These mods are worth doing to any Signature/Bass-Master, IMO.
Sound Just like a plexi 50 watt Marshall (when used for guitar); Punk or loud rock (or with channel bridging Entwistle's bass sound) (when used for bass) Better sound as a Fender Bassman (bass and guitar); lower powered, would work just fine in a blues or lower volume setting (?
More power and punch than Fender, less ruggedness than Marshall.
I'd say its closer to a Vox type sound, but if you want Vox sound, this will not suffice.
typically playing a new gibson les paul "faded" through them. Even after a friend helped me switch the power supply to todays standards and no buzz and shocks occured. I am told it may need some work on the tubes (cost about same as amp itself). 1971 YBA-1A Bass-Master Mark II (top not removable despite later style case), front view, angle 1971 YBA-1A Bass-Master Mark II (top not removable despite later style case), front view 1971 YBA-1A Bass-Master Mark II (top not removable despite later style case), back view YBA-1A Bass-Master Mark II, catalog page YBA-1A Bass-Master Mark II, schematic 1/1969-12/1970 YBA-1A Bass-Master Mark II, schematic 1/1969-12/1970 YBA-1A Bass-Master Mark II, catalog pages, manual, fan conversion, schematic 1/1966, schematic 1/1969-1/1972, schematic 1972-2/1973 YBA-1A Bass-Master Mark II: Looks to be the same as the other one with a choke except it shows 6CA7 as the power tube instead of 7027 (Larry).
(Aaron, Craig, Dan Kukkonen, Dan Lear, Eric Knudsen, Greg, Jay Rogers, John, Jon Aley, Kraig Olmstead, Laws from Lawsstudio Canada, Moon Keith, Tim Baier, viva Analog at bc.ca/~jc, Features volume and tone controls only; it has two inputs, seems to be high and low, no major difference Two 6V6 power tubes This one is a '67 [amp] and is in amazing shape. ) speaker that looks identical to the 15" Jenson in my '64 Fender Vibroverb.
My personal opinion is that the YBA-1 is better for guitar, while the YBA-1A is preferable for bass. [...] typically playing a new gibson les paul "faded" through them. I got it brand new back in the late 1960s (I traded a dealer my Fender Super reverb even for it). It can be heard on all my recordings, and you can [see] me using it in the videos of my band, Terrain. Specifically, R36 needs to be 68K, not 6K8 as written.Sound It's got the best tone, but it's not the loudest (when used for bass). Both the YBA-1 and YSR-1 each have 4 input jacks, so I can jumper the channels and use both the bright and normal volumes to adjust my tone. 1966 early model, cosmetically it's in pretty good shape, the tolex is perfect, the grill has two tiny snags over at one end, but it seems this amp may have fallen face first at some time, when i got it there were only two of the 'chicken head' knobs, and the front panel screw holes were stripped, so you could just pull it off; there's no dents or anything in the faceplate, not even a scratch, internally it's perfectly clean, no dust or gunk anywhere, recently, [October 1998] CAD 0 used, together with a mathing used 4x12 cab, bought at a pawn shop, October 1998 CAD 0 [used], seen at Used Music, Ottawa, November 1998 [US?