Dan_Nailed

[quote name='Mr. Foxen' post='447015' date='Mar 27 2009, 11:19 AM']Guitarist has used both mk1 and mk2, the fact you have seperate EQ for each channel is pretty much vital, you don't want your clean/ crunch with the same EQ settings as the gain channel, if you want to do things other than sound like Van Halen. Granted the clean channel isn't great, buta clean channel with the same eq as our guitarists gain sound would be dreadful (is dreadful, heard it). Actually, the MXR compressor helped a lot with the clean.[/quote] But due to the setup on the 5150 2, it's more flexible but has a much worse overall sound, the gain especially is nowhere near as flexible and articulate as a normal 5150. Andy Sneap backs me up on this. And if you're adding a compressor to clean up a terrible clean channel, why not do the same thing with an EQ pedal on the 5150 to change the lead channel? It's swings and roundabouts.

[quote name='fede162162' post='446820' date='Mar 27 2009, 02:01 AM']Hi guys, I don't know what to choose. Soundtech pros: weight: 11kg less than the QSC space: 1U less than the QSC QSC pros: THE NAME: everybody says me that QSC is synonim of high quality the price: 80£ less than the Soundtech the power: the QSC can go bridged at 4 ohm, the Soundtech only at 8ohm I don't care about the power, I don't think I'm gonna need more than 400w. I care about the sound above all, and ,secondly, about the weight.. do you have any advice?[/quote] QSC all the way!

[quote name='Hamster' post='446814' date='Mar 27 2009, 01:33 AM']You've got me interested now! - have you got a schematic for the mod you've done - or can you direct me to who did it for you? Cheers[/quote] It's not mine, my amp came with a brand new set of Mesa 6L6's so I won't have to look at retubing for at least 2 years, that's a guy off Talkbass's but I'm sure Dave Lunt in Stockport could acomodate you, he's mentioned to me that he's converted a Bass 400 or two before and they're similar amps. His number is 07966 263 616.

[quote name='alexclaber' post='446672' date='Mar 26 2009, 10:56 PM']Good rant and in line with most of what I've picked up about valve amps. If kept correctly biased power tubes should outlast the electrolytic caps! To head off on a tangent, would I be correct in presuming that Class A valve amps don't have adjustable bias because the valves always have full current running through them? And Class B (as used in radio transmitters) have no idle current at all? Alex[/quote] I haven't read up on this for a while, but it would make sense for Class A as premaps are always singled-ended Class A circuits and don't require any Bias. I always thought Class C was for radio transmitters...Class B does have bias, but the bias is set such that when idling, the tube actually turns off and lets nothing through. Basically: A - Never turns off B - When idling, lets nothing through A good, but dense, read on this is available [url="http://www.mesaboogie.com/US/Smith/ClassA-WebVersion.htm"]here.[/url]

[quote name='Mr. Foxen' post='446655' date='Mar 26 2009, 10:47 PM']That isn't true, the original 5150 didn't, but the Mark II, which is the one to have, due to seperate eqs on channels, has bias sockets on the back.[/quote] No it isn't, the mark one is far better! No terrible solid state clean channel. Unless you mean the 6505 series, which are a different beast. [quote name='Hamster']I think you might be talking about just the Peaveys here, because I've had a long & hard look at my Mesa's schematics and as far as I can figure out the only way to convert Mesa's to adjustable bias is by a substantive board re-design, not a resistor swap-out.[/quote] This is a variable bias mod on a 400+, doesn't look like a board redesign to me... As for the colour coding Mesa thing, it just means that they've tested and graded the tubes with their own arbitrary system. Most decent valve sellers (Bob at Eurotubes definitely) can supply you with some drop-in tubes that will work with any fixed bias amp, as they've had these amps on a bench usually and have measured what their native bias is. They then rigorously test their stock of tubes and catalogue where their natural bias point is currently sitting, and mark them as suitable for certain fixed bias amps.

