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adibrook · 16th Sep 2006, 6:23 am

Its 6.08am now and i'v been sitting in my shed for like 6 hrs, building this.

Usually, i spend this part of the day watching Cops/Cheaters on channle 151 with our drummer. However, today channle 151 have become very annoying and did a whole day of stuff that wev seen before. So a new activity was needed.

I thought, even tho i'v got a number of 807's, and i'v lost interest in them, its worth at least building a prototype amp to see if 1) i'm capable of building a power amp of considerable power and 2) to actually see what the 807's are like out of curiocity.

So i built this power amp, and to be honest it aint too bad. Sounds nice, and 807's dont look TOO bad in the dark. In fact, these 807's seem to have a slight blue glow in the glass, which makes it look even nicer.

I'm using a 5Z4 rect at the moment, which is abit small i think but works. For the smoothign choke i used the primery of a mains transformer form a transistor amp, which seems to be quiet effective.

This also happens to be the 1st time i'v ever built a long tailed pair phase splitter. I used a 6SN7 and it worked 1st time no pronblem. I think the trick was to draw the circuit in a way that seemed logical to me. In schematics its usually not how my brain would consider logical. But...as soon as i redrew it i was like OOOOOOH i see and now i can build them with no problem, and feels like i'v known it all my life

.

I gave it a blast with my minidisk, and these 807's really sound ok. I doubt anyone appreciates listening to black metal at 6am, but they should be used to it by now.

So, the 807 isnt such a bad valve after all. And looks like i AM capable of building one of these. Even when slightly tired.

The search for an even cooler power amp valve still continues tho.

I will put a pic and a schematic up in the ''morning'' (3pm).

16th Sep 2006, 6:23 am	#1
adibrook Retired Dormant Member Join Date: Dec 2004 Location: Weymouth, Dorset, UK. Posts: 377	807 power amp #1 Its 6.08am now and i'v been sitting in my shed for like 6 hrs, building this. Usually, i spend this part of the day watching Cops/Cheaters on channle 151 with our drummer. However, today channle 151 have become very annoying and did a whole day of stuff that wev seen before. So a new activity was needed. I thought, even tho i'v got a number of 807's, and i'v lost interest in them, its worth at least building a prototype amp to see if 1) i'm capable of building a power amp of considerable power and 2) to actually see what the 807's are like out of curiocity. So i built this power amp, and to be honest it aint too bad. Sounds nice, and 807's dont look TOO bad in the dark. In fact, these 807's seem to have a slight blue glow in the glass, which makes it look even nicer. I'm using a 5Z4 rect at the moment, which is abit small i think but works. For the smoothign choke i used the primery of a mains transformer form a transistor amp, which seems to be quiet effective. This also happens to be the 1st time i'v ever built a long tailed pair phase splitter. I used a 6SN7 and it worked 1st time no pronblem. I think the trick was to draw the circuit in a way that seemed logical to me. In schematics its usually not how my brain would consider logical. But...as soon as i redrew it i was like OOOOOOH i see and now i can build them with no problem, and feels like i'v known it all my life . I gave it a blast with my minidisk, and these 807's really sound ok. I doubt anyone appreciates listening to black metal at 6am, but they should be used to it by now. So, the 807 isnt such a bad valve after all. And looks like i AM capable of building one of these. Even when slightly tired. The search for an even cooler power amp valve still continues tho. I will put a pic and a schematic up in the ''morning'' (3pm).