The 6550 Experience

[bill bokey]

Here's a clip of Dave's 6550 tubes (one of which has a "JH" mark on the base...)

https://soundcloud.com/castle-made-of-s ... -old-stock


The guitar is my '78 Ibanez silver series. Maple neck and some japanese wood body...pickups are Fender CS69
Pyramid Nickel Classic strings, Fender Medium plectrum.
Same guitar volume as the previous clips.

[daveweyer]

I can't wait to hear the responses! That's actually one of Jimi's tubes in there. Who knows, it might even have his DNA on the base somewhere.

[shakti]

Here's a clip of Dave's 6550 tubes (one of which has a "JH" mark on the base...)

https://soundcloud.com/castle-made-of-s ... -old-stock


The guitar is my '78 Ibanez silver series. Maple neck and some japanese wood body...pickups are Fender CS69
Pyramid Nickel Classic strings, Fender Medium plectrum.
Same guitar volume as the previous clips.

Maybe I missed it, but how do you have your guitar volume set?

Dave, did you see the photo I linked to?

Lastly, listening intently to Who Knows, I believe it is without a fuzz throughout (except the Octavio towards the end), which gives you an idea of the amount of overdrive he got. But it's those in between tones that really throw me...so clear yet watt and with snap, and sustain. Very much at his fingertips. Bill bokey's tone is sweeter than mine. Perhaps I need to remove the V2a bypass cap?

[bill bokey]

Maybe I missed it, but how do you have your guitar volume set?

It's on 5 for the last three clips I made. I didn't touch it as I wanted to hear the difference between settings.

I only have a wah and an Octavia clone so I'll see if I can get closer to his 'Who knows' tone with those two pedals.

[shakti]

On 5, really? So you obviously have a lot of overdrive in reserve. My particular guitar would be a touch muddy on 5, but that's through the Uni-vibe preamp. Again, a number of upgrades are in order on my guitar. The Highwood saddles seem to accentuate the bass a bit - the tone is firm and big, but sounds more cluttered compared to the Raw Vintage saddles I usually used. Less "elegant" for lack of a better word.

But in any case, "tampen brenner", as we say in Norwegian... I had to clear my head before going to work (on Christmas Eve, hooray!), so I got tinkering again. I de-soldered one leg of the .68uF on V2a. I also desoldered the 5n bright cap, and to my surprise discovered that it had drifted badly and measured closer to 9n! I spent a good half hour experimenting back and forth with alligator clips on a 1500pF silver mica bright cap, trying different combinations of V2a and bright channel volume bright cap. For one thing, the 9n bright cap was just way too big - it did bring in some snarl and snap that is missing without a bright cap, but it was just too unsubtle, and extended too far into the lower mids and bass, and just made everything a bit nasty and hard to control. A 1500 pF was much more usable - much smoother overdrive and not as overwhelming. With the V2a bypass cap, I was undecided - it's a little warmer without it, but it does something cool too... But altogether, I just got much closer to the goal with a smaller bright cap. A 5n may still be the ticket, but one that actually measures 5n, and not 9n...

In any case, I am edging closer and closer. In my two video clips there is just too much distortion, and in a slightly nasty way, and it doesn't clean up like it should. But I am very confident that adjusting three different factors, the last pieces of the puzzle will fall into place:
1) V1 cathode: 820R/330uF shared, or split with 820R/.68uF on bright channel?
2) Bright channel volume bright cap: 5n or smaller?
3) V2a bypass cap: none, .68uF or alternate value?

It's all about getting the right amount of overdrive, the right smoothness, clear and not muddy bass, and the right clean-up so you can get from the clean, snappy Who Knows tones to the full amp, fuzzless overdrive tones, to the right balance between warmth and gain/saturation with the fuzz engaged.

[bill bokey]

ok you're right, there is a lot of gain... too much in fact so I had a think about it all and realised I left the 'Randy Rhoads' mod in place... I didn't think it mattered as the guitar has to be plugged into channel II for the cascade thing to happen but then I also realised that there is no more 470k voltage divider to ground... hence more gain !!!

I reverted the amp back to normal and here it is :

http://soundcloud.com/castle-made-of-so ... od-removed

Same settings on the amp and the guitar as the previous clip.

[Xplorer]

Dave, thanks a lot for the explanations , and the 12at7 and caps arrived !
i'm currently working on the amp.

