Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: bmccowan on February 10, 2023, 05:56:01 pm
-
I just picked up a little Valco amp similar to a Vibro Champ.
Fixed a few things and it sounds very good.
The tremolo has a speed control but no intensity pot. For me it is too intense to be useful. I do not want to add a pot, but I'd like to find the right fixed level.
I've attached the Gretsch 6151 schematic which is identical.
I know how to slow the speed, but not how to reduce the effect.
Should I add a resistor to ground where the cathodes of V1 and V2 connect? or change the value of the resistor from V2b cathode (pin8) to ground? Or is it neither of these?
The only other changes I made were to change the bypass capacitor on V1 from 35 to 4.7uf and adding a 50uf bypass cap to the power tube + the usual safety stuff.
-
There are more than one way to lower the intensity. I'd try this first...
Lower the value of that 470K. A 500K pot would be mighty handy to determine the value that makes you happy.
-
Thanks Steve. I've got plenty of pots - so as you suggest, I'll experiment for the right level. I like tremolo, but feel like it should be a subtle effect - not "Crimson and Clover" :icon_biggrin:
-
Where is the pictures at? I thought when you made a new score, u post 2 sho eit aughf
I'm a big 1482 fan and always wanted an Airline 62-9013A. But just like the 1482 the pricesare out of sight. I understand that under the hood its got the same circuit as a 1482. I'm a Tremolo
guy also. Got 2 trem pedals and 5 amps with it
-
I like tremolo, but feel like it should be a subtle effect - not "Crimson and Clover" :icon_biggrin:
Crimson and Clover is subtle. Now this is intense...
-
Ha! Too Much to Dream Last Night brings back nightmares of 8th grade school dances, and Crimson & Clover brings back nightmares of dance nights at the Rangeley Inn - although the latter were usually followed by enjoyable late nights watching bears at the Rangeley Plantation dump. The band that played at the Rangeley Inn was actually named Crimson Tide and they would play Crimson & Clover at least 3 times each night. They did not know too many songs.
-
Sluckey - 120K worked pretty well - thanks again. I also changed the 100K input grid stopper on the "low" channel to a 33K. Perked it up a hair.
Platefire - I will post a couple photos later on. I hear you on amp prices. I lucked out on this one $115. It was listed as not tested, but the only failed part was the fuse holder. Had all RCA tubes which are in fine shape.
Finding an Airline 62-9013A (Dano) would be cool. I've seen them lately for $500. Too much?
I have two Dano Silvertones - an older 1433 that is waiting to be recapped and a newer 1432 that I did a while ago. Those Danos have lousy leaky Sangamo tone caps that are tucked into some damn tight spots.
-
This is a rare bird. I've never seen one in person. A 1473 bass amp. Looks like an oversized 1482.Was you aware of this one?
-
Nope - never seen that one.
One of the Silvertones I bought was in a non-ebay online auction. the auctioneer had bundled it with a lawn chair and a cheap plastic fan. He was surprised when I asked him to donate the chair and fan to a local charity and send me the amp. He had bundled the amp with those items so that he would not "get stuck" with it. :laugh:
I like this one https://rivingtonguitars.com/products/vintage-1950s-silvertone-model-1346-twin-12-combo-amp?variant=39449818890338 (https://rivingtonguitars.com/products/vintage-1950s-silvertone-model-1346-twin-12-combo-amp?variant=39449818890338) but not at that price.
-
WoW! That's a new one on me. I kinda like it! It has a volume for each channel, then what is the Amplification knob for(MV)? Thanks for sharing that info. I might try to look up the schematic on that, if it exist.
After I graduated high school in 65 I got rid of my 1482 and bought a Gretsch Variety 2-12. It had a bass and lead channel. Every picker in my little saw mill town wanted to borrow it and some did.
-
I think I have that amp or very similar Gretsch Valco - 2x6L6, 2x12, 2-channel, vibrato and reverb. I bought it dead and my expectations were low, so it sat in wait for a year or two. When I finally decided to bring it back, I was amazed. What a great sounding amp. I think its a 6165, but it does not say Variety on it.
That Kalamazoo brings back memories of my first band, 7th grade. My bandmate had that guitar, it was much nicer than my Silvertone Dan Electro, and he could play a lot better too.
Don't get shooter and I started on Kalamazoo.
-
:laugh:
sadly, companies like, Gibson, Shakespeare (think fishing), have been replaced by the world's largest drug dealers, Pfizer and Monsanto.
-
The Kalamazoo I always thought of as a Fender Mustang knock off, it was obvious---except not as good!
On the the Gretsch I have attached the sales brochure info on the 6165 Variety Plus(with reverb) and the 6164 Variety (No Reverb). So yeah, yours must be a 6165!!
I bought this amp so I could play bass in a band called the "ByGones" but I also played regular guitar apart from the band. The ByGone Lead player was a good friend that was a lot better than me, so I took the bass chore. The same day I bought the Gretsch amp, i bought a Framus Bass. A little later I bought a cheap self contained reverb unit so I could have reverb. I worked all the summer of 65 in a saw mill so I could buy this rig
-
Thanks - I think it is. Valco made every damn configuration they could think of. And for every outlet they could sign up: Supro, Gretsch, Wards-Airline, Ohahu, Vega, National, etc, etc, including some private labels for large music stores and schools.
I wonder where Framus got the idea for that headstock, eh? "Bygones" good name.
-
Sluckey - 120K worked pretty well - thanks again. I also changed the 100K input grid stopper on the "low" channel to a 33K. Perked it up a hair.
Platefire - I will post a couple photos later on. I hear you on amp prices. I lucked out on this one $115. It was listed as not tested, but the only failed part was the fuse holder. Had all RCA tubes which are in fine shape.
Finding an Airline 62-9013A (Dano) would be cool. I've seen them lately for $500. Too much?
I have two Dano Silvertones - an older 1433 that is waiting to be recapped and a newer 1432 that I did a while ago. Those Danos have lousy leaky Sangamo tone caps that are tucked into some damn tight spots.
And I found an Airline 62-9013A. About $300 and it came with a Fulltone OCD overdrive pedal, Voodoo Lab power supply, and an Old Blood Noise headphone amp. Its in solid shape - stock except filter caps and an Italian P12r. Sounds good, even with all the Sangamo caps in there. The filter cap replacement looks like a drunken silicone caulking tube job, so I will redo that, upping the values to 20-16-10 and test all the caps. Circuit is almost identical to the Silvertone 1472, but not quite. Inputs and heater circuit are different. The only 9013a schematics I've seen are very blurry, so I will draw it up and share. Before I do, @Platefire, did you ever draw up yours?
-
Boy! You've done it again and found another deal. You just paid for the extra stuff and the amp was free :dontknow:
Here is the Airline schematic. Don't know if it's any better than what you got. BTW --Great deal! Need to see some pictures now
-
Hi Platefire - thanks for posting the schematic - its the same as the best one I have for that amp. Can make out some of it.
You asked about pics here are 3. Gut shot is after I removed the klugey filter cap silicone glue blob. In the 3d pic you can see that it came with the optional Mud Wasp Turbo Echo Chamber.
I redrew the schematic, but will start a new thread as I have a couple of questions.