15-08-2020, 07:14 AM
Here's my latest valve amp, nearly finished bar a few finishing touches like finding some decent knobs. Still working on the frequency response hence tacked in cap, also have to fit zobel networks and a few other doodads.
As per my hifi why bother thread I designed this amp to sound "nice" and didn't worry to much about THD, in fact I designed it to have a strong 2H component. THD is less than 0.5% at 30w, rising to 2% at 50w, again 2H dominant.
Amp has over current protection, slow/soft start, hand wound mains toroid ( wound twice cos someone burnt a winding out), OPT's from Joe in Oz, Joe also kindly sent me 12 807's NOS still in their tropical packaging. At present it runs in Class A apart from the last 10w or so, but I might add sw's so the OP can be switched to UL. As you can see I've committed the sin of including tone controls, design is Rod Elliots hifi preamp using 5532 opamps.
Here's some pics. Andy.
As per my hifi why bother thread I designed this amp to sound "nice" and didn't worry to much about THD, in fact I designed it to have a strong 2H component. THD is less than 0.5% at 30w, rising to 2% at 50w, again 2H dominant.
Amp has over current protection, slow/soft start, hand wound mains toroid ( wound twice cos someone burnt a winding out), OPT's from Joe in Oz, Joe also kindly sent me 12 807's NOS still in their tropical packaging. At present it runs in Class A apart from the last 10w or so, but I might add sw's so the OP can be switched to UL. As you can see I've committed the sin of including tone controls, design is Rod Elliots hifi preamp using 5532 opamps.
Here's some pics. Andy.
