Rob Karloff Posted February 16, 2004 Report Share Posted February 16, 2004 Hey folks,I now have in my posession some documentation on how to bias DSL/TSL series Marshall valve amps, and how to reduce the output of your 100W head to 50W to allow you to drive the amp harder at lower volumes. Both biasing and power reduction are simple to do, and only require a good multimeter and a couple of screwdrivers. Quote Link to comment Share on other sites More sharing options...
Tav Posted February 16, 2004 Report Share Posted February 16, 2004 Sounds interesting. I am on the search for circuit diagrams and parts list for the above amps. I currently have a few sets of fenders and various Mesa's that I am considering having a go at building. Quote Link to comment Share on other sites More sharing options...
David Posted February 16, 2004 Report Share Posted February 16, 2004 do you have stuff on the DSL401 (or indeed any of the combo versions) or only just the heads?if you have the combo versions too, would i be able to get a copy of it, mainly so i can do the biasing myself when it comes time for a retube?David Quote Link to comment Share on other sites More sharing options...
Tav Posted February 16, 2004 Report Share Posted February 16, 2004 Hey David what's your 401 like volume wise? Quote Link to comment Share on other sites More sharing options...
Rob Karloff Posted February 17, 2004 Author Report Share Posted February 17, 2004 ANY DSL/TSL series amp.The amps are exactly the same between combos and heads, it's just that the heads use a bigger output transformer to drive a greater number of speakers. Biasing a 50W or a 100W involves the exact same process, it's just that the voltages you have to set are half the value on a 50W of what you set on the 100W model.Like everything else, do it at your own risk, and if you're not totally sure what you're doing, then don't attempt it.Send me an email address, and I'll send you the PDF. Quote Link to comment Share on other sites More sharing options...
Tav Posted February 17, 2004 Report Share Posted February 17, 2004 cold_spoon@hotmail.com, hit me! Quote Link to comment Share on other sites More sharing options...
David Posted February 18, 2004 Report Share Posted February 18, 2004 Originally posted by Tav:Hey David what's your 401 like volume wise? loud enough, i had it nicely cranked last time i played in kef, which was a nice volume for gigging (possibly a little louder than i will next time, but fine) I dont see why you would really want a bigger amp, unless you intend playing jazz in wembly... and its pretty cool for bedroom volumes too, plus its a lot easier to cart about than a head + cab i love the amp basicallyand rob, could you send me the PDF to the_enema@hotmail.com, much thanksDavid Quote Link to comment Share on other sites More sharing options...
Tav Posted February 18, 2004 Report Share Posted February 18, 2004 Kef is all very well and good but you can use a Marshall MS-2 in there and have it loud enough when mic'd. Ever used it in Drakes? How did it fare there with no mic'ing? Quote Link to comment Share on other sites More sharing options...
David Posted February 18, 2004 Report Share Posted February 18, 2004 Originally posted by Tav:Kef is all very well and good but you can use a Marshall MS-2 in there and have it loud enough when mic'd. Ever used it in Drakes? How did it fare there with no mic'ing? sorry, the only time ive played there was before i got this amp so was borrowing a friends (AVT100 to be exact) but i would have no worries with the amp being underpowered, i would be slightly worried if you wanted perfect cleans at full blast, but for most people it would be fine with the gain on the clean channel up a bit and getting warm/slightly overdriven if anything more than disty compared to distorted it would still be good live as cleanfully distorted its putting out about 45 watts, which is almost 50 watts, so the difference between the 401 combo and 50 head is not very much at all, the extra speakers would help a bit, but you can always run it with a cab too... so i would have no worriesone thing to note, 40 watts dosent sound much, but since its a valve amp its quite a bit louder than a ss equivalentDavid Quote Link to comment Share on other sites More sharing options...
Tav Posted February 18, 2004 Report Share Posted February 18, 2004 Yip just considering amps to buy and like the portability of a combo though I don't want to get an amp which can't cope with loud volumes in a jam or at drakes if it ever comes to using it there. Quote Link to comment Share on other sites More sharing options...
Guest operator zero Posted February 18, 2004 Report Share Posted February 18, 2004 send it to healthofmind@hotmail.com don't have one but i like the thought of knowing how to do biasing. Quote Link to comment Share on other sites More sharing options...
Rob Karloff Posted February 19, 2004 Author Report Share Posted February 19, 2004 The docs only relate to the recent DSL/TSL series of Marshalls. Older Marshalls involve much more technical tinkering to do the job. It's just that on this series and onwards they provided a nice simple and accesible method of doing the job. So, the docs tell you how to bias DSL/TSL series, but not "biasing" any valve amp. Still want them? Quote Link to comment Share on other sites More sharing options...
David Posted February 19, 2004 Report Share Posted February 19, 2004 Originally posted by Tav:Yip just considering amps to buy and like the portability of a combo though I don't want to get an amp which can't cope with loud volumes in a jam or at drakes if it ever comes to using it there. its more than enough to compete with a drummer for jamming or anything, and i am pretty happy it would be fine in drakes. as i said before, the only problems i could see was if you wanted to play super clean jazz or something at full blast, but for anythign else, its coolDavid Quote Link to comment Share on other sites More sharing options...
Tav Posted February 19, 2004 Report Share Posted February 19, 2004 That's groovy cheers for the info. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.