Dating srv stratocaster
A YBA-1 has a nominal 8 ohm output, and the two speaker jacks are wired in parallel.Runs on less than 440 volts, weighs 39 pounds Dimensions: 8"x18"x10" (HWD); weight: 40 lbs. (source: Catalog) Silvery grey grille cloth; Original layout was very close to the tweed Bassman and the Marshall JTM-45 50-watt models; noticably huge big heavy transformers are a Traynor hallmark in these units up till the approximately 1972 models; Early models were tube rectified (5AR4) and used two 7027A power tubes.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.I have swapped out the 4M volume pots for 1M, and put a 47K resistor in the NFB loop. Professional repairman required, although schematic is included, weird defects possible. The YBA-1 serial number is 8011108 the YT-15 serial number is 7125596.
The used tubes are, as indicated in the amp: Two 6CA7s (replaceable by EL34s) and three 12AX7As (also called 7025s or ECC83s); plate voltages have always been a question on these units, but I think this may be largely because of confusion with the YBA-1A models that run VERY high plate voltages; most of the YBA-1 models probably come in somewhere /-450 volts (one has reported 425 volts on plate, another one ca.) loud as hell class A circuit so there is little distortion, sounds very punchy and clear very mechanical sounding; SRV and Hendrix heads need not apply.If you are looking for something original sounding and with a good bit of style, this is it (if you can find one)!I caraked open the top on my 1975 YBA-1 just to look, and sure enough it's a 68K.(Dave, Nov 11, 2014) - corrected version (Brian, Craig, Dan Lear, Dave Rutherford, DCloud1050, Eric Knudsen, Glen H., Greg, Jay Rogers, Jonathan Krogh, joth, Kraig Olmstead, Moon Keith, Ron Waters, Tim Casey, Tony Flagg, Vernon Fitch, viva Analog at bc.ca/~jc) Features Two channels (bass and guitar), two inputs for each channel, upper inputs are slightly attenuated; Treble and bass controls, a "tone expander" section with low and high knobs (according to Dan Torres, these are actually midrange and presence controls); there are two volume knobs that can be blended to get different sounds.
Features silvery grey grille cloth Yorkville [...] owns Dyna-Bass #0011 and [has] used it as a promotional tool.