Thorleif, from what i experienced - but it was with another amp - a fuzz on high volume but zero fuzz, could provide these bog cleans on who knows etc ( without it, it's definitely missing something. also, "OFF", even on a non modified fuzz would still mean something since it's non true bypass - Dave also mentionned some Jimi's fuzz with the "on/off" switch being rather used as an input bias value changer ) , and if i either pick harder on the strings ( with a strat volume arround 8 or 9 ), or go from about 9 to 10 on the strat volume, it gives some much warmer and thicker tones. it could answer some things you're looking for.
oh, and the input bias pot on the fuzz is engaged just enough to let a wah working in front of it, so it's cleaning the fuzz too.
so it's like it's as clean as without fuzz at all , but there's something different in the tone and dynamics, affecting the results according to what you do on the strings.

anyway, i didn't experiment yet with such modded amp and it may be different there, so i can't tell anything.

from all the clips i've heard from you guys, i'm hearing something definitely hendrixy, in a way that we never reached before, and that's fantastic. on another hand, it's strange because it can give some half bog tone, and half .. something else but not bog. it's still missing these special throaty "low end high frequencys" , that we can hear 100% and with no effort with a 45/100, like for who knows. it's not there. it's more like a Royal Albert Hall tone. the recording and mic placement or anything else can't mimic that, it's in the amp.

can't wait to experiment with it

i don't know if it's about your speakers, or anything else.

Bill , it's got better cleans now ! cool, it's very interesting to hear clips at each step of your mods, really.

[bill bokey]

This one starts with volume on 5 then up to 8 :

http://soundcloud.com/castle-made-of-so ... ho-knows-1


It definitely works better without that silly heavy metal mod !

I'll throw in a wah and octavia later on...

[Xplorer]

Voilà ! that's what i thought, cleans with the volume on 5 max , something's wrong. 8 and still getting it now sounds more reasonable.
cool clip

[Xplorer]

Here you can find some Hendrix records that sound close to your clips, i think.
very interesting to hear what you did. i put it in the same file as the great Kazani record from Dave.
some hear my train a coming versions, and Gypsy blood.

https://drive.google.com/folderview?id= ... sp=sharing

[Tazin]

Kinda thinking out loud here:
Ok, everyone knows what the original (unmodified) circuit is for these early '69 Super Leads. Now, hypothetically, if Hendrix's '69 amps were initially unmodified then I would think that you might be able to tell by comparing the sounds from a mid April '69 bootleg to later '69 or '70 bootlegs. In addition, does anyone hear a distinct difference in Jimi's tone when comparing something from mid April 1969 to his later stuff?
I know this is a stupid question, but has anyone tried a stock '69 Super Lead circuit in order to try and capture any of the tones that Jimi had from mid April through the rest of '69? If so, then what were you hearing that led you to believe this circuit (unmodified '69 Super Lead) was not the correct one?

[Xplorer]

something that may have to come into the equation, is that maybe ... some amps were modified by some others than Dave, with different mods, on some other amps and before april 1969.

Also, the 8 superleads ordered to marshall were directly sent to Dave from what we know, so they weren't recorded stock.

a stock superlead, hearing mine, well there are some Hendrix accents for sure, but as always, it's close but not fully there.

we should do comparison clips anyway, that would be interesting, but probably in another thread, not too mix things too much and get lost in the various quests and observations.

about Bog , who knows, the évolutions of the clips and mod tweaks will maybe tell but it's maybe not impossible that the amps that Dave modded were touched again by some others ( as Dave said he had to re do some mods sometimes, finding amps which came back at west coast , if i'm correct, Dave ? ) , before the bog concert, still in the year 1969.

[bill bokey]

With wah and Octavia (Fulltone Octafuzz). Guitar on 5 at the start, then up to 10 and back down with the Octavia

https://soundcloud.com/castle-made-of-s ... ho-knows-2

But I should tweak the EQ a little, more bass actually sounds better now...

[Xplorer]

great ! much closer to bog, very different from your first clips. interesting evolution.

Merry Christmas everyone !

[Xplorer]

old clip. it's surprising how both amps ( west coast mod superlead and 45/100 ) get in the ball park.

so playing on what they have in common now ( such voltage setup, tubes .. ) looks like the way to go. + shared cathode. + .. ?
+ the right fuzz i think and the right speakers.

https://soundcloud.com/xplorer80/who-knows-noodling