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Saturday, 12 August 2017

More pedal power for my rig

One of the most recent pedals to be added to my arsenal is this clone of a 1970's op-amp Big Muff.

I completed this pedal some months ago, and I had started working on it a long time before that. But I stalled its assemblage at the point when I decided that I wanted to make a couple modifications to the build, and couldn't immediately do so.

I had soldered in the two IC chips / op amps, yet then decided I wanted to make one of them removable so that I could try different op amps in its spot. Different models of op amps produce different slightly tonal characteristics.

pictured - an op amp

For example, I think that the only difference between the original op-amp Big Muff and this recent modified clone of it:

... is that the original uses the RC4558 op amp chip, whereas the Eye See Pi modified clone of the original uses an BA4558 op amp chip, which I think gives it a bit darker of a sound, and slightly different distortion characteristic.

So, I decided to remove the relevant op-amp and to install an IC chip holder that I could install in its place and then swap different op-amps in and out of. And I destroyed the original op-amp in the process - which didn't surprise me, and also wasn't a big deal since I already had to order the IC chip holder and other op-amps I wanted to use, anyways. I just ordered another of the original op-amp along with those other things.

The other modification I wanted to add to the pedal is a mid frequency-scoop switch, like there was on the original op-amp Big Muff pedals, and also like there is for that Eye See Pi pedal. The Big Muff has a pretty large mid frequency-scoop by default, and the switch gives an added option to take most of that mid-scoop away. I think the switch should be included in the pedal kit by default, since it was part of the original production run (though not the later production run), and I've personally found the modified no-scoop setting to be the one that I'm using a lot more.

Installing the switch was pretty simple, and just required a precision drilling of a 1/4" hole to fit a toggle switch through, and a couple of wires and resistors to connect each side of the switch to the pedal's PCB. I also placed some electrical tape between the switch components and the PCB.

So, I had this pedal sitting in a semi-completed state on my desk for probably many months until I decided to initiate those modifications - and then I finished it up quickly.

dramatic re-enactment of the alleged desk (actually, just not cleaned up yet at the time of its photographic capture)

There was a problem with the pedal when I was first testing it out, being that the emitted sound would not stay entirely on while the pedal was engaged, but would flicker on and off. So, I opened up the pedal again, and looked for shorts, particularly where I'd installed the mid-scoop switch. But found nothing wrong there.

However, I noticed large amounts of flux residue around the potentiometer leads, which can cause a short, so cleaned it away using isopropyl alcohol-soaked Q-tip / cotton swap / cotton buds, and, thankfully, that solved the issue. Since then, the pedal has operated perfectly.

After testing out the 3 op-amps I ordered, RC4558, BA4558, and BC4558P, I've ended up keeping in the original RC4558. Of course, I can swap it out for one of the others at any time.

C~ Soundscapes

Wednesday, 2 August 2017

Skies of Tatooine / renewal of the ATA case

Tatooine, or Earth's sky?

It's the sun shining through forest fire smoke. Just one of the effects of wildfires in BC, Canada. As can be seen, there're no fires close to where I live, which is in the Vancouver area, but it sometimes happens in summer that there's so much smoke made by fires in the province that the wind blows a lot of it into the valley areas around Vancouver.

I wish I would be posting here more, but I've said that before. I guess it'll happen when it'll happen - and I'm still working towards my music goals as I'm able to. It's cool that so many people check this blog daily to see what's up, though.

Well, so here's some of what I'm up to, music-related wise.

I've FINALLY got my Mesa Strategy 500 power amp in to an amp tech who will install them for me, along with its bags of replacement capacitors. My record with music gear servicing seems to be that there will be an issue every step of the way, and that held true when I ordered the capacitors for my power amp from Mesa, and some of the ones they sent me were wrong and not what was ordered and so I had to wait another 2 weeks for the replacements, which were then the right ones... and it held true again, today, when I dropped my amp off at a very reputable amp service shop, and the technician called me an hour later to tell me one channel of the amp that I have used regularly up until yesterday wasn't working, and asked me to come in and take a look to confirm for myself (a liability thing) - but it turned out that the tech simply didn't realize that there are independent on-switches for each channel.

At least both of those things resolved towards the positive.

However, I still don't have my guitar back from the luthier. "Should be ready this week" - last week. Should be soon, though. The guy takes on way more than than he can do, and keeps putting mine last, because it was a non-monetary deal, but also because a lot of his other serving business is with local music stores, and he wants to stay always on time with them. BS, all the same, that it's taken this long, but I'm not going to push to get it back with a sub-perfect job done on it.

I'm still playing other guitars, and my amp gear has increased considerably in the last couple of years. I've now got a lot of rack gear that I'm stacking rack gear on other rack gear because I don't have rack space for it all... or, at least that was the case until I bought this used 20U rack to put all my rack gear into!

And the only things stopping me from doing to immediately are that the old foam in it is disintegrating, and also smells absolutely rancid.

So far, I've coated the disassembled and mostly-foam-removed rack 3 times in white vinegar, and also sprinkled it with baking soda - two things which are supposed to remove odours. I guess it's worked some. Most of the rancid odour is in the old foam, which I haven't finished scraping the glued parts off, yet. I'm using a hair drier to soften the glue, and a scraper thing to scrape it off.

Once that's done, I'll order replacement foam from somewhere, and glue it into place, probably with 3M 77 spray.

I'm also going to polish its rack rails to remove the corrosion that's there and make em shine again / for the first time I'll have seen it.

I got the rack for very cheap, so it'll be worth putting in the work to make it look and smell pretty OK again - hopefully even better than pretty OK.

As for what the contents of the rack will be once it's ready to have gear put into it, I think the ordering might look something like this:

Korg DTR-1
Furman conditioner
TC Electronic 1140 Parametric EQ
Digitech DHP-55
Digitech Valve FX
Marshall JMP-1
Alesis 3630
Alesis 3632
pedal shelf
Voodoo Lab GCX
Voodoo Lab GCX
Furman conditioner
TC Electronic 1128
BBE 462

Strategy 500 power amp - in its own rack for closeness to the amp, and because it weighs probably more than half of what I do.

That device ordering is not entirely the same as what the connectivity routing will be. Though, for the most part, it's ordered according to what runs into what.

C~ Soundscapes