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Bugera BTX3600 "The Nuke" Mysteries Revealed (Lots of Pics)

Discussion in 'Amps and Cabs [BG]' started by MuthaFunk, Jan 20, 2013.

  1. Amazon had these Bugera BTX3600's on for a hair over $200 with free shipping. For a price like that, I had to bite just to find out what the real deal is with this amp. Bugera claims 3,800 W Peak output power, absent distortion figures of course. That still seems rather outrageous given this amp is a typical class AB design. Typically to get RMS from peak values one would multiply by 0.707. That would place "The Nuke" at an output power of 2,687 W RMS. A North American home receptacle is typically limited to 120V and 15A which will supply a maximum of 1,800 WR RMS continuous power without tripping the house breaker. Despite these curious #'s, this amp seems to provide a lot of bang for the buck. I wasn't sure as to what kind of build quality I would find upon receiving this amp. Here's what I found so far...

    First off, this thing is heavy!! It feels like a formidable piece of equipment when lifted. The rack handles are a god send for an amp that weighs almost 50 lbs.


    The exterior looks rather nice. The knobs all feel solid like a high quality piece of equipment. The EQ sliders on the other hand feel a little loose and cheap when handled.



    The advertised power output, the built in 18A breaker, and the standard 15A IEC plug all add up to some fishy construction and/or marketing.



    This draws some concern if the amp really will put out and consume the kind of power it's advertised it does. If one were to somehow rig up a cable that had an IEC connector on one end and a 20A home receptacle on the other, and connect it to a 20A receptacle, it's possible this amp could run over the IEC plugs rating and heat up without the breaker tripping to protect the amp from burn up. To compound this issue, the supplied connecting power cord that Bugera sends with the amp is made of 18 AWG. I had a good laugh when I saw this.


    Although an 18 AWG could possibly carry an 18A load for a short while, here in Canada it's typically rated for 10A. I began to suspect this amp may not actually put out the same power as the advertisements.:rolleyes:

    Any time I purchase items made in China for a ridiculous low price I inspect the insides before I plug it in. This amp was no exception. I could hear "things" clanking and rolling around inside my unit when I removed it from the box. The interior doesn't look too bad IMO:



    The power transformer was much bigger than I had anticipated! I was pleased to see it. Still, there was no power rating on the transformer to indicate what this amp may be able to do. Perhaps this amp is capable of putting out some real big power after all.


    I immediately found the cause of the clanking. What could these be from??? They look like they're made of ceramic.




    Yep, that's where they go!


    The retaining clip for the transformer must have been tightened down to hard at the factory as the transformer was still very secure despite some of the pieces cracking off.

    Some of the wire routing inside was a little jumbled but overall there was nothing to be worried about. There appears to be 8 output transistors per side connected to each heatsink:



    The power caps are of a decent size to supply serious power as well but their 63V rating has me questioning the power specs again. From what I've seen, high powered amps typically have much higher DC rail voltages than 63V.


    The wires off of the IEC connector go right to the 18A breaker and off to the power switch. They are sized appropriately for the 15 A IEC plug at 14 AWG.


    This looks a little sloppy to me but as far as my pre-inspection goes, I couldn't find anything that would cause problems.


    The Speakon connectors appear to be connected with heavy gauge wire as well allbeit through a circuit board...


    There were a few less than perfect soldier connections on what appears to be the bridge rectifier power supply board.


    Other than passing the preamp signals over to each channel, I can't say what these connecting wires are for but I'm not too keen on the way they run over the heatsink. If this amp is going to put out any real power with these moderate sized heatsinks, they are going to get real hot, and running any wires directly over them is a bad idea.



    I could still hear "tinking" when I manipulated the amp around during this inspection. It took me while to track it down but I figured it out that it was the two heat sinks making contact with each other as the base flexed and the whole boards moved allowing the heat sinks to collide. This is not a good sign of durability. If the heat sinks are mounted to the circuit boards and the components are shifting enough to allow the heat sinks to collide the reliability of this amp may not be the greatest for rough road touring. It looks like there is some holes drilled and tapped where one could install braces to keep the heat sinks secured. Perhaps Bugera typically does this but mine did not get them. I can't say for sure.


