Dating srv stratocaster
437 volts); this may have gotten higher after 1971, but into the summer of 1971 I'd expect the plate voltages on 6CA7s to be down substantially from the YBA-1A; have the chassis sliding-in ala Fender.
Last versions have that easily identified rubber and 'chrome' molding running around each end of the head cabinet; mine is from 1971 and is this last version; 1972 models have no choke; [a 1978 is] black with the black plastic fabric and [has] the baby bumper trim, [it has] two 6CA7 and three 12AX7A tubes in it [and] no fuse holder, just a red reset button I put Mullard EL34s in my YBA-1.
One [channel] sounds kind of like a "bright" channel and one sounds regular Two 6CA7/EL34 power tubes, three or four 12ax7s, solid state rectifier; hand wired, very high quality work, simple easy-to-modify circuit; larger [than the ones used in the Bass-Master YBA-1] 50-watt Hammond transformer (7 lbs.); Often operated with 4 ohm loads; best used with an eight ohms cab Runs on 540 volts, weights 54 pounds - bigger transformers [than the YBA-1] Dimensions: 8"x18"x10" (HWD); weight: 40 lbs.? (source: Catalog) Early [Bass-Master] Mark IIs have the (noisy) fan mounted on the end [in the cabinet side], later [Bass-Master] Mark IIs (with lift-off top, and the reflector 'Traynor' logo) have it mounted in the back [center]; Silvery grey grille cloth; Can exceed 600 volts on plate; expect about 550 volts, if you're lucky (one has eported 537 volts on plate) Early models are identical in appearance to the Voice Master/Signature.
I have swapped out the 4M volume pots for 1M, and put a 47K resistor in the NFB loop.
] 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.
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.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.[Oct 2002] US 0 used; one can be bought for under [US] 0 - a total bargain US 0 [used], needed a little work but playable, cheap buy US 9 used, you can get one cheaper CAD 0 [used], good condition, seen at Songbird Music, Ottawa, November 1998 (since January 1999 though, it had changed its condition to 'very good') Rating very good amp My personal opinion is that the YBA-1 is better for guitar, while the YBA-1A is preferable for bass.
My YBA-1A [...] uses 6550s and it's the best rock bass head that I've owned.[...] When [the YBA-1] ran on 7027s, it was a rock machine (think Black Crows, Zep, etc.).It probably has a bit less bottom end and more mids and highs now. It must have been one of the last YBA-1 Traynors made.They feature a 'flip-top' design that allowes the top of the head to open like a lid.