Modifications to run e80cc/12bh7a/5687 for Crack+Speedball

[JamieMcC]

Yes a picture is worth a thousand words. Nice job by the way you have implemented the changes much neater than I could have done.

[Snarii]

Hi
to help those like me who need to see the schematic of the 7119/5687 mod, I've made this based on the excellent kscwuzhere work, Kudos to him !! 

I have not kept the center lug of the 9 pin socket wired, as I was not quite sure it still made sense. The wire was taken directly from terminal 3. Could someone enlighten me on this ?
[EDIT]I've finally retained this central pin to simplify the soldering. It may have a shielding effect too.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.4shared.com%2Fdownload%2F2XQN8tW1ce%2F7119_wiring.jpg%3Flgfp%3D3000&hash=117d962bc18c08e83cec2132f18b3ae85a060b69)

[kscwuzhere]

Hi
to help those like me who need to see the schematic of the 7119/5687 mod, I've made this based on the excellent kscwuzhere work, Kudos to him !! 

I have not keeped the center lug of the 9 pin socket wired, as I was not quite sure it still made sense. The wire was taken directly from terminal 3. Could someone enlighten me on this ?

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.4shared.com%2Fdownload%2FtfFupbJkce%2F7119_wiring.jpg%3Flgfp%3D3000&hash=c2e0b937c5940ef505350d19334f300b2167e6c7)

Thank you snarri! That's absolutely perfect!!

Only reason I did t take the cable directly from terminal 3. Was because I thought the center lug of the 9 pin socket needed to be grounded. I just added a cable from the center to the dpdt. My guess is that your technique should work!!

Also gotta thank onelivewire (we brained this together) and pb for being an amazing guide!

[Strikkflypilot]

My simple E80CC/ 12AU7 switching mod. (One for each small SB PCB of course)
Even these small dip switches are more than within spec requirements.
Uses the already available PCB wiring.

Thanks to Caucasian, Jamie and the rest of You for great advice.

[i luvmusic 2]

Terminal 1: 60V
Terminal 5: 61V

YES !
believe it or not but most of my 6SN7s have similar soundstage on Crack to E80CC Amperex..love it ,this grey skirt VT-231 sounds very good
I'm very glad I can use both

  This is what i want to do with my CRACK run 6/12SN7's with it but first run it stock to be familiar with the stock sound then MODDING Time.I will need more INFO on these MOD later.Thanks!

[Strikkflypilot]

My simple E80CC/ 12AU7 switching mod. (One for each small SB PCB of course)
Even these small dip switches are more than within spec requirements.
Uses the already available PCB wiring.

Thanks to Caucasian, Jamie and the rest of You for great advice.

With parallell and 12AU7 I get 72v on terminal and 76 on term 5
In off position with E80CC I get 105v and 107 v (470ohm 0,125 w)
Is this acceptable? Or even understandable?

[kscwuzhere]

With parallell and 12AU7 I get 72v on terminal and 76 on term 5
In off position with E80CC I get 105v and 107 v (470ohm 0,125 w)
Is this acceptable? Or even understandable?

So your values for the 12AU7 are fine but the e80cc ones are on the high side. Try messing around with different resistors (I bought a pack of resistors ranging from 10ohm - 900ohm) using alligator clips and test the voltage at T1 and T5. Not every tube performs exactly the same for example my buddy's Sylvania 12bh7a needed 91ohms to run at 75V and my RCA 12bh7a needed 140ohm to run at 75V; same tube variety, different resistance requirement. I'd say anything from 60-85V is on the safe side!

[Snarii]

OK, finally here we are 

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.4shared.com%2Fdownload%2F3SMRnnbkce%2FCrack-1.jpg%3Flgfp%3D3000&hash=21f667fe585dd04f217440ebdbdad0ebd6cc775e)
After hours of surgical operations, dealing with really tiny crowded spaces where binocular vision is sometime impossible, making desoldering or soldering a challenge, broken short stock 22AWG PTFE wires, everything is now in place and my crack has achieved its ultimate mutation on the input section :

- half-DPDT with a 330R in parallel of the stock 237R still in place to achieve the 138R needed for my 12BH7A (82V). I don't have E80CC, so no need for another resistor combination. Chances are good I won't have to change anything for the 7119 as it happened for kscwuzhere.
- 2 x DPDT switches for the Standard / 7119 configuration. The wiring with the leds (HLMP-6000 / HLMP-CB1A-XY0DD) is made according the drawing I posted a few posts upward. I finally kept the central pin of the socket wired to the ground and restarted from there to the switch. I modified the drawing accordingly.
- 2 x MJE5731A to replace the MJE350. These parts are incredibly hard to find right now, nowhere in stock in the major companies with months of wait, don't know why. I finally ordered on ebay to someone having motorola parts with short pins (new ?). Whatever, they work as intended (reverse from MJE350 !)
- In front on the right, the Valab 23 stepped attenuator 100k. Behind are the capacitors I'll describe in the capacitor porn thread http://bottlehead.com/smf/index.php/topic,4744.90.html.

Modifying the crack during the initial assembly would have been so much easier ! I've replaced the wires I needed to change with 20 or 22AWG PTFE, for a neater result, the overall diameter being smaller than with PVC. Everything eventually at risk has been isolated with shrink tube.