    There was one more thing that kind of bothered me about the heat sinks. The fan expels air out the back and draws from either side of the chassis just behind the rack ears.


    The only problem I have with this design is they put a pre-amp shield right up against the heat sink intakes covering up the lower half of the heat sink. IMO this will only allow minimal air flow to the lower half of the heat sink greatly diminishing the efficiency of the heat removal from the output transistors. It looks like there was plenty of room to shorten the pre-amp shield stand offs and create ample flow to the bottom half of the heat sink but they didn't do that. IMO the design engineer should be questioned on what they were thinking?



    Here's some more pics of the pre-amp circuit boards...



    IMO much of this construction was a disappointment. For the price I paid I guess it was expected actually but they aren't always $200. Street price is typically $500-$600 for one of these. If I was a musician who was not keen on opening up my new amp to give it a once over or even do a few minor upgrades to improve reliability I would not recommend a Bugera amp.

    Despite my disappointment in some of the construction, when it was time to plug it in and give er a go, the NUKE actually sounded pretty good. I ran my Eden WTDI into the amp in and compared it to the Bugera pre. To my surprise, they sounded very similar. The Bugera pre-amp has so much tone shaping I was able to dial in a bunch of usable tones that could spread across a number of music genres.

    I also liked the compressor. You can use the gain to set the threshold and the compressor knob adjusts the ratio, a nice touch! There was no audible artifacts when the compressor kicked in until only the highest ratios were set.

    The graphic EQ has great Q widths allowing very smooth tone shaping to be done along with a EQ master level slider to allow you to boost or cut your whole EQ sound with the kick of a switch. Did I mention it came with a nice steel housed foot switch that will trigger the EQ and FX loop?



    The foot switch has a permanent 20' long stereo 1/4" cable attached. I personally prefer the Fender system but at this price point this is truly a gift from Bugera.

    I ran it in bi-amped mode, the frequency selector and balance knobs worked great, very easy.

    I even tried it as just a basic power amp from my computer sound cards outputs to run my P.A. Speakers and it thundered through the house. I have to say, I'm quite happy overall with this amp. I plan on using it for one of my "loud" gigs where I don't have P.A. support for the bass. I only do that gig once a month so it may be a while before I report back on that. I'm going to try it bridged into my Bergantino AE410 on that day.

    In the mean time, I still wish to answer what this amp will really put out power wise. I have all the equipment to perform this test and will report back in a short while with the results. Stay tuned...
  2. Johnny Crab

    Johnny Crab ACME,QSC,Fame/Hondo/Greco user & BOSE Abuser Gold Supporting Member

    Feb 11, 2004
    South Texas
    THANKS so much for opening 'er up for the photo shoot.
  3. arai

    arai Banned

    Jul 16, 2007
    Cool thread. Subscribed
  4. murphy


    May 5, 2004
    Toronto, Canada
    Thank you so much for all your photos and documentation.
    looking forward to more
  5. gumtown


    May 7, 2007
    New Zealand
    Thanks for sharing, interested to see the output power measured.
    Is it a clasic AB type amp, or their special digital switching types (as in Behringer)?
    (noted by the lower than expected power supply cap rating)
  6. Arjank


    Oct 9, 2007
    Above Amsterdam
    Great info!
    I have to say that my bvp5500 looks more clean and tidy inside...
    Seems there is no part nr on these transistors, else we could do an estimate on it's powerrating.
    I still think you can be happy if it can deliver 1000watts rms.
  7. Arjank


    Oct 9, 2007
    Above Amsterdam
    Here are the guts from my BVP5500 :bassist:
  8. Arjank


    Oct 9, 2007
    Above Amsterdam
    We have 230v 16A over here :D
  9. Excellent job! I suspect the heatsink brace was omitted to reduce stress on the output device's leads if there is that much flex in board/chassis? I would have had to clean up the bridge rectifier solder joints, maybe hand solder is not a strong point at the factory.
    looking forward to the tests that fallow.
  10. murphy


    May 5, 2004
    Toronto, Canada
    now that looks nice
  11. Sub'd. Having nothing to do with this amp, my experience with Behringer varies widely. The BDI di box/preamp sounds really good, very durable. The old aluminium cone single 15" in a cabinet was pretty bad. It was rated at 800 watts (haha). I blew it out with a 400 watt amp and I never had the volume past 4.
  12. seamonkey


    Aug 6, 2004
    Great information and camera work.
  13. Mehve


    Jun 2, 2012
    Kitchener, ON
    Heh, definitely going to keep an eye on this thread. Appreciate the effort.

