BA-3 Amplifier illustrated build guide

I really am not the right person to ask, because:

1: I haven’t heard Mightys (Zen Mod) beast myself
2: I have never tried the BA-3 purely as a preamp.

But there are some major differences that might affect choice between them.

BA-3: Feedbackless push pull gain stage able to swing everything, a real preamp with an exotic feedbackless circuit. Hard to find something like it, really. Has it quirks, but once dialed in can give the listener/builder exactly what they themselves choose, be it sugar or not, wide or deep soundstage, or focused, or something in between. Intensely natural sounding. And with proper bias, never ever a contributor to harshness no matter what distortion setting.

Waynes linestage: Wayne is wayne. Push/pull, high bandwidth, low distortion without becoming clinical OTOH a bit sweet sounding. Linestage with mid level gain, compatible with a wide range of amps. Miniature JFET soldering quality is very, very important for a stable circuit.

Pumpkin: check it out: Iron Pumpkin ; line preamplifier , SE and Balanced iterations – Zen Mod Blog

Inductive attenuation, super-symmetrical (SUSY), adjustable gain. No sugar according to Mighty maker, but plenty ways to add that. This is the preamp I am going to build in the end, not knowing when of course.

In addition to that, B1 Korg nutube is on my list as a must try. Along with so many other things :cheers:

Conclusion? Impossible :rofl:

Depends mostly on your preferences, and also upstream components, power amp and speakers (ie what sound signature do you like, how might the chosen preamp contribute to that, how much voltage swing (ie gain) is ideal for your combo of power amp and speakers, how complex or easy do you want the build to be, and how cheap/expensive? You want a stable easy to adjust circuit, or something with a lot of flexibility and hence a bit of a challenge too?

Only you can decide in the end. Some say try em all. That is not realistic in my case, so I have to read up, ask and try a few selected builds as things are now :)
 
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The conclusion is simple. Build both. Wayne's will be easier, but have less gain, in standard
form. Also consider the Iron Pre, transformer gain, 6dB or 12dB. Power supply and relay switching all on the same board. See the "Keep it simple" thread. Very nice, some of us have built beta versions, not in store yet, but will be eventually.

Russellc
 
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hydrovac - re: the transformer. What version do you intend to build? The answer is in Nelson's article re: rail voltages and suggested VA rating for the two main iterations. Depending on the version +- 24VDC rails (from ~18VAC) and a 300VA transformer may not be what you want. Read the article, then post any further questions.
 
I would like to add a manual muting circuit to my amp. I was thinking of having a switch that would control relays that would disconnect the outputs (maybe disconnect the inputs, too, so the amp wasn't "amping" while muted?). Would such a scheme work, or would it lead to pops when breaking/making the connection?