I now just have to wait for my 7119 PQ in transit…

[kscwuzhere]

OK, finally here we are 

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.4shared.com%2Fdownload%2F3SMRnnbkce%2FCrack-1.jpg%3Flgfp%3D3000&hash=21f667fe585dd04f217440ebdbdad0ebd6cc775e)
After hours of surgical operations, dealing with really tiny crowded spaces where binocular vision is sometime impossible, making desoldering or soldering a challenge, broken short stock 22AWG PTFE wires, everything is now in place and my crack has achieved its ultimate mutation on the input section :

- half-DPDT with a 330R in parallel of the stock 237R still in place to achieve the 138R needed for my 12BH7A (82V). I don't have E80CC, so no need for another resistor combination. Chances are good I won't have to change anything for the 7119 as it happened for kscwuzhere.
- 2 x DPDT switches for the Standard / 7119 configuration. The wiring with the leds (HLMP-6000 / HLMP-CB1A-XY0DD) is made according the drawing I posted a few posts upward. I finally kept the central pin of the socket wired to the ground and restarted from there to the switch. I modified the drawing accordingly.
- 2 x MJE5731A to replace the MJE350. These parts are incredibly hard to find right now, nowhere in stock in the major companies with months of wait, don't know why. I finally ordered on ebay to someone having motorola parts with short pins (new ?). Whatever, they work as intended (reverse from MJE350 !)
- In front on the right, the Valab 23 stepped attenuator 100k. Behind are the capacitors I'll describe in the capacitor porn thread http://bottlehead.com/smf/index.php/topic,4744.90.html.

Modifying the crack during the initial assembly would have been so much easier ! I've replaced the wires I needed to change with 20 or 22AWG PTFE, for a neater result, the overall diameter being smaller than with PVC. Everything eventually at risk has been isolated with shrink tube.

I now just have to wait for my 7119 PQ in transit…

Absolutely beautiful implementation Snarii! Now just for those 7119's.......

[Strikkflypilot]

So your values for the 12AU7 are fine but the e80cc ones are on the high side. Try messing around with different resistors (I bought a pack of resistors ranging from 10ohm - 900ohm) using alligator clips and test the voltage at T1 and T5. Not every tube performs exactly the same for example my buddy's Sylvania 12bh7a needed 91ohms to run at 75V and my RCA 12bh7a needed 140ohm to run at 75V; same tube variety, different resistance requirement. I'd say anything from 60-85V is on the safe side!

Thank You and it is a good point. I only did this mod because it made sense. 470 in parallell makes 235 ohms and the switch would be easy and small. I am sure I will find something.

[kscwuzhere]

Thank You and it is a good point. I only did this mod because it made sense. 470 in parallell makes 235 ohms and the switch would be easy and small. I am sure I will find something.

It's all about trial and error. Try using a 500, 550, or a 600ohm resistors for the e80cc position!

[Strikkflypilot]

Or how about installing a self bias circuit?

[Snarii]

Hi all,

my two 7119 PQ (yes, I like to always keep some spare)  arrived this morning. Very good shape, like new indeed. They were made in Heerlen in 1966. One last visual wiring check, we're never too sure, and power. A few seconds then the 2 two blue leds light up, then the small speedbal cards, OK !

Time to check the plates. As expected, the 138ohm (= 237 // 330) 12BH7A resistor mod worked for the 7119, as I get 77.3V on the plate of the 2 triodes. Now let's get the tube the time to cool down, then put a 6H13C on its slot, and lets play some jazz….

Woww !! Stunning !

Absolutely no regrets spending some time integrating the 5687/7119 mod !

We are really one step beyond every progresses I've made so far installing all these gears. Transparency, liveliness of the music, improved soundstage, presence and focus of placement of the instruments, sensation of space, … what to say more, this 7119 tube is killer and pairs beautifully with the HD650. The 12BH7A was my favorite, but it never went this far, even properly driven by a good plate voltage.

3 months after my complete DIY beginning on the crack, I think my tuning journey has now ended, thanks to all at Bottlehead for this wonderfull amp, and those of you on the forum making me try something else, now time to enjoy the music !

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.4shared.com%2Fdownload%2F_ivNbdkNce%2FCrack-7119.jpg%3Flgfp%3D3000&hash=98be522cf91b279a7cfb8987f66fd32b7d0b4ce7)

[kscwuzhere]

Hi all,

my two 7119 PQ (yes, I like to always keep some spare)  arrived this morning. Very good shape, like new indeed. They were made in Heerlen in 1966. One last visual wiring check, we're never too sure, and power. A few seconds then the 2 two blue leds light up, then the small speedbal cards, OK !

Time to check the plates. As expected, the 138ohm (= 237 // 330) 12BH7A resistor mod worked for the 7119, as I get 77.3V on the plate of the 2 triodes. Now let's get the tube the time to cool down, then put a 6H13C on its slot, and lets play some jazz….

Woww !! Stunning !

Absolutely no regrets spending some time integrating the 5687/7119 mod !

We are really one step beyond every progresses I've made so far installing all these gears. Transparency, liveliness of the music, improved soundstage, presence and focus of placement of the instruments, sensation of space, … what to say more, this 7119 tube is killer and pairs beautifully with the HD650. The 12BH7A was my favorite, but it never went this far, even properly driven by a good plate voltage.

3 months after my complete DIY beginning on the crack, I think my tuning journey has now ended, thanks to all at Bottlehead for this wonderfull amp, and those of you on the forum making me try something else, now time to enjoy the music !

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.4shared.com%2Fdownload%2F_ivNbdkNce%2FCrack-7119.jpg%3Flgfp%3D3000&hash=98be522cf91b279a7cfb8987f66fd32b7d0b4ce7)

Absolutely beautiful build! After I installed the 7119 for my hd650s I felt the same way! I felt like I maxed out the hd650s potential and that's why I decided to upgrade to the hd800s haha! My journey has begun all over again.

[Strikkflypilot]

It's all about trial and error. Try using a 500, 550, or a 600ohm resistors for the e80cc position!

So its not just something wrong with my E80CC?