    There's an online manual for this unit, and it lists a peak power consumption of 3600W, so I guess class D amps can eat this thing's dust for efficiency too.:rolleyes:
  14. Will Kelly

    Will Kelly

    Mar 3, 2010
    great job on the review!
  15. I finally got to hook The NUKE up to to power measurement equipment today.... I wasn't sure what to expect because when I got to turn the power up on the BTX3600 into my 5.3 ohm 610 the small rope lights I had plugged into the same circuit were really dimming with each hammer of my hand. It told me this thing was really pulling some serious current!

    Here's the work bench:


    My power resisters are rated for 300 W RMS each. First I ran each side of BTX3600 into 2 ohms independently because I just don't have enough resisters to get both sides down to 2 ohms at the same time. So, as far as running stereo, the best I could do is run both sides at 4 ohms. The third and final test I ran was bridged full power into 4 ohms.

    Using a 1 Khz signal in, and a maximum of 2% distortion here's the results:

    2 Ohm operation with only 1 channel = 930 WRMS
    4 Ohm operation both sides at the same time = 625 WRMS per ch.
    4 Ohm bridged = 1500 WRMS

    While in bridged mode I ran it up to 10% distortion and hit 1700 WRMS for quite a while before the 18 A on board breaker tripped. I thought it curious that the 15A house breaker didn't trip before the Bugera 18A one did.... This leads me to suspect the on board breaker might just be labeled for 18A for marketing and perhaps actually be set for 15A or less. This would explain how they got the UL approvals to sell this unit in North America with the 15 A IEC plug and internal 14 AWG wire. Also, my total resister power dissipation at 4 ohms is only 600 WRMS so the resisters got very hot. Most likely my power measurements under the bridged tests aren't completely accurate so the figures are to be viewed as a rough measurement. My subjective practical experience using the amp with actual cabs would agree with the values I found though.

    All in all, at this price point, this is an unequaled value. Is it really 3800 Watts? No. Is it built to the highest construction standards? No. Does it sound good, great, or better? YES! I would conclude the Bugera BTX3600 "The NUKE" is a really nice unit for a stationary practice space where it won't be moved too much and a lot of volume is needed. I believe it would travel well enough for gigs on a monthly basis but if a band was touring daily I don't believe this would hold up for many years of road abuse. At the price I paid someone might wish to purchase two for heavier road use. It's weight may prohibit people from wanting to tote a pair of them to ensure reliability though.

    IMO it really does produce a lot of clean power for an integrated bass amp and it's equally clean versatile pre-amp makes this an incredible value to those who like to use effects. I have many other decent amps I play and gig with regularly and I really enjoyed the sound of the BTX3600. I do however think I've found the answer to one of the most asked questions on TB.....

    What's the best amp for METAL?
  16. I guess I'd have to say that if you're willing to invest some time and effort beefing it up mechanically, it just might be the bargain of the century.
    Still don't want one.
    MrWolf14 likes this.
  17. Thanks for doing this! I don't think anyone (with half a clue) was expecting to see 3600 watts. The power output is very respectable indeed.
  18. srxplayer


    May 19, 2004
    Highland, CA
    Great thread. Thanks for doing this.

    I always wondered about that power rating on those. I knew that the 3,600 watts had to be a bunch of BS but the fact that you actually nailed down the true output was really intersting.
  19. Floyd Eye

    Floyd Eye Banned

    Feb 21, 2010
    St. Louis
    I know there is a guy here who is a Behringer rep. He pops up on Behringer threads sometimes. I'd like to see what his explanation for the power rating is.

  20. The funny thing is the manual and brochure both quote 3800 watts bridged @ 4 ohm when the model # and sticker on the IEC plug are both 3600 W. Really!!! You can create 200 W pk power with this amp when ran at full bore!! I love it. :smug: