Tronographic Rusty Box to Crown XLS 1502 to a pair of Genz Benz NEOX-212T's... any worries?

Discussion in 'Amps and Cabs [BG]' started by Jason Z Chicago, Apr 3, 2017.


  1. Jason Z Chicago

    Jason Z Chicago

    Mar 9, 2015
    Hi guys,

    Decided to go with the Traynor sound for a preamp (Rusty Box).

    Then wanted to utilize both 212T's and the Mesa Subway 800 looked like the only way to run 2ohms. Didnt like the results. Running through the effects return of the Subway was the best sound to my ears but the amp would "limit" when I cranked it above 3 o'clock. Even with the Rusty's output turned down to like 10, 11 o'clock.

    I did some research and decieded to try out a Crown PA head (class D, 2x525 watts @ 4ohms). Hoping this does the same thing as the mesa, just more watts and about $500 cheaper.

    Any issues with using this kind of amp into this kind of speaker array (2x600 watts RMS @ 4 Ohms)? Any better advice?

    Thanks so much!
     
    Crowd crusher likes this.
  2. BasturdBlaster

    BasturdBlaster

    Feb 19, 2012
    Crandon WI
    The 1502 is nice as it has selectable input "sensitivity" -- 1.4v or .775v

    I would be curious what the output of your preamp pedal puts out.........
     
  3. Jim Carr

    Jim Carr Dr. Jim

    Jan 21, 2006
    Denton, TX or Kailua, HI
    fEARful Kool-Aid dispensing liberal academic card-carrying union member Musicians Local 72-147
    I see no problems, and I know the Mesa 800 has a soft limiter, but I am confused about cranking the Master "above 3 o'clock." If you are plugging your bass into the Rusty Box, and the Box into the effects return, are you saying your master volume still works but limits too much at 3 0'clock?
     
  4. Jason Z Chicago

    Jason Z Chicago

    Mar 9, 2015
    On the Rusty Box - theres two options, one is "line out" which disables the volume knob (for recording and direct box stuff) and the other is "instrument out" which is for using it as a pedal going into a real preamp/amp. I have never heard of the volts thing before with input sensitivity. Just decibels. I can write the Tronographic fellas and ask.

    Whats the typical scenario with other preamps/direct boxes, as far as volt sensetivity? like a Sansamp or something.
     
    Last edited: Apr 3, 2017
  5. Jason Z Chicago

    Jason Z Chicago

    Mar 9, 2015
    You have it right. The Master volume on the Subway would stop getting louder about 3/5ths of the way turned up. The little limit light would come on and ruin my fun.
     
  6. charlie monroe

    charlie monroe Gold Supporting Member

    Feb 14, 2011
    Buffalo, NY
    The only prob I see is melting faces. Pretty sure the RB can drive an amp.
     
  7. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Then you don't have enough rig for the gig.

    If you need more power per box, you probably need more speaker as well. You must be talking about some really loud playing, or a lot of very low end.
     
  8. BasturdBlaster

    BasturdBlaster

    Feb 19, 2012
    Crandon WI
    I believe (please someone correct me if I'm wrong) .775v=0dBu

    :)

    taken off the web.......

    For electronic calculations (voltage and wattage) the 0 dB references are: 0 dBu (or dBv) = 0.775 volts 0 dBV = 1 volt 0 dBm = 1 milliwatt (0.001 watts). The standard reference value for 0dBm is 0.775 volts into a load of 600 Ohms. For most audio calculations, simply assume you are NOT using a 600 Ohm load and thus dBm can equal dBu. For example, a +24 dBm output specification on a mixing console can be used as +24 dBu to calculate voltages. The reason for this is that modern audio equipment will put out the same voltage whether there is a "load" on it or not. Thus knowing the power in a line level audio circuit is of little value and simply complicates what you need to know. Example: 6 dBu is the ratio of some voltage divided by 0.775 volts. That voltage is 1.55 volts.
     
    Jason Z Chicago likes this.
  9. Jason Z Chicago

    Jason Z Chicago

    Mar 9, 2015
    I figured 4x12's stacked on top of each other would be enough to move the air, especially at ear level due to the height. The idea here was to stay lightweight and get as loud as I could. We tune to D and I focus on mids so were not terribly low hz.

    I looked at some lightweight 8x10's but the barefaced is over 2 grand and the fender still weighs 110lbs.

    I was just surprised the Mesa said "thats enough" like a rude bartender. Its 800 watts at 2 ohms and the cabs I was running were 1200 watts @ 2 ohms. I thought the Mesa could turn 100% up without anything holding it back. Hoping the Crown will ante up. Its about 250 more watts and has bandpass so I can lose the lowest of the low end and focus more power to the 80hz-4khz range, I hope!
     
