After a year building different versions of gainclones I had around something like 7 stereo versions in different places. And since now I’m on summer vacations I thought it was time to build the finished versions.
My needs are a little bit different of the average GC builder, because I’m using them in tri-amplified monitors and for surround sound in a large space, so I need a lot of clones and some of them need not to be THE amplifier, so I can compromise somewhat.
The logical decision was to think in an enclosure that could accommodate at least 6 of them. With a friend’s help we built the enclosure. You can see that the heat sinks form the sides. The shop that provided the aluminum also did the bending and cutting. After drilling and sanding it was black anodized.
The circuit is a conventional NI configuration with 220K feedback resistor and 10K to ground from NI and inverting inputs. No capacitors. For several reasons I pretty much like to use a 5W 0.22 ohms resistor at the output.
I would prefer to use toroids but they are difficult to obtain here, so I choose two conventional ones rated 24+24v 5 Amp with electrostatic shielding and metal carcasses.
For rectifiers I’ve been using different brands and types. I settled on a pair of integrated 35 amp bridges that for my own taste sound ok.
Since several amps are been feed by each transformer, the power and ground distribution is not to be taken lightly. Right now I’m wiring the first of the three enclosures and I’m running each amplifier separately from the rectifier. This configuration ended up in a mess of wires in the proximity of the rectifiers. As you can see, I’m not a neat builder. I wish I were.
Last night I tested the firs half of the first enclosure and the sound is good as expected. Been an all-metal case I was afraid of resonances, but the enclosure ended up being massive and very heavy with the transformers so I couldn’t detect problems with it.
Time for more testing.
Cheers
Ric
My needs are a little bit different of the average GC builder, because I’m using them in tri-amplified monitors and for surround sound in a large space, so I need a lot of clones and some of them need not to be THE amplifier, so I can compromise somewhat.
The logical decision was to think in an enclosure that could accommodate at least 6 of them. With a friend’s help we built the enclosure. You can see that the heat sinks form the sides. The shop that provided the aluminum also did the bending and cutting. After drilling and sanding it was black anodized.
The circuit is a conventional NI configuration with 220K feedback resistor and 10K to ground from NI and inverting inputs. No capacitors. For several reasons I pretty much like to use a 5W 0.22 ohms resistor at the output.
I would prefer to use toroids but they are difficult to obtain here, so I choose two conventional ones rated 24+24v 5 Amp with electrostatic shielding and metal carcasses.
For rectifiers I’ve been using different brands and types. I settled on a pair of integrated 35 amp bridges that for my own taste sound ok.
Since several amps are been feed by each transformer, the power and ground distribution is not to be taken lightly. Right now I’m wiring the first of the three enclosures and I’m running each amplifier separately from the rectifier. This configuration ended up in a mess of wires in the proximity of the rectifiers. As you can see, I’m not a neat builder. I wish I were.
Last night I tested the firs half of the first enclosure and the sound is good as expected. Been an all-metal case I was afraid of resonances, but the enclosure ended up being massive and very heavy with the transformers so I couldn’t detect problems with it.
Time for more testing.
Cheers
Ric
Attachments
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.