

Sorry to hear about your illness, but congratulations on the successful surgery.

Here's a get well soon card. I bought it new around '77. Lost the case, at one point I had it mounted in my guitar

Let me know if you need any values measured.

[stelligan]

Welcome back! Here's to continued better health.

[David Root]

Thanx to all for your good wishes! I still have probably three or four months before I can go back to work full time. I plan on retiring middle of next year anyway.

Lefty, that Dynacomp was probably made before '77. The '77 boards I have are set up for the later 8-pin plastic bodied IC , the metal can is earlier. Those green ceramic caps and color coded dipped tantalum caps I've seen on '75 models, and they are also in my '74 Phase 90.

[Cliff Schecht]

David, it's really nice to hear that you are out of the hospital and doing better. Your presence around these parts was missed .

Also, thanks again for even bothering to respond to my email about the post-phase-inverter driver stage a few months back. I *finally* got that quad KT120 amplifier together (I guess the SSS idea went out the window eventually) and it sounds fantastic. I left out the PPI driver because I kept getting stuck at that point in the amp (and in the layout) and needed to get this off my bench, but I'd like to mess with this circuit for my next big bass amp build (probably in early-late 2013).

I have a couple of those Dynacomp boards too and want to get them built. I'm curious how you find the performance (noise, sound quality) of the Dynacomp when built to early specs. Are you considering a Ross clone as well?

[David Root]

Thanx Cliff! My SSS 001 has the direct coupled cathode driver and it works fine with minus 175V raw bias. minus 51.5V on the cathode grids and minus 50V on the power tube grids. Power tubes are Mesa 415 STR. 7581A. It is very loud, great for a bass amp.

The Ross Dynacomp mod is on my list, it's relatively simple, I just want to start with the original Dynacomp.

[LeftyStrat]

Lefty, that Dynacomp was probably made before '77. The '77 boards I have are set up for the later 8-pin plastic bodied IC , the metal can is earlier. Those green ceramic caps and color coded dipped tantalum caps I've seen on '75 models, and they are also in my '74 Phase 90.

Oh yeah, I graduated high school in '77, and I remember having it before I graduated, so I probably did pick it up around '75 or so.

It's a great circuit. With the compression control down it acts more like a transparent boost, and unlike some compressors, the volume increases as you turn up the compression. It could probably work quite well in a rocker pedal controlling the compression. You can hit a note and bring up the compression and go into infinite sustain/feedback, even at lower volumes.

[martin manning]

Welcome back, David! Glad to hear you are now on the right side of it.

I built up one of those vintage Dynacomp boards from ChrisG last year. I had no problem putting a TO5 can CA3080 into the 8-pin DIP board, and I believe I used small Panasonic 50V film caps instead of ceramics. Otherwise its the original MXR, and it sounds great.

[David Root]

Thanx Martin!

I have an assortment of the TO-5 CA3080 and one is on my board already, a '71 RCA. I also have 40 of those green ceramic caps, made in Mexico, same as the originals. I am mounting the IC and the transistors on sockets so I can try different ones, see if it makes any difference. Probably not, but you never know!

[Deric]

Welcome back!!!

[M Fowler]

Get well David.

I also have a board I bought a while ago and plan to get it built one of these years.

Mark

[amplifiednation]

David, great to have you back. I hope you are feeling better!!!