Recent Posts

1

Tube Amp Building - Tweaks - Repairs / Re: Blackstar Club 40 - Have you ever seem such a failure?

« Last post by tubeswell on September 06, 2025, 10:27:06 pm »

I may just buy another board if they are still available.  I see them for ~200.00

Is that for an empty board? This could get unreasonably costly - you might want to check back with the owner first.

2

Sound clips / Re: Platefire Instrumental "Walking the Walk"

« Last post by Platefire on September 06, 2025, 09:59:36 pm »

Thank you!! Yes come on by and we'll shooter

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Tube Amp Building - Tweaks - Repairs / Re: Troubleshooting a new build amp

« Last post by Williamblake on September 06, 2025, 04:38:23 pm »

V3 Pin1 is probably just a typo. Are your grids 0 V DC or did you not measure them?

4

Sound clips / Re: Platefire Instrumental "Walking the Walk"

« Last post by shooter on September 06, 2025, 02:48:14 pm »

nice pick'n!

If i ever get my flying camera out, I might come by and ask to steal that for overlaying some audio with the video

5

Sound clips / Platefire Instrumental "Walking the Walk"

« Last post by Platefire on September 06, 2025, 01:36:06 pm »

https://soundcloud.com/connie-and-bob-scott/walking-the-walk

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Tube Amp Building - Tweaks - Repairs / Re: Deluxe 5E3 tone stack

« Last post by Platefire on September 06, 2025, 12:40:36 pm »

Fun discussion! I find the tweed fender 5E3 and 5F2A tone stacks very interesting. They are so simple but can be very effective. On the old tweed amps just the raw signal sounds pretty good without anything added but are sometimes too dark, especially for humbuckers. So this tone stack can throw in just the right amount of sparkle into the mix as needed.

BTW--just a few simple changes, you could get your 5E3/5F2A tone stack back  

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Tube Amp Building - Tweaks - Repairs / Re: Blackstar Club 40 - Have you ever seem such a failure?

« Last post by jukelemon on September 06, 2025, 12:40:34 pm »

---might be a lot more to be found?

Yeah...I am afraid that may be the case and that's a lot of time and money to spend for the customer.


These are known to have bad boards all the time and I am weary to repair these caps and then find another issue.


I may just buy another board if they are still available.  I see them for ~200.00

8

Tube Amp Building - Tweaks - Repairs / Re: 5879 tube data sheet question

« Last post by DummyLoad on September 06, 2025, 12:31:01 pm »

I start with the cheat sheets. Nearly all audio pentodes have published data on bias parameters.

Resistance Coupled Amplifier chards provided in most tube reference. The attached an excerpt from the RCA Receiving Tubes Manual. Link to the rest charts below. V.G. colum is that what you seek.

RCA Charts here. 

9

Tube Amp Building - Tweaks - Repairs / Re: Blackstar Club 40 - Have you ever seem such a failure?

« Last post by Platefire on September 06, 2025, 12:25:04 pm »

Wow! Looks like pancakes on the grill! Well, you know where to start at---might be a lot more to be found?

10

Tube Amp Building - Tweaks - Repairs / Blackstar Club 40 - Have you ever seen such a failure?

« Last post by jukelemon on September 06, 2025, 11:59:22 am »

Hi all!


So this Blackstar Club 40 comes in. Power/Volume surging in and out.


Open it up and see 10 caps look to have exploded.

Getting high voltage when I probe the top of the power supply caps.

The "have you seen" question is this... I am ALSO picking up 250-400vdc when I probe that rust/brown residue.


It is as if the caps have bonded together on the top of the board?