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innovine

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Everything posted by innovine

  1. Which parts, exactly, and why? Citations needed.
  2. What's a good bias for jj's in a dt25? I find it hard to understand why this is difficult, its not like there's magic and voodoo involved. The different properties of eh's and jj's should be well known, so a suggestion for a bias shouldn't be too hard. What say you, tube geeks?
  3. I still didn't find an easy source for the fuse, so I put in a 315mA fast one instead. Seems to work ok so far :)
  4. I'm pretty sure the term I mean is inductance. Reactance is the opposition to changes in current (or voltage) caused by inductance (or capacitance). A standard (high power) resistor can work as a dummy load as it offers resistance, but not inductive reactance. A coil, like in a speaker, is also inductive. Since tube amps are current sourcing, anything you connect which is inductive has a noticable impact on the signal, an impact that a simple resistor does not. The result of connecting something in.uctive is reactance, which is expected by the designer of the amp. So without inductance the dummy load causes tonal changes. This why the expensive attenuators are built on coils and motors, since they have inductance (tone preserving) as well as resistance (volume lowering). So when I said "A resistive load won't sound good, though. It needs to be inductive too" I could have added "to create the required reactance". But a coil, or the webber or whatever does not have reactance. It only creates a reactance when you pass current through it, because it is inductive. I love splitting hairs ;)
  5. Are amp techs messing with that too? Cos the only user tweakable value on my amp is the bias, apparently
  6. What bias value will let me use jj's without them melting after a few months? I did indeed bias them to 25mv which is the dt25 bias for eh tubes. So maybe line6 would like to let me know what value won't blow my tubes up. What kind of magic knowledge does a repair center have to have to get this working? I have an oscilloscope, just no deep knowledge on power amp design. I'd be happy to calibrate my amp if someone could just let me know the process. The more I think about it the more I'm going to call line6 out for bullsiht on this one. If amp techs can calibrate the amp to use jj's without melting, the why don't line6 a) publish the bias voltage and b) use jj's instead of shltty eh's which are clearly noisier. Bogner could have designed the pow'r amp to work with jj's just as easily. I bet line6 just have some kind of deal with eh.
  7. A resistive load won't sound good, though. It needs to be inductive too. The speaker has an effect on the poweramp just as the poweramp effects the speaker...that's why attenuators and dummy loads cause tonal changes due do lack of, or different inductance.
  8. All the amps in my test were well used. The dt25 was cold, sterile and brittle, for want of better terms. The ac30 was spongier, springier, somehow. And much warmer and deeper. I was familiar with the sound of my dt25 and thought it was pretty good, but a side by side test was an eye opener. Digital modelling can't replace the analog (yet) so it compensates by adding a lot of options. Whether this is good or bad is debatable... sometimes its better to have an amp with a few knobs, all of which sound good, and you just plug and play. The digital gear often leads into wasted days of tone chasing and fiddling. This debate has been done to death in the analog synth world, comparing hardware to software vst synths. Fact of the matter there is that the software synths are sounding pretty darned near, if not better at many things. Flexibility, configuration options, portability, price. You can't beat a dedicated hardware synth for jamming on and twisting knobs, thats just fun and inspirational. I think the guitar world is gonna end up very much the same... those whoewanna get the job done will be using modellers, those who enjoy their instrument for its own sake won't be satisfied without that tube tone and that simplicity of setup and use. Or they make do with a modeller due to cost.
  9. I once had the chance to set up an ac30, a park 75 and a pod/dt25 together, and dial in similar sounds on the pod to the amps it imitates. There is no comparison. Although the pod/dt25 sounds nice on its own, it had no chance against the real amps. None. Nada. Nope. No. Of course, its cheaper, and more portable and more flexible and with more options etc etc, but just sitting there on front of em and playing, the pod/dt25 was a sterile, lifeless pale imitation. So in terms of tone and feel, the modellers lose. Convince yourself otherwise if you like, or that the other factors are more important. That might be. For you. End of stupid thread.
  10. Won't that just destroy your output transformer? You shouldn't run the amp wiyh the speaker disconnected, it'll destroy the amp. The sound on the direct out is, I believe, a low level version of what's going to the speaker. If the speaker is silent, isn't the direct out silent too? Can't check, my amp is broken, but I think thats how it goes. There is only one way to get the sound of cranked tubes, and that is to have cranked tubes. Placing an attenuator or dummy load across the amps output can let you reduce or eliminate the loud sound, but the more you reduce it like this the more the tone gets altered too. Look into building an iso box or something, if LVM doesn't do it for you (doesn't do it for me anyway).
  11. Look at hardware synths, vsts, and virtual analog. Source of endless debate. Giant market. Evangalists in both camps. Learn from history. Why should guitars be any different? There is nothing to discuss, only attempts to win over converts. Yawn.
  12. Anyone know if a 400mA fuse is close enough? Screw line6 for using such an obscure value on a wear-n-tear component.
  13. That's Bogners tighter tolerances for you (aka the only way they could get it to work without melting the tubes every few weeks)
  14. The ones that don't have problems rarely post on the support forums.
  15. No, not yet. The fuse looks like it might have gone. They are unusual (thanks again, amp designer) and I've to order one on the net. Do you use noise gates? It'll cut down on the high gain amplification of noise in your guitar signal, but won't do anything for the amps noise floor.
  16. Or, to look at it another way, they couldn't prevent decent tubes from burning out. The best they could do was a noisy, hissy amp.
  17. My amp just died. Seriously!? wtf!?! You think those l6 support guys I dissed have some kind of remote activated destruct button?
  18. Just replaced the tubes, no difference. Is there some fuse that'd blow yet still run the heaters and power the backlighting, etc? Like no high voltage anymore?
  19. Talk about friday 13th bad luck. Turned my dt25 on just now and there was a loud crackle and hissing so I turned it off again. Now when I power on (in stby) it does the usual clicks and pops and the lights all come on, except for the backlighting of the on/stby and power/off which remain dark. And there's no sound of course. Any ideas? Tubes look ok, visually.
  20. I know what to make of it, and it doesn't reflect well on the competence level of their support staff, to put it mildly.
  21. Noticibly. Went from a loud hissing to totally silent (withtthe matched tubes). so quiet that at normal volume (enough to sing loudly against) it wasn't possible to tell if the amp was on or not from a foot or two away. Compare this to the irritating hiss from the stock ehx. I still have them, so a before and after recording could be easily arranged. I'm referring to the two power tubes. El84's. I didn't change the PI and there's no boost on the dt25. In my case at least, the el84s were producing a very high noise floor. The jjs are much, much quieter. And the signal louder and clearere so fantastic improvement in SNR. The hum I have now is due to the tubes not being matched, and is quiet enough for me to live with
  22. My dt25 came with ehx el34, so line6 tony is talking bulllollipop. Wouldn't be the first time..
  23. Is the orange a hd model? Is it any good for dist or is it intended for monster loud clean sounds?
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