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.
A 1967 YBA-1 is reported to feature a diode rectifier.
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.
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.
These mods are worth doing to any Signature/Bass-Master, IMO. CAD 3 used, bad price, amp in average (5/10) condition, Song Bird Music, Ottawa, Canada, summer 1998 US 5 [used], needed a little work but playable, cheap buy US 9.99 [used], seen at September 1998 CAD 9 [used], good condition, seen at Used Music, Ottawa, September 1998 CAD 0 [used], shabby condition, very early (pre October 1966) wrap-around type case model with tube rectifier, seen at Used Music, Ottawa, September 1998 CAD 5 [used], ca.
] 0 [used], very early model, the serial number is 0278, which places it in 1966, uses 6CA7 tubes as specified in the tube chart, no tube rectifier, and the marshall style phenolic turret board, also, it has the hole in the chassis for the tube rectifier socket, but it is blocked with a circular steel plate, the 5 volt rectifier heater winding at the power tranny is cut about 2 inches out, December 1998 Rating Very good one. I have a 1977 YBA1 with a matching YT-15 cabinet [...]. It's probably not worth a tird as a collector's item but this amp really screams. I rate my YRM-1 second to my YBA-1, because it does not have as much balls.
This must have been one of the last real Traynor amps made... Also, my YBA-1 sounds great at all volumes, including low setttings. 1965 or 1966 YBA-1 Bass-Master (old wrap-around style case), logo 1965 or 1966 YBA-1 Bass-Master (old wrap-around style case), front view, angle 1965 or 1966 YBA-1 Bass-Master (old wrap-around style case), front view 1965 or 1966 YBA-1 Bass-Master (old wrap-around style case), back view 1966 YBA-1 Bass-Master, chassis 1966 YBA-1 Bass-Master, wiring 1968 YBA-1 Bass-Master (serial number 2xxx), front view, angle 1968 YBA-1 Bass-Master (serial number 2xxx), front view 1968 YBA-1 Bass-Master (serial number 2xxx), logo YBA-1 Bass-Master, catalog page YBA-1 Bass-Master, catalog page YBA-1 Bass-Master, schematic 10/1966 YBA-1 Bass-Master, schematic 6/1971-1974 YBA-1 Bass-Master, schematic 5/1974 - Please note: This schematic has a serious error in it.
(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've used it regularily throughout the years, gigging throughout the Detroit area, and later in the E. A plate load of 6K8 would have essentially zero gain and probably lots of other problems.That part of the hand-drawn schematic from 6/1971-1974 is smudged and hard to read, but it's definitely 68K.The 2nd one I bought [...] was totally moded for guitar with extra pots on the back and stock EL34s. I [...] have [an YBA-1A Mark II amp] that goes with [the YT-15 cabinet] and it's all sounds great. i believe, though i am not sure, that these 1a's operate in class "a". Other than the old no ground power cord and serious shocks and buzz it sounded better than what i was using.i stuck a master volume on the back, jumped the channels, and cranked both channels to 7-8, plugged in my custom shop '61 reissue sg, and it kicks so much ass [through 4x12 25w greenbacks] its indescribable i bought both a 1971 yba-1 and a 1972(? [...] the yba-1a is currently beating the snot out of an old mesa 4x12 with 90 watters in it. this would make sense to me considering how very crushing it is and yet chimey. The only real problem was it seemed to be blowing fuses.