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Tweaks for systems, rooms and Do It Yourself (DIY) help. FAQ.

Re: Inside of Gaincard?

Hmmm...I don't know how to feel now. On one hand, the Gaincard is very cool - I think it has a great form factor, and it sounds really good. Looking inside, though, I can't help but feel a little ripped off. I say "a little" because I still think the Gaincard is cool in form, and it sounds great, but it just looks so cheesy on the inside.

Understandable.

When you hear that it has only nine parts in the signal path, that sounds really wonderful. In fact, that simplicity has real appeal to it. Then when you see it, it hits you and you realize just how simple it is. In fact, it's so simple that if I didn't have one, and knew what I know now, I'd go ahead and build one from scratch myself! In fact, I might just do that anyway.

Actually they don't claim it has only nine parts in the signal path. Just nine parts in the basic circuit. And I've been rather critical of that nine parts claim. I think it's highly misleading when you consider that one of those parts is the power opamp itself which ultimately comprises literally dozens of parts and a circuit topology at least as complex if not moreso than many discrete amplifier designs.

So it's really nowhere near as simple as they'd have people believe. The complexity is rather out of sight and out of mind. If you want REAL simplicity, then you need to look at something like a SET or say Nelson's Son of Zen.

Anyhow, the point is moot. I already have the Gaincard and enjoy it greatly, and now I have enough information to make a decent clone if I wanted. I guess that's all I can ask for at this point.

Absolutely. Ultimate enjoyment is all that matters in my opinion.

One thing though: I'm still very impressed with the power transformer. I would really like to find one of this quality.

I'm still trying to figure it out. What you describe sounds like the core is made like that of a toroid (i.e. a coiled ribbon) but has windings more akin to that of an EI core. Although I'm giving up on AC entirely, I'm still rather curious about the transformer you're desribing.

Also, I'm itching to experiment with new resistors and capacitors. I've alway liked the Shinkoh tantalum film resistors but don't think they make them this small. The smallest tantalums that I've seen are 1/2 watts (Shinkoh and Audio Note) and I know these are quite a bit bigger than the ones pictured. Also, I wonder if these would be too detailed for a crisp and clean sounding design like the GC. Perhaps the Riken Ohm carbons films (which are smaller) or the Kiwame would be a better choice. Also, I wonder if Black Gates or Cerefine would make a good cap replacement.

That's an area I stay well away from as I believe you're the only one who can provide a truly meaningful answer for yourself.

About your experiments with the hybrid devices: do you have any links or leads to good designs using these?

You know I haven't come across anyone, commercial or DIY that's using hybrids. As to why that is I can only guess. One is that hardly anyone is aware of them and another is that they're very expensive relatively speaking. The ones I'm currently using are the Apex PA-16s which go for a little over $90 a pop.



The circuit I'm using in my current amps is about as simple as it gets. Just a Jensen JT-11P-1 input transformer, a 10k load resistor across its secondary, a pair of resistors for the feedback network's voltage divider and a pair of current sense resistors (part of the PA-16's design). That's it.

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