This is what the old girl looks like right now :
Now it’s not going to matter one bit if I don’t do anything about the looks, but it would be nice to get her cleaned up. There is no way I am going to be able to clean around the silk-screened lettering or [...]
Entries Tagged as 'Amp mods'
Skylark Rebuild : Last things first
December 6th, 2009 · No Comments · Amp mods, Skylark Rebuid, Uncategorized
Rebuilding a Skylark
November 28th, 2009 · 2 Comments · Amp Repair, Amp mods, Gear, Skylark Rebuid
Regular readers (hahaha…. I kill me) will remember that I bought two Gibson Skylarks. One of which I fixed immediately and the other sat waiting. This is a story about the other.
This is a Gibson Skylark in the “Crestline” series. It is one of the many amps released with the GA-5T model number. This [...]
Tags: 753397
Real McTube : We have Power.. again
May 9th, 2009 · No Comments · Amp mods, McTube
This time, I have done most of the job (I’m missing a pilot light but I’ll add that later.)
As you may recall, I chose to break out the power supply because I thought it might be useful in other cases. In fact, if I were to mock up the preamp of the Crestline Skylarks (130V [...]
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Real McTube : Some Notes on Rectification
March 29th, 2009 · No Comments · Amp mods, Gear, McTube
The Real McTube II was designed with rectified filament voltages because Fred found that the original McTube could be noisy if not done impeccably well. The original McTube (appearantly) had the 12 V AC from the transformers going directly to the heaters on the tube.
That is the way it’s always done on the old amps [...]
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Songbird : Requirements II – Pre Amp Bias
December 13th, 2008 · 2 Comments · Amp mods, Gear, Songbird
Ok, so clean power and rectified heaters and some other stuff were covered in the previous requirements post.
Tube Biasing – 1st Stage
As I understand it from my readings, the standard way of biasing, self biasing, is a complex reaction. Essentially as the power drawn from a tube increases, the bias goes more negative, somewhat [...]
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Songbird : First things Second
November 30th, 2008 · 1 Comment · Amp mods, Songbird
I guess before I dived into the requirements, I should have talked a bit more about the amps upon which I am basing the Songbird.
Unsurprisingly, I am starting with a Gibson Skylark. To be specific, I am starting with the pre-crestline GA-5. This is a lovely little class A, single ended amp, rated [...]
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Songbird : Getting Started (Requirements)
November 27th, 2008 · 3 Comments · Amp mods, Songbird
The Songbird is the next project for me, after / along with the Real McTube.
The major goal of this project is to get me a Champ/GA-5 (Pre-Crestline) style amp for far less than the 500 or so for an original. I don’t like any of the re-issues, both the Gibson and Fender re-issues [...]
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Mods to the working GA-5
January 27th, 2008 · 5 Comments · Amp mods, Gear
Of course I’m gonna mod it, this ain’t a museum!
I’ve already done my 3 prong conversion, but now it’s time to make this thing more fun. Reminder for those reading along in sequence: I have two GA-5’s, one of them is the project that is not yet working and the other [...]
Tags: Attenuator·GA-5·Gibson Skylark·Mallory·Mods·T8