Just to weigh in with my views, biasing an amp is NOT something that only a tech can do, and NOT soemthign you should always factor into being a running cost of a valve amp. Valves do not "wear out" at all. Their electrical needs change slightly over time and several manufacturers, most prominently Mesa Boogie, have used this to sell more of their valves, by fixing the bias in their amplifiers so that when the tubes age the amp doesn't sound as good. The customer goes and buys new tubes. Basically, biasing is all about giving the valve enough juice while it is "idling" i.e. not doing anything. This is a DC voltage measurement. Here are some vieos on setting bias and a little more info, the Eurotubes ones are especially no-bullshit: [url="http://www.eurotubes.com/euro-video.htm"]http://www.eurotubes.com/euro-video.htm[/url] - click links [url="http://www.expertvillage.com/video/68249_tube-amplifiers-biasing.htm"]http://www.expertvillage.com/video/68249_t...ers-biasing.htm[/url] Not all amps have an adjustable bias, Mesa don't, and Peavey 5150 amps don't for example. These can be converted for what should be a small fee by any decent tech, from which point on you can bias your own tubes. The job basically involves replacing a fixed resistor with a variable resistor. The upside to this is firstly one of cost - when your tubes age, you can re-bias them and save yourself a ton of money on power tubes. On my Mesa 400+, 12 matched 6L6GC's will be about £100-£120, if they're JJ's. Mesa's are more expensive as they have some white paint sprayed on them in the shape of a Mesa logo. This stunning piece of graphic design adds about 20% to the cost. A driving factor in these costs is that the tubes have to be tested by the vendor and matched to the particular fixed bias that comes in the particular amp, people like Lord Valve, Bob @ Eurotubes and Watford valves do this for you, why? Because not all tubes come out of a factory with the same tolerances. Hence, having adjustable bias means you can get any tube and make your amp work with those tubes within it's acceptable limits. Many lazy players might see this as a lot of hassle, but then again I'm guessing most decent bass amps come with adjustable bias from the factory. So to save yourself hundreds in tube costs, al you need to invest in is at worst a multimeter from Maplins, some bias probes from Eurotubes or similar, and a small screwdriver to turn the bias knobs. Now I'm not saying a valve will last forever - it is an electrical component and will suffer wear, but then again so will anything. Even if you only change tubes half as much, you're saving twice as much money. Another advantage is that you can tweak your amp's tone through the bias setting, hotter for more breakup and so on. /rant Valve amps are a little more work, they're a little more fragile and they don't like being turned on without a speaker plugged in, but if they work for you then these are small prices to pay. Weight wise, my Bass 400+ in rack weighs the same as my old SVP-Pro + QSC setup. An SVT2 is worryingly heavy though!

MXR M-80 will get a very close tone to that, both IME and on this video: [url="http://www.youtube.com/watch?v=qv3baLNG-10"]http://www.youtube.com/watch?v=qv3baLNG-10[/url] Warning, the guy in the video is a redneck. Rex Brown also uses the M80, his "settings" are in the back of the manual. I'm not saying it'll be the answer to your question but it'll get you a chunk of the way.

[quote name='umph' post='441278' date='Mar 21 2009, 08:01 PM']haha they use vettas though which are the grand daddys of line 6 stuff and are going back to proper amps now. They also have they're own sound engineers all the times i've heard people using line 6 pod xts live they've sounded terrible[/quote] Actually when I saw them the last few times they haven't used any extra monitoring, just the usual wedges that the venues usually have in-house. The singer had in-ears but the other guys didn't, and no side fills either. I've seen about 6 people use POD XT's, half were using the floorboard model and the others had rack units. Only two of those times did they sound good, mainly because the players knew how to actually set the patches up and had some understanding of how mixing works. So it is definitely possible. Most stage monitors are 12"s and not much different from the 12"s in backline instruments, there's only so many ways to make a speaker anyway, and while they can't exactly hack kick drums for prolonged periods I have had many a synth go through one. Just roll a little bottom off the monitor and all's well.