    Last edited: Apr 3, 2017
    BasturdBlaster likes this.
  10. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Common misconception, rated output can be achieved at way less that 100% pot rotation because it is also dependant on how hot the pickups are, the set-up of the instrument, and how hard it's being played. Did you have the Subway set to the 2 ohm position?

    Which model Crown, I'm not sure you are stating it's rated power correctly.
     
  11. charlie monroe

    charlie monroe Gold Supporting Member

    Feb 14, 2011
    Buffalo, NY
    XLS1502, according to his thread title.
     
  12. Jason Z Chicago

    Jason Z Chicago

    Mar 9, 2015
    Yep, I had the Mesa set @ 2 Ohms.

    Crown 1502 is 2 x 525 @ 4 Ohms
    upload_2017-4-3_15-5-19.png
     
  13. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Sorry, I got two threads mixed up.

    Should be a reasonable matchup, but only responsible for about a dB more SPL. You might prefer the limiting method in the Crown better (or worse), but regardless I would recommend ear plugs.
     
  14. Jason Z Chicago

    Jason Z Chicago

    Mar 9, 2015
    One last question about this, if I may: would it be irresponsible to use the Crown 2002 model (650watts) on a cabinet rated 600watts? Would that 50watts blow my speakers? And Im guessing it would only add another db of SPL? Just my greedy instincts kicking in here, trying to get the absolute most out of these two genz benz 2x12's.

    Again, thank you all for the great help!!!
     
  15. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Not even a half dB.

    At that power level, if driving hard, you will want to exercise some caution. This applies to all speakers as a general statement.
     
    Jason Z Chicago likes this.
  16. dcarwin

    dcarwin

    Feb 11, 2013
    415
    More watts in the amp is safer than less watts. Ask someone who has regularly blown speakers...

    The Brian Gibson Interview: Lightning Bolt’s Low End

    ME: Do you remember what you were using before and what kept blowing up and what you ended up purchasing?

    BG: I initially had a Hartke 3500, a 350 watt amp, and I had an 18” sub and a 4×10 and the Hartke was frying all the time and the speakers were frying all the time and then when I came back, I got an Ampeg SVT Pro 4 and that’s like 1200 watts…

    ME: Yep, that’ll do it.

    BG: …and then I got two subs and two 4×10 so I kind of doubled the size of the rig because there were just more speakers I could hear myself over Brian and less prone to blowing stuff. I mean, I still blew stuff a lot. It took me another 5 years to learn how not to blow up speakers all the time which was by getting super powerful amps.

    Now, I have two 3,000 watt amps. Weirdly the more power you have the better it is for your speakers because what’s really bad for your speakers is going into the red. It’s not really watts necessarily.

    ME: It’s just how you’re overdriving the speaker and for how long.

    BG: Yeah, being in the red causes it to clip and these square wave signals that burn your coil.

    It’s a weird thing with speakers. I had always thought I needed to get an amp that wasn’t too many watts and speakers that could handle a ton of watts and that would solve the problem. But even a really powerful speaker if I was cranking an amp into the red, I’d still blow it and it was really confusing for me.

    Over the years, I’ve learned the discipline of matching the speaker watts to the amp watts and just having a super powerful amp. So you can get as loud as you need to get and you’re still in the green.

    I used to go far into the red and just blow up a speaker in like a week.
     
    Jason Z Chicago likes this.
  17. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Ultimate face-palm... this has been addressed multiple times with some pretty good stickies at the top of the forum.

    I typically see WAY more speaker damage from over-powered rigs, especially rigs that are not adequate for the task.
     
    SunnBass likes this.
  18. dcarwin

    dcarwin

    Feb 11, 2013
    415
    >> I typically see WAY more speaker damage from over-powered rigs, especially rigs that are not adequate for the task.

    Your use of the word "rigs" is confusing here. Does rigs refer to amplifier (as in "overpowered") or does rigs refer to speakers (as in "not adequate")? If it's amplifiers, can a rig simultaneously be both overpowered and not adequate for the task? It's surprising to see an engineer be so smudgy with terminology.

    I simply quoted a professional musician, who has dealt with the issue for years with his own money, providing his story about arriving at what works for him at sustained high-volume. You can perma-facepalm if you wish.
     
  19. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Rig as in speaker's and amp(s) together not able to generate the desired volume.
     
  20. I've been running a crest prolite 2.0 (550 watts) into a 410 hlf (500 watts) for a year now with 0 problems. I run a compressor as a limiter in my rack to take out the peaks for my iems and speaker so that helps when I backline and ppl of different volumes plug in. I have never been able to turn the amp up higher than 6/10 though because it overpowers the guitarists at that point. We keep stage volume relatively low. It's still really loud though.
     
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  21. Primary

    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

     
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