Got an amp. Demo Beatles cover page 5

[Fiddy]

^Thanks boss! So happy with it

[Fiddy]

Damn, I just spent $145 on caps. Soo expensive these days...

[OffYourFace]

from where?

[JSett]

Damn, I just spent $145 on caps. Soo expensive these days...

Damn, the Canadian dollar is that bad? I don't think I've ever spent more than about £50 / $85CAD on a full set for a vintage amp! And I only use the primo F&T too!

[Fiddy]

I got all F&T, except for one Sprague. ..but yeah, pricey. Amp repairs gotta be probably super expensive these days. Amp techs gotta eat too.

[øøøøøøø]

Inflation is hitting everything.

The last few times I’ve placed orders from Mouser the total after shipping has been considerably more than I expected; it’s just a fact of life, sadly

I’d imagine the comparably minuscule demand for things like axial lead electrolytic caps doesn’t help

[JSett]

I got all F&T, except for one Sprague. ..but yeah, pricey. Amp repairs gotta be probably super expensive these days. Amp techs gotta eat too.

Damn. It's been about a year since I did a recap on anything so maybe Im out of the loop.

F&T and Sprague (for the sizes F&T don't make) are my go-to. Good job they only need doing every 20 years!

[Fiddy]

from where?

Sorry, I missed this. I got them from The Tube Store. They're about a 15 minute drive from where i work. Unfortunately ,it is the opposite way and I work about 65 KM away, so im getting them shipped instead.

Im very excited for this amp can't wait to enjoy it once done. Is your bassman circuit close to this one?

[OffYourFace]

from where?

Sorry, I missed this. I got them from The Tube Store. They're about a 15 minute drive from where i work. Unfortunately ,it is the opposite way and I work about 65 KM away, so im getting them shipped instead.

Im very excited for this amp can't wait to enjoy it once done. Is your bassman circuit close to this one?

We look forward to hearing about it when it's done!
Your amp is closer to a Marshall where the tone stack is on the 2nd gain stage.

My Bassman was an AB165 and I changed it to the AA864 specs. It was a ton of work but worth it. I basically had to rewire the whole board. If you look at the schematic for the AA864, I just did a few tweaks to the Bass channel.

First, I ditched the 'Deep' ckt. (removed the .1 cap for it) and I rewired the switch to work as a midrange 'shifter'. It switches from the stock 2.7k resistor to the 6.8k resistor that's used in most Fender guitar voiced amps. It's sort of like turning your midrange knob from 3 to 6. It's not a drastic change but can enhance the sound depending on what kind of guitar you're playing. Second, I changed the tone stack to use two .022uF caps and a 56k slope resistor. I find it to be a more 'focused' arrangement. Last, I added a 56p bright cap just to give it a little sparkle. The result is still a Blackface Fender sound but with a little quicker attack/transients like a British amp.

The normal Channel is basically a Bandmaster now but with a beefier Bassman OT. I added a .1uF coupler before the PI just like the Bandmaster. The effect is very subtle, just a hair more focus in the mids. It was a butchered amp so it was ok to change it. Anyway, sorry for the hijack but that's what I did.

[JSett]

I toyed with changing my AB165 to the AA864 circuit but, to my ears, it sounds exactly how I want it to so didn't bother.

From what I've played of these old YBA amps they definitely sit well in that early Marshall/Bassman territory and sound fabulous at around 6 or 7 on the volume dial. Strum a big open chord and they do that thing that we all want of it blooming into a great classic overdrive sound. Think "opening chords of The Boys Are Back In Town" (probably the best rock pop song written).

There's an early 70s YBA-2 near me for sale that I've been super tempted to pick up. I've held back though - but this thread is not helping.

[Dr Tony Balls]

Is your bassman circuit close to this one?

Clarifying with my knowledge here. The answer is emphatically no.

The circuit in your amp is much more akin to the 5F6A Bassman (aka the TWEED one from the 50s) which shares very little in common with the Blonde, Black and Silver-faced Bassmans that came after it. Little enough that other than the name, i'd consider them unrelated. The 5F6A Tweed Bassman, however, was liberally borrowed from (copied) by Jim Marshall and about a zillion people after him. Your amp has MUCH more in common with a Marshall plexi than anything Fender made that wasnt wrapped in tweed.

[Fiddy]

Right on. Thanks for the info.

So, there are no crackles, pots are smooth but i did spray electronics cleaner prior to powering it on.

Also, visually the filter caps don't show any damage, no bulging and shit... There is some hum, that being said, Ive owned new production amps that are just as noisy as this one is.

I think it's safe to play until the new caps arrive.

[Dr Tony Balls]

There is some hum,

What frequency? Use can use many a cell phone tuner app to figure out if its 60Hz or 120Hz and that helps to narrow down the source.

[Fiddy]

Thanks for the tip. I'll check tomorrow .

[Fiddy]

I guess it is 60Hz .

I replaced the burned and suspect resistors. Doesn't look pretty but it's functional and safer than before.

New caps tomorrow. This amp sounds so good. Great bass and sparkle at the same time. Even with humbuckers.

Handles the Firebird like a true champ too.