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Some Questions about a Haynes Lead II studio Amp
#1

.pdf   Hynes_Lead_II_Studio_100206.pdf (Size: 793.61 KB / Downloads: 12)

Going through some schematics I downloaded from the old Ax84 site, a few years ago. I ran across this one. Named the "Haynes Lead II studio" dated 2006. Shows a great deal of similarities to the 4-4-0 and the October power amps. But then the Pre amp is using 3 more stages. Studying this schematic I noticed the second, third, and forth stages do not have the " normal" plate  resister values. Even though they are 12AU7 valves. So, is there anybody here to have ever built this amp, and are there any sound clips? What amp is this a (emulation of) copy or clone? Then why the 12AU7 and the lower plate resister values for these stages. Super clean or what???
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#2
(01-19-2020, 04:14 PM)mcneb Wrote: Going through some schematics I downloaded from the old Ax84 site, a few years ago. I ran across this one. Named the "Haynes Lead II studio" dated 2006. Shows a great deal of similarities to the 4-4-0 and the October power amps. But then the Pre amp is using 3 more stages. Studying this schematic I noticed the second, third, and forth stages do not have the " normal" plate  resister values. Even though they are 12AU7 valves. So, is there anybody here to have ever built this amp, and are there any sound clips? What amp is this a (emulation of) copy or clone? Then why the 12AU7 and the lower plate resister values for these stages. Super clean or what???

John and I corresponded on his design a bit. His intention was to combine many stages each making small contributions to the distortion characteristics. Hence the cascade of low-gain 12AU7 stages. To my knowledge this was a ground up design, not patterned after any existing circuit.

Stph
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#3
So, Mr. Keller, sounds like you know some about this design? You mention that the stages "make contributions to the distortion characteristics". Would this be considered a metal flavored type of amp or would it have some southern Almond Bro. / Lynyrd Skynyrd growl? This design is unlike a Trainwreck, Dumble, or a Soldano. I have seen no other topography like it. So It does not compute, 4, 12Au7's low gain stages into a 12Ax7 stage. Just looks like it would be to clean. The 12Au7's are more HIFi like I would think. So please tell me what you think it sounds like. I got to know. Thank You.
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#4
Looking at the schematic, this was almost certainly designed for preamp distortion.

First, second, & third stage very similar to the HO / SEL with less inter-stage attenuation. Forth stage looks to be roughly center biased so just more amplification after the tone shaping stages. The fifth stage is where the magic is going to happen - this will be the first stage to OD and it looks like it is setup a little hot and FULLY bypassed. If you really needed more than this you could just bootstrap the CF.
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#5
Sound clip was with the schematic.

https://ax84.com/archive/ax84.com/static...LeadII.mp3
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#6
Thank You for the sound file link. Not at all what I would think it sounded like.
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