Fri May 23, 2008 2:16 pm by drewideth
Well, I have a solid background in generic solid state and tube amplifier topology and am very fluent with the TFM, A, and AV series amplifiers. On the aspect of repair, a circuit is a circuit, and each individual component is doing its job to specifications or it isn't. So some manufacturers use an unregulated power supply and some use a regulated, some use a triple darlington output array and some use an intergrated transistor, but fundamentally they are all using basic solid state components to create their circuit and those components have to operate under certain conditional laws that are easily tested. There are many circuit configurations that I am not familiar with, though I am familiar with all of the components that they are made of. I am not saying I can fix anything but I do have a 98% success rate over the past three years and there is no charge if I can't fix it minus S&H.
When it comes to cross-overs, that's where the fun begins. I have a couple of designs for the Amazings, but I have not had a chance to dig into any ALIII's yet. X-over design just takes time, listening, and a component hot swap helps a lot too. If you allready know what points and slopes you want and also what type of network (butterworth, zoble, etc.) I would be more that happy to build them for what ever power application and impedence you like. As for the components, some like Aura caps vs. Janzten and so on, but you have to be careful to use the right "spices" because ice cream doesn't exactally taste good with oregano.
As for an example of pricing, I just reapired two TFM-6CB's for a local customer. One had a bad toroid, and the other's output stage went into meltdown to the extent of replacing all eight output transistors with accompaning shunt resistors and the protection relay also I had to reair a few parts of the PCB that had been burnt through. Fortunally, I was able to get the toroid fairly cheap and was able to repair both amps for about $160.00 parts and labor.
I also offer a few designs of my own, both tube and solid state all hand-wired amps and preamps. For home, studio, and guitar.
Thank you very much for your replies and interest.
