#Marshall tsl 100 bias how to#
#Marshall tsl 100 bias install#
#Marshall tsl 100 bias full#
#Marshall tsl 100 bias series#

Yes they can buy you time, but unfortunately the issues will arise in the clean channel, and so on. I know all about the mods, as I was active in the early days in the development of such mods. If you have also blown a power transformer add another $300 So you are looking at prices starting from $830 (this usually covers it) I use to offer a workaround but after a recent repair I no longer offer this repairДЄ new main board last time my price from the Australian importer was $450 The board material breaks down and they start to track the high volts. These are symptoms of a defective main board, the boards that houses the power tubes and preamp tubes. If you red plate or destroy power output tubes, or you clean channel has a hum that starts off quiet and gets louder as the amp gets warmer, be prepared for a mega repair bill. I donвЂ™t want to go on for pages and pages so I will keep to the basics

#Marshall tsl 100 bias series#

I first discovered the issues with the Marshall TSL series of amps as I owned a couple I haveВ owned a couple, but after been bitten, ImВ twice shy. You only need to move it a little to make quite a big change inВ the reading so go carefully and be prepared to make an adjustment, take a reading and then make another adjustment until you get the desired reading.The Marshall TSL and DSL are great sounding amps. In order to change this reading youвЂ™ll need a small flat head screwdriver that you slot into one of the mini pots that you find on either side of the test pins. Marshall recommend a value of 0.09 for these types of amps, which means the tubes will be running hotter and could wear out more quickly. 072 was a good number to go for as you get all the breakup and it doesnвЂ™t knacker your tubes as quickly. The meter should be set to 2V DC current and you should get a reading of anything from 0.02 to 0.09. Now you get your digital multimeterВ and VERY CAREFULLY touch the black probe to the centre pin and the red probe to ONEВ of the outer pins. The centre pin is the neutral and the ones toВ the right and left are for the two pairs of power tubes. If youвЂ™re wondering why there are three pins, it because on these amps you bias the tubes in pairs. DO NOT TURNВ YOUR AMP ON WITHOUT THE SPEAKER ATTACHED!В You could blow tubes or damage the amp if you donвЂ™t have it attached. You should then let it warm up for 15 minutes and switch it off stand by. You will be using a digital multimeter to test the voltages you are getting in a moment but the first thing to do is plug in your speaker cab and turn the amp on. This is the bias test point, it is a set of three pins that stick out of the amp underneath the power tube section on the right hand side. A cool thing to note is that the lettering on the tubes all faces forward, which is another way to check that the tubes are correctly installed. Here you can see all the tubes fully installed and ready to be biased, which is the next part of the process and a very important thing to do. With the power amp tubes, thereвЂ™s a ridge on the centre pole underneath the tubes that lines up with a notch on the chassis.В You shouldnвЂ™t have to force the tubes in, so if you are not getting them to sit properly, chances are you donвЂ™t have the ridge and notch lined up. Line that up with the gap on the circuit board and theyвЂ™ll slot in nicely. On the preamp tubes there is a gap in the pins on the bottom of the tube.

#Marshall tsl 100 bias install#

When installing the tubes there are very obvious ways to install them. This was to avoid any oils or muck from myВ fingers getting onto the tubes. It contained the ECC83 pre amp tubes and Eе…ѓ4 power amp tubes, which are a classic combination for the JCM2000.ДЄs you can see I was wearing gloves when installing the tubes. IвЂ™ve chosenВ the JJ Electronics Valve pack from Voc Rock Guitars. Once youвЂ™ve done this then you should install your new tubes. As you can see there are random tubes in the back of this amp that donвЂ™t appear to be matched which could have some bearing on the fact that the amp wasnвЂ™t very happy.

#Marshall tsl 100 bias full#

This could be a simple two in two out job (you should always replace tubes in pairs) or the full re-valve that IвЂ™m doing today. Back PanelДЇirst thing to do is remove the back panel and gain access to the tubes you wish to replace. That said, the beauty with the JCM2000 is that everything you need to get at to change the tubes is visible and everything else is hidden away under panels. The voltages that are running around an amp are dangerously high and could kill you if you touch the wrong thing. ItвЂ™s important to say up front that if youвЂ™re a young un or havenвЂ™t had too much experience with electrical equipment then itвЂ™sВ probably not a good idea for you to tackle this job.

#Marshall tsl 100 bias how to#

Today I thought IвЂ™d run through how to change the valves and re bias a Marshall JCM2000 DSL 100.