Is this a Tube Amp???

Discussion in 'Amps and Cabs [BG]' started by CreatioN, Nov 26, 2003.

  1. Hey,

    I'm thinking of buying this Amp Top. I already played it and all. But I don't know if it is a tube or transistor amp. It's not listed on the amp.

    It is heavey and when you turn it on, it takes a few seconds to make sound. It also has a large front side with a thin fabric thru wich air can flow. Don't remember any fans and standby button though. The seller didn't know either.

    It's a Yamaha b100II 250 Watts Head. It comes with a 15" speaker (150 Watts) from a different brand (pentatonic). It isn't expensive en looks really good so I think I'm going to buy it.

    EDIT: I don't seem to be able to post a pic, but you can find it here:

    Hope this works.

    Anybody know this Yamaha Amp? Is it a tube or transistor? NE body know Pentatonic? Never heard of the brand, but the speaker sounds pretty good.

    I couldn't find anything on the i-net about these things so I'll hoping you can help me out a bit.

  2. If you check the back of the amp and see big bottles and little bottles glowing. Then its a tube amp. If u see nothing glowing. then its most likely a solid state amp.

    An all tube amp mostly likely looks like this from behind.
  3. I think I've used that amp in its combo form at a gig, borrowing it from the other bassist. Not a bad sounding amp at all if its the one I think it is.

    I would think it's s/s, but I can't say that I checked when I used it.
  4. Chasarms

    Chasarms Casual Observer

    May 24, 2001
    Bettendorf, IA USA
    That amp is SS in both the preamp and output stage.

    I had a friend who had one of those MANY moons ago. It sounded OK. I think you may be being a little optimistic to think it can do 250 Watts RMS. Maybe it does at 4 ohms, I don't recall for sure.

    It was decent sounding head as I recall.

    As for the cab, I have never even heard of the maker, but if it sounds fairly clean I wouldn't worry about it.

    I probably wouldn't pay more than $250 or so for the whole thing. $300 at the most.
  5. S/S = Solid State...?

    Then why is it so heavey?? And why the big front?

    And don't worry, I'm not paying more than 200 Euro for it...
  6. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    That's a 100 watt head, it's 100% solid state.

    250 watts is the power DRAW not the OUTPUT. All amps draw more from the wall outlet than they drive into your speakers(the rest turns into heat...that's why amps get hot!). Solid state amps usually draw about 2x the output power, tube amps usually about 4x the output power.

    In the USA it's worth $200 tops, I see them often for $100-150. They sound OK but not fantastic.

    It's big and heavy because it's 70s technology...big power transformer.
  7. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    Those head are SS through and through and 100W at 4ohms (hence the B100 designation). It needs an efficient cab to be of any use for a gigging situation like any 100w head.

    It is a great sounding head for what it is, compares well to a V4B IMO.

    It is heavy becasue of the ridiculously overbuilt cabinet and very generous transformers that were used.

    200 Euros is a good deal if the cab is included.
  8. Actually, unless they are single ended, most tube amps draw the same as ss amps, usually under 2.5 times the output wattage after accounting for filament current.
  9. Hmm.. So its a Solid State 100 Watt amp... Bummer. It sounds good, but I guess I can get something better for that, or a little more money. I've seen a Peavey TNT 160 (160 Watt) for 250 Euro. Only thing is that I was looking for easier to move around amps.... Those combo's are a bit too big.

    The cab that came with the Yamaha is just a 15" speaker crammed in a small box, nothing special, sounds good but I would need better speakers for gigging. And I would need more than 100 Watts for gigs...Too bad.

    I guess I'm going to think about it for a while, don't want to make any wrong decisions.

  10. Scott D

    Scott D

    Apr 21, 2003
    Minneapolis, MN
    I used to have the older version of that amp, it sounded pretty awesome. Yeah, it's solid state, but sounded good. The only reason why i sold it is because i had a nice ampeg and i didn't need it at that time.
  11. The 160 watts vs 100 watts isn't really going to a big enough issue to spend an extra $50 on I wouldn't think.

    Is the TNT the 1x15 as well?
  12. Yeah, it has a 15" speaker. Haven't played it or anything yet. But it looks nice, It has a compressor, chorus, 9-bands EQ.

    Much more options than the Yamaha, and newer (1994)

    Only bad thing is its size and weight. The Yamaha set is much smaller than the Peavey.

    I keep getting second thoughts about this stuff. I'm going crazy. Don't really know what to do. I still would like the Yamaha, but for less money. Would 100 Watts be enough for a church band? With a loud drummer and guitar. I don't play on the PA so the amp needs to make enough sound for the whole room...

    Choices, choices, choices.... I had a 100 Watt H&H combo but it sounded very dusty and uncontrolable at high volumes...So I sold it. I don't want anything like that again.
  13. nonsqtr

    nonsqtr The emperor has no clothes!

    Aug 29, 2003
    Burbank CA USA
    Yeah, a hundred watts is right on the hairy edge of being usable. I would target a slightly higher power range. IME about 160 watts is the minimum to compete with my drummer and get the sound out into the audience. Depends on your sound too, you can get away with slightly more or less power if your sound is fat or clean.
  14. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    The only way I could see getting the B100 to work in that situation is if you got a greater number of speakers to work with. For example an 810 (or 2 410's) will go much further than 115.
  15. I take it there's no way to do a side by side comparison of these two options? I mean it would be good to see how well they each perform at high volumes, and if one is actually noticeably louder than the other.

    I've played 350 watt amps that were no louder than a 200 watt amp by another maker... just something to take into consideration.

    And yes, more speakers would be the most help for more volume rather than more wattage.
  16. Guys, remember...adding more speakers will mean less excursion for the multiple cones being fed by that underpowered amp...translating into the poor old relic trying in vain to move more air but only succeeding in heating up the voice coils in the multiple speakers. You're gonna fry speakers or the amp. My bet would be speakers. (Y'all do understand the principle of why we desire and shoot for as much headroom as possible in an amplifier, don't you?) I'd let the old boy rest in peace, but if you've got to use it...let it feed what it was designed for back in the 70's: a decent, efficient 4ohm 15" speaker.
  17. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    That makes no sense at all!

  18. So.... More speakers can move more air, but if they are connected to a small Amp, the amp won't have enough power to make the speakers move more, so they wont move more air. Hmm.. Whatever.

    I saw an old Kustom head (200 Watts) for very little money so I'll check that out. I'm just going to keep all options open and keep looking around for a while until I find something really usefull.


  19. rumblethump

    rumblethump Supporting Member

    Mar 25, 2000
    Pioneer CA. 95666
    If the old Kustom is a Kustom 200, then it also a 100 watt amp. :mad: Not a bad sounding solid state amp though.
  20. Its a K III lead top. I found out that its an 130 Watts head. Comes without a speaker. Missing 1 treble knob en pots are a little bit cracky. Here are the specs I found on a website:

    The III Lead was Kustom's standard serious Rock and Roll amp for weekend Rockers.
    It features 130 watts and two dual input channels with the following controls:
    Channel 1 has Drive, Volume, Bass, Middle, Treble, Bright, Tremolo, Speed ,Depth and Reverb.
    Channel 2 has Volume, Bass, Middle, Treble and Bright.

    It's 135 Euro, that's around 130 Dollar. Good deal? Any experience with this amp? Or should I make a new thread? Can it be used as a bass amp? I also have a (bad) Pic:


    Take it or run away from it??