light bulb limiter VS wall

[rafe]

help me understand . I have been playing my newly recapped GA-40 for about an hour through a light bulb limiter with decent results good tone, amp is silent with tele and volume up when not played. it's obvious the volume is stifled a bit it'sloud enough that you need a mic to sing . I switched over to wall and turned it on (5V4) rec. slow start ....it was noticeably louder but started making odd noises, I shut it right down ....stifled pops??? I don't know how to describe them, but I think(Know) it can't be run this way ....What am I looking for ....I'm clueless Thanks.....

[Lectroid]

Can you describe the odd noises in more detail?  Loud/soft? Continuous/intermittent?  Static grating/softer hum?  Be as specific and as detailed as you can if you want people to be able to recognize your problem from your written description.   

It ran "okay" with the LBL?  How many watts bulb?  Any odd noises at all while using the LBL?   

[rafe]

Very hard to describe like pops under water ....Not real loud . I shut it down right away because  I just replaced the OPT which was arcing and popping and although the sound was a lot different, I am concerned it is the same issue. No noise at all with the LBL....as quiet as an amp can be, 25-watt bulb. starts bright (not fully lit) and dims down. I have a variac and can check voltages at a reduced input  60v's . I can turn on the amp with LBL, amp and tele volume full and leave it indefinitely with no noise. Seems like its the amperage that is doing this???

[pdf64]

A 25W bulb is fine for initial tests, especially with no valves fitted.
However with all valves in place it’ll be reducing the mains voltage significantly, especially when the amp is trying to put out power.
Surely with the amp running, the bulb was bright?
Now would have the time for 60W then 100W bulbs.
Whatever, perhaps a valve or 2 in the amp is bad.

[Willabe]

....as quiet as an amp can be, 25-watt bulb.

What pdf said and,

A 25w bulb will probably bring the voltage down much lower than when the amp is plugged into the wall. So the tubes will have much less/little stress on them compared to the full voltage they would normally see.

At normal voltage any flaws in the tube could now be relieved/heard.   

[rafe]

I tried to get a 100 watt bulb, all they had were 25 watt refrig.   bulbs in incandescent.

[acheld]

Halogen lamps also work.

[bmccowan]

"specialty" incandescent lamps are still being made and sold. Many are decorative, but "rough service" lamps are out there. Here's a 75W: https://www.bulbs.com/product/75A-RS-TF-SAFETY

[rafe]

I did manage to find a 60 watt and that helps. I found three bad connections on two sockets. Hey were noisy when chopsticked (Chopstuck?) Sounds better I'm gaining on it . I have to look I may have some NOS 6SJ7's, the 6v6's are good and the 6sn7 I already replaced (NOS) Slight ghost notes. still using the limiter for now.

[Willabe]

Once an amp passes the smoke test with a light bulb limiter, you don't need it anymore.

Plug straight into the wall outlet.

[rafe]

I'm too scared.    and it sounds good . I realized I had the same tubes in the Ga-50T and changed one out. Sounds better........ tomorrow .....I'll take off the training wheels ....and post a report..................But I'm really happy with this Les Paul this one has the origin footswitch sans switch and wire, rumor has it that these were manufactured from the guitar cutouts(Think LP bottom cut out) it's mahogany this thing hasn't sung in over 35 years that it was in the fiddlers nephews hands and there is no telling how long it sat around before that .The PO (nephew) told me he got the 2 amps when His uncle died. He never plugged them in and carried them about for over 35 years from house to house as He moved around..... and He (uncle) was a fiddle player  in a working Hillbilly band, that played all around N. Fl and Ga. when He was young. His Aunt told Him she believed He bought both amps new.   

[rake]

My local Ace hardware has 150w & 300w incandescent bulbs in stock.
Any Ace hardware should be able to get them or you can
order them at Ace.com and pick them up at your local store.
My limiter has a 300w bulb in it.

[bmccowan]

The PO (nephew) told me he got the 2 amps when His uncle died. He never plugged them in and carried them about for over 35 years from house to house as He moved around..... and He (uncle) was a fiddle player  in a working Hillbilly band, that played all around N. Fl and Ga. when He was young

When you find something with history like that - it's a treasure. That's mojo! I bought one of my old amps from the granddaughter of a lap and pedal steel player who had played in dance halls throughout the Smoky Mountain Region. I actually tried to talk her into keeping it in the family, but she was ready to let it go. I keep a sweet note from her inside the cabinet.

[acheld]

My limiter has a 300w bulb in it.

300W in the US (with 120VAC at the wall) delivers 2.5A --  too much for my builds which typically use 2A (or less) fuses.  A 100W bulb (halogen or old fashioned incandescent) will deliver 0.83A.

For most builds, a limiter is used once at initial fire-up, just to make sure there is not a (bonehead) short.  Once it passes this test, best practice is to move to standard wall voltage and current availability.

[rafe]

"When you find something with history like that - it's a treasure. "


It sure is. I kept his number and called Him today and played it over the phone for him. He was very happy with that. I told him i'd like to know more about his uncle and the history behind him amp and band . He said He is taking His mom out to dinner this week and He will find out ....I think this is awesome stuff

[Lectroid]

I'm too scared.    and it sounds good .

Willabe was right.  Plug that thing into the wall and don't look back...

[rafe]

"Willabe was right.  Plug that thing into the wall and don't look back..."


Lectroid, That was "Tongue in cheek" The next day I moved ahead it's an almost done deal. Going to have the speaker re-coned and might do a couple resistors. It had a few bugs in it that I chased down. It's really an incredible piece of Gibson history. AND one of my best sounding amps tone wise. It's a lot louder than I expected ....The next one is similar but with 6L6GA's instead of 6V6's. I am going to put it back in the cab and hook up a 1952 P12N in it until I get the P12Q original speaker redone. .....But I'll have to keep it low until I get the speaker back, right now I have it wired into the Celestion vintage 30 in my GA-19RVT....That can handle the GA-40 I'm not so sure about the P12N.

[Lectroid]

Good.  I'm envious of your amp.  I'm glad it came to someone able to appreciate it AND maintain it properly.

I keep trolling everywhere for an old vintage amp that somebody's uncle "used to play 40 years ago that's just been catching dust ever since, and why don't I give them $100 bucks and call it a deal?"

Yeah, afraid those days are gone but that's my dream...

[rafe]

Those days are fewer and further in-between but not over . These two were pricey, but undervalued (only because I can do a lot of the work) but because they were so close, I pulled the trigger on them. Don't give up, keep the faith it still happens , you just have to; ignore coincidence, be informed, prepared and lucky!

[bmccowan]

I keep trolling everywhere for an old vintage amp that somebody's uncle "used to play 40 years ago that's just been catching dust ever since, and why don't I give them $100 bucks and call it a deal?"
Yeah, afraid those days are gone but that's my dream...

Why not just pay a fair price, like Rafe did. Its a better dream.