Gonna have my 300sei modified!
Nov 29, 2004 at 6:10 PM Thread Starter Post #1 of 26

tjkurita

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I'm bringing my 300sei to Tubesville on Thurs. to have it worked over. It works great and I like it, but I'd like it to be all it can be so I made an appointment at Tubesville. He's going to look at it and make recommendations for modifications.

Check out Tubesville and Noise Audio here:

Tubesville

Blackie has worked on all my tube guitar amps. He's the real deal. This is the first Hi-Fi work I'm bringing to him.

I'm curious to know what mods Bozebuttons made to his 300sei and compare to them to Blackie's recommendations.
 
Nov 29, 2004 at 8:07 PM Post #2 of 26

cortez

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I was wondering the other day about bozebutton's modded 300sei that I hear so much about here on head-fi. Does anybody know exactly what mods were done on his 300sei and who did them. I was thinking about the head amp I want to upgrade to from my upgraded mpx3 and was thinking a higher end Singlepower because I like the way the SP amps sound and like the fact that they are based on the 6sn7 tube which is a tube I have invested a lot of money into. But some other high end amps have also wetted my appetite such as the 300sei, the up coming A10, among others.

Does the 300sei have a stepped attenuater for vol control? I would be surprised if it didn't being that they cost so much.
 
Nov 29, 2004 at 8:57 PM Post #3 of 26

tjkurita

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I found a post where Boze outlined some of the mods. I think he had the standard wire replaced with silver wire. He also took out the input selector and balance knobs (had them bypassed). Most importantly, he had the the H/P setup re-wired so the signal is sent directly to the HP jack. No more HP switch or speaker terminals. He also had a stepped attenuator installed (I think). The mods were performed by the guy who sold him the amp. I think.
 
Nov 30, 2004 at 2:54 AM Post #4 of 26

bozebuttons

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Quote:

Originally Posted by tjkurita
I found a post where Boze outlined some of the mods. I think he had the standard wire replaced with silver wire. He also took out the input selector and balance knobs (had them bypassed). Most importantly, he had the the H/P setup re-wired so the signal is sent directly to the HP jack. No more HP switch or speaker terminals. He also had a stepped attenuator installed (I think). The mods were performed by the guy who sold him the amp. I think.


I added a 100k dactc2 recently to my Cary myself(came with a noble pot before) All other mods where done by the origional owner. Mods done Jensen caps where installed,solid silver wiring,Headphone relay & switch where bypassed as well as selector,& balance switch where also bypassed,only 1 input rewired direct to be a headphone amp only, no speaker ouput.Origional owner had it setup to be a speaker amp with no headphone output,He rewired it for headphone output only as per my request when I bought it.
Tubes are Sylvania VT231s & WE300bs(prefer them over TJ meshplates I had).I love this amp,it always sucks me into the music when I listen to it.
I would like to hear what Tubesville recommends.
 
Dec 3, 2004 at 6:55 PM Post #5 of 26

tjkurita

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My 300sei is going to the for sale section!

Talking to Blackie at Tubesville, I am going to sell my system and have him do a custom build for me. It will be a 6sn7 driving 300b dual-mono system with two 5u4 rectifiers. It will be a single unit, but the output will be dual mono. It will have a two layer copper chassis (!!!) with the circuit sandwiched between two layers of copper. A simple, elegant and modern aesthetic design. There will be a headphone switch.

More details to follow.

Check out a few of Blackie's builds here:

Noise Audio
 
Dec 4, 2004 at 1:25 PM Post #6 of 26

blackie

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howdy mister!

i am so excited about your build.

my brain is spinning with parts choices. here's what i came up with.

i considered a crew of my favorite transformers for outputs. i am really in love with my friend jack elliano's custom built stuff from his company, electraprint. also, i totally love lundahl's offerings from sweden. morrison, komuro and i have all used these with excellent results.

i have, however found something even more exciting.

my absolute favorite iron of all time was Tango out of japan. sadly, they closed their doors. happily, they reopened them as "Iso". sadly, the hairy price range only allows their use in the higher priced builds.

happily, i have found a VERY WORTHY substitute for the tangos. orient hi-b cores just like the tangos, awesome m-3 laminations, beautiful cases, kickass specs and affordable in our price range! a cut above!

6123HS.jpeg


as a headphone listener, i can't give you anything less, you bastard!
i ordered them already, couldn't resist haha!

after brainstorming about the absolute best i can do in your range, i have come up with the following.

full dual mono construction on a bigass single sandwich chassis of copper.

tube rectified class A single-ended 300b's driven by a 6sn7. 1st stage direct coupled (no cap) and audio note copper foil in oil cap driving the 300b. solid fine silver wiring in signal path, silver/copper/teflon wire in power supply. 3 line level inputs. headphone out with silent load switch. power supply caps are polypropylene film-in-oil beer can type like the "secret weapon" line amp you liked. cardas connectors throughout. funky-ass mega cool military chokes with sick "filter reactor" decals on 'em and flaking olive drab paint haha.

prepare for death

-blackie.
 
Dec 4, 2004 at 1:51 PM Post #7 of 26

Wodgy

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Tubesville, if you're going to literally rebuild the entire amp, changing the circuit and the output transformers, why not just build a whole new amp from scratch? It doesn't make a lot of sense to me. If you're going to replace all the parts anyway, tjkurita could sell his existing amp and put the money towards the new scratchbuilt amp.
 
Dec 4, 2004 at 6:43 PM Post #12 of 26

blackie

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a single 6sn7 will drive the 300b beautifully if you do it right. each tube contains 2 triodes. my circuit drives one with the other, direct coupled, and produces plenty of drive from one tube...with no coupling cap necessary, reducing the coupling caps in the entire circuit to one. for which we use...beauty. a handmade copper foil-in-oil.

the goal is to use as few parts as possible for the job, of the highest quality we can afford. simplicity and elegance.

-blackie.
 
Dec 5, 2004 at 3:37 AM Post #13 of 26

agile_one

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Dec 5, 2004 at 3:58 AM Post #14 of 26

blackie

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thanks mister.

i see you caught a load of my friend agatha. i'm gonna fly out to LA for xmas and stay with her for a week. gotta meet her new boyfriend and kick it with her...LOVE HER

i get so excited when get to design and build something. i get to build my dream amps. i build each one like its gonna be mine and i get even happier when i give it to my client. i try to make each build hotter than the last.

we'll post pics when its done.
 

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