Yamaha B100 Head

The serial number on my Yammy is 4xxx, made in the 70s
I generally play rock and punk, so i like my sound to be dirty or grungy. The B100 is an awesome solid state head. I got it failry cheap aswell. It is pretty straight forward as already described. The only problem with this head is when you turn on the distortion, it cuts out a little volume and some lower frequencies. But i have to say i love the sound of this so called "cheap" sounding distortion, its actually quite unique. I also noticed when it is turned on, it is actually running a clean signal as well as the distorted signal. I've never seen anything like this until i played around with this head. Ive had it about 8 months now and it hasnt let me down yet. Plenty of volume for gigs.

I generally use my ErnieBall Stingray 5. I love the grunge i can get with this head and my bass. You can easily play clean as well, as long as the volume isn't turned up passed about 5. When you start to push it, it gets dirtier, and thats where i use it. The birghtness knob lets you play with the tone alot. I love how this amp sounds.

Ok. Here's the best part. 30 years, still working great, it has lost the rear pannel and the fan. Doesn't effect it one bit, ive used it for hours on end without it overheating or cutting out. At one of my recent gigs, i let my friend's band use it after my set and their guitarist tripped over a bunch of patch-chords and he actually brought my 810 down. My head was fine, still works, you'd never even know it fell 5 feet to the ground. ha

Overall, this head is amazing, especially for the price.

The amp is a 70's era 100 watt bass head. I alternate between some jazz groups and a metal band, and it handles both well. It is LOUD. I use a peavey b-quad bass with active pickups and my guitarist starts grimacing if I go above 3 on the volume. The day I got it I went up to 4, and the door of the toaster oven in the kitchen UPSTAIRS fell off and shattered on the floor.
The head as Low, Mid, and Hi eqs that work well and do not need to be turned drastically to kick in. I have my bass at 6, Mid at 5 and Hi at 4. The front also has controls for the built in distortion, one knob for "bright" and the other for the amount of distortion.
The back has 2 outputs, a rec out, a distortion pedal jack, and (very nice) a three prong outlet. The head is only one channel, but it has a hi and lo input. The high is nice for a great bassy guitar amp.
The distortion is kind of worthless. It sounds pretty bad, like a 1-bit filter. I actually would use it just for that reason if it didn't cut the volume significantly. Like half. Otherwise it'd be pretty cool.
I would like to get the guitar version, the G100, sometime and run my highs into it. I hear it has a great tremelo effect.

I use a peavey b-quad with active pickups. (and a piezo pickup) The amp sounds great with any setting I throw at it. It handles intense lows (for one group I play in drop d) and never breaks or cackles. The knobs themselves are noisy when they move, but that doesn't effect the sound while you're playing. Having a High and low input is great for using either guitar or bass, and the eq knobs are very versatile.
Like I said before, the distortion sucks. the controls for it don't help much. Again, if it didn't make the sound quieter, it wouldn't be bad, but there's no use for it unless you play super loud and then have regular quieter sounding distortion.

I've had the amp for a year, it's obviously been around 30 some years and it's still kicking. I assume it's pretty reliable, and if it ever broke, I'm sure I could fix it. I use it without backup all the time.

No idea about getting it repaired - I assume I'd do it myself. I got it from a pawn shop so... yeah.

This amp came with a very large Yamaha 2x15 cabinet. The cabinet looks like it matches the head, but I've never seen anything like it on ebay, harmony central, or anywhere else for that matter. The speakers are shifted to the right side, and on the left side there's a gigantic vertical ported duct. Halfway up the duct there's a piece of wood like a shelf for support. Anyway, I don't know what it's deal is, but it's great. I run the amp into that and also into a peavey 2x10 plus 2x12 tower. The sound is huge. I paid 275 for the head and the 2x15 cab, so I just put 100 bucks for price paid cause I dont know.
I know it's only 100 watts and they have amps up to over a 1000, but I seriously cannot imagine a louder amp. Maybe with a passive pickup bass you'd need one for a large venue, but for me this thing is insane. If it ever accidently got up to 5, i'd probably lose my hearing.
If it were stolen, I'd go on a great pawn shop hunt and find another one. Like the other guy that reviewed it, I really want to get the g100 and use that too. They look cool to boot.

sounds pretty good, use 4 x 10 inch laney 320 watts and a 15 inch 350 watts.
I put the volume on 5 or 6 and it sounds great!

Never let me down for over a year now!

its good for me

pretty straight forward head with distortion. high and low input, 2 speaker outs and a very handy jack in the back for plugging in pedals or what have you. it has a very retro sound to it think early alice cooper and cream. no matter what its always a little dirty even with the distortion down. from what i can make out on the back panel my amp was made in 1979. i generally set the volume about 6 or 7 and the distortion at about 5 , and get a very cool sound out of it. if your looking for massive clean headroom look elsware. i play in a band with 2 guitar players and a keyboard player and this thing cuts through very well. i use an early crate 410 cab with swr speakers in it.

my main two basses are a yamaha attitude(billy sheehan model) and a american standard ash body jazz bass. they both sound great through it the fender just a bit better notes ring alot clearer. i play pretty wide range of music 60's to present, also alot of blues. no noise at all. very nice and quite suitable for recording. even cranked the distortion is not over the top when i got this thing i sold all my pedals this thing does it all for me. if your into that vintage sound youll like this amp if you like victor wooten and steve bailey you wont.

ive had for a year but it gets used all the time. i would definetly use it without a backup. hasent let me down yet. the early yamaha stuff made in japan is very well made.

ive never had to deal with yamaha. since this was made in the 70's i dont think they would be much help.

i love this thing, i have since bought another one and the g100 guitar version. there great but i think there an aquired taste. another one of my bass playing buddies hates it because you cant really get a super clean tone. when i got this he bought my swr350 bass head wich is a great head but ill keep my yamahas. if it were stolen i would probably have to kill someone, thats why i got another one. if you get a chance to play through one of these i would definetly give it a chance. rated at 100 watts but just as loud if not louder than my swr wich was rated at 350 watts.