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Joined 2009
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Yes, well spotted - its an old E-I tranformer salvaged from a broken AV receiver. It outputs 60VCT, which translates to approx. 40VDC rails loaded. There are no power ratings printed but judging by the size and weight I would estimate 150-200W. A powerhouse by no means but ample for casual listening.
When I buy (as opposed to salvage) transformers I opt for toroidals due to availablily and cost/weight considerations. You'll see with most of my builds that I mount the heatsink inside the case, positioned between the transformer and amplifier boards / low level signal carrying leads. My theory is that the big lump of aluminium and physical seperation helps shield the circuit from EMI originating from the transformer. I've built designs that end up with a dead silent noise floor when other constructors report problems - so I'm inclined to believe there is credibility to this theory.
PS: I'm working on your boards and should have them finished soon ;-)
When I buy (as opposed to salvage) transformers I opt for toroidals due to availablily and cost/weight considerations. You'll see with most of my builds that I mount the heatsink inside the case, positioned between the transformer and amplifier boards / low level signal carrying leads. My theory is that the big lump of aluminium and physical seperation helps shield the circuit from EMI originating from the transformer. I've built designs that end up with a dead silent noise floor when other constructors report problems - so I'm inclined to believe there is credibility to this theory.
PS: I'm working on your boards and should have them finished soon ;-)
Quote from Rod's public P68 page:
"C11 does not exist on this schematic, so don't bother looking for it. It was "mislaid" when the schematic was prepared, and I didn't notice until someone asked me where and what it was supposed to be. Sorry about that."
If you have purchased any of Rod's products you will have access to the "construction pages" that have all the details for construction of this amp including the location of C11.
regards
Agreed. I hope i will use 5.1 Audio Gear Dolby Digital Sound Decoder. But i found some decoder has Optical (SPDIF), Coaxial, LR analog as input and it's providing 5.1 analog output. All these are availabe in my TV or BD player. I want to know which input type will give me best audio experience. According to that i will finalize the 5.1 Audio converter.
Hi PingPong
I'm very pleased with the TGM8 boards I've made, so much so that I built a stereo amplifier in a nice case for my living room.
I've built several P3A amps (experimenting with different component substitutions), VSSA, DX MkIII, and others that don't come to mind at the moment. This design of Gareth's is definitely one of the best. I have made some listening impressions in this thread.
Since you are in Australia too, I should mention that I have a few spare boards if you're interested - Gareth and I each ordered 10pcs from his board house. Happy to pass on a couple at cost price if you decide to build.
I'm very pleased with the TGM8 boards I've made, so much so that I built a stereo amplifier in a nice case for my living room.
I've built several P3A amps (experimenting with different component substitutions), VSSA, DX MkIII, and others that don't come to mind at the moment. This design of Gareth's is definitely one of the best. I have made some listening impressions in this thread.
Since you are in Australia too, I should mention that I have a few spare boards if you're interested - Gareth and I each ordered 10pcs from his board house. Happy to pass on a couple at cost price if you decide to build.
Hi Ranchu32, how much is cost price and would you have any spare matched parts available... thanks
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Member
Joined 2009
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Just an fyi - TGM8 doesn't require any matched parts
Note that if you want to get full functionality from the speaker output relay indicator LED, it needs a small 'fix' (read back through the thread for details) if you want to mount it on the pcb.
Also suggest you are particularly careful to ensure you solder the power devices to the board only after first mounting them to the heatsink so that they are all held flat and co-planar before you solder their leads. Once soldered they are almost impossible to remove without clipping their leads off and removing the stubs left in the holes one at a time - this is an issue with any through-hole-plated pcb by the way and is not unique to TGM8.
Note that if you want to get full functionality from the speaker output relay indicator LED, it needs a small 'fix' (read back through the thread for details) if you want to mount it on the pcb.
Also suggest you are particularly careful to ensure you solder the power devices to the board only after first mounting them to the heatsink so that they are all held flat and co-planar before you solder their leads. Once soldered they are almost impossible to remove without clipping their leads off and removing the stubs left in the holes one at a time - this is an issue with any through-hole-plated pcb by the way and is not unique to TGM8.
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