S.I.R. 100W SuperLead Schematic pt. II

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Unique
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Re: S.I.R. 100W SuperLead Schematic pt. II

Post by Unique » Mon Nov 05, 2018 1:13 pm

BRMSlash wrote:
Sun Nov 04, 2018 3:24 am
Moved the NFB to the 8ohm tap. Changed the PPIMV resistance to a measured 220k-230k using a 1M resistor over the pot. Got rid of the cathode bypass cap and the snubber on the 3rd stage. Upped the 1st stage snubber cap to 220p. Got rid of the grid resistors on 2nd & 3rd stages. 3rd stage hot shield removed. Upped the 1st stage coupling cap to 22n. Final stage voltage divider returned to a more typical 470k//470p-470k arrangement. Increased the PI B+ node voltage.

http://sclk.co/s87ths
Very nice! What mic are you using to record with? One thing I've noticed with your samples is that you have good mic placement. I'm assuming you pretty much keep it in the same place when you record? Moving that mic just a little bit can completely change the sound on a recording, but it sounds pretty consistent in your recordings.

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Re: S.I.R. 100W SuperLead Schematic pt. II

Post by BRMSlash » Mon Nov 05, 2018 10:08 pm

Thanks. I'm using an SM57, positioned about 25mm away from the baffle, aimed at the outer edge of the cone at a slight angle. Yeah, the placement is very sensitive. I've got it set up on a mic stand that has it's feet butted up against the cabinet. This helps me position it back to the same spot if I happen to move my cabinet. I haven't moved it for some time, so as you mentioned, all the clips should be fairly consistent.

Unique
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Re: S.I.R. 100W SuperLead Schematic pt. II

Post by Unique » Tue Nov 06, 2018 9:55 am

BRMSlash wrote:
Mon Nov 05, 2018 10:08 pm
Thanks. I'm using an SM57, positioned about 25mm away from the baffle, aimed at the outer edge of the cone at a slight angle. Yeah, the placement is very sensitive. I've got it set up on a mic stand that has it's feet butted up against the cabinet. This helps me position it back to the same spot if I happen to move my cabinet. I haven't moved it for some time, so as you mentioned, all the clips should be fairly consistent.
Your welcome. That's a great idea about having it set up against the cabinet in a way that helps you to keep in the same place. I couldn't help but noticed the consistency on your tracks with your recordings. I also figured you were using a SM57. That's what was used for Slash in the studio from AFD to SI, and probably at least first Snakepit album, as Mike Clink was the producer for these albums and has stated that's all he used on Slash's tracks. So if your going to try and nail the sound in a sample recording this mic is key as other mics will have a different sound and frequency response. So good choice! This is a great mic, and I love it for guitars.

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Re: S.I.R. 100W SuperLead Schematic pt. II

Post by BRMSlash » Wed Jan 09, 2019 6:24 pm

I've made some progress. I've discovered the joys of Nichicon UPM / PM electrolytics as cathode bypass caps. They come in 0.47uF & 0.68uF capacitances! I'm liking a 0.68 UPM in the 1st stage cathode. Having a 0.47 UPM in the 4th stage works as well, but seems a bit too much in combination with the 1st stage electro. So I'm currently using a 0.68 UPM in the 1st stage, 0.1 MKT1813 in the 2nd stage & 0.47 MKT368 in the 4th stage.

Also managed to get hold of some 716p's for the presence cap. Very nice! Currently running in a 0.1uF 200v, but I also have the 400v to try.

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Re: S.I.R. 100W SuperLead Schematic pt. II

Post by CoffeeTones » Wed Jan 09, 2019 10:09 pm

I've had some of the Nichicon UFW caps for a year or two. Just bought them because I was ordering a bunch of caps and said why not. I have yet to use them. I will keep your results in mind. Let us hear the new clip if you get the chance. If you don't mind, I'd like to see your schematic once you get satisfied.... for now, LOL
:toast:

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Re: S.I.R. 100W SuperLead Schematic pt. II

Post by BRMSlash » Thu Jan 10, 2019 6:03 pm

I don't think the UFW's are as good as the UPM's when used as a cathode bypass. It doesn't appear that UFW's come in 0.68uF either. I've gone away from the Nichicon & Elna audio specific caps. They each have certain characteristics that are nice, but overall I can't get the desired overall tone. For cathode bypass duties, low impedance & large physical size seems to be the desirable attributes.

Yeah, will hopefully post a new clip over the weekend. Finally sourced the 3n3 & 4n7 X5F ceramic bright caps that I like as well (e.g. 562R10TSD33), so I'm trying them out. Also liking some Jupiter Red Astrons in the tone stack area for bit more treble grind character.

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Re: S.I.R. 100W SuperLead Schematic pt. II

Post by BRMSlash » Sat Jan 12, 2019 12:37 am

3n3 bright cap, 400v 716p presence, 3x Jupiter Red Astrons in tone stack area.

http://sclk.co/r/s88ejq

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