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It's not good... seems to be locked on OD. pulling on of off the switch doesn't do anything... I have to let all volume to 0.1 and use the OD pot as a volume to get a clean sound...

I got a question at V4 and see my comments... might be it. If there's suposed to be something there, Ill do it and update.

Thanks

Reading:

V1 12AX7
1: 135.9
6: 118.3
8: 1.11

V2 12AX7
1: 183
3: 1.38
6: 103.7
8: 0.82

V3 12AX7
1: 286
2: 54
3: 74.4
6: 186.8
8: 1.78

V4 12AT7 (is there a bridge between pin 3 & 8... wasn't sure so I did not put on... is Pin 8 supposed to be naked? ***From completed build picture... yes it's there... but it kills my sound with a very loud noise)
1: 214
2: 74.2
3: 76.7
6: 411 WTF ? not a reading error did measure 3 times
7: 37.7
8: 87

V5 6V6 (BIAS 18.0)
3: 485
4: 458
5: -41

V6 6V6 (BIAS 17.6)
3: 485
4: 457
5: -41

Did the link between the pins... NOT GOOD... loud noise from the cab... undo the connection and it came back to normal (which is the same as the first post)

Weird... looking at picture of completed build... it is supposed to be there !?!?!?

The link is supposed to be there so if it doesnt work with it installed, there must be another issue around v4.
The OD switch must be miswired if it is on all the time. Check your switch wiring.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Ok, but if I link the 2 pin like it suppose to be linked... the amp is unusable... can't stand the noise from the cab (freaking loud and deep humming)... anyone a direction for me to look

Thanks

Well, there is an issue with the connectipn or a part around of v4 that you need to find for it to work correctly. A good picture of that area would help.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Good day here's some picture... sorry for the delay... I had someone triple check all the amps vs layout and schematic.

(Got the over drive problem solved... I had conected the wire from (V2 Pin2) to the OD jack on the same leg as the resistor...)

BUT having this made, I've try to connect the bridge (I had to use the blue wire over all the other connection...) but same result.

So it's now off again... and I can get pretty good sound out of my amp...(actually I love it... but I'm concern with not having the Bridge between pin 3 & 8 in V4)

Oh and same reading give or take 0.5 to 1 V... my 411 on V4 pin 6 is now 409 (2V is my biggest variation)

(Bought my kit in october 2016 so I have layout rev:18 & sche Rev:11)

(so my wires from from V2 to V3 are inverted... switch them and no differences they are now back as my layout rev:18)

V4 is the phase inverter that feeds signals to the power tubes. The connection between pins 3 and 8 is necessary for proper operation of the phase inverter. Put it back in place. The amp can't work at full power unless the phase inverter is working properly so both output tubes can drive the transformer.

Now that the problems around V3 and V4 are fixed, try swapping the pin 3 connections at V5 and V6 back the way they were originally.

Ok, reverse the connection at V5 and V6, done
Re-link pin 3&8 at V4...

Amp is unusable... can't even stand the noise long enough( 1-2 seconds) to take measures at test point

Undo the bridge in V4 and my amp is playable again

OK. Swap the pin 3 connections at V5 and V6 back the other way.

The amp uses negative feedback and if the phase at the output transformer is reversed, the feedback becomes positive and the amp turns into an uncontrolled oscillator.

Put the bridge back between pins 3 and 8 at V4. Pull the output tubes and measure the voltages at V4.

Yes, you must get the phase inverter sorted out.
I will post the latest layout . Check the signal path and make sure you didnt reverse any connections.

Layout



Schematic

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Wow, I have great news...
It now fixed... thanks to Mitch...and a quality kit from Stephen & his company.

The issue was that Mitch made me invert the connection on both V5 and V6 to cancel my first hum... (That was actually caused because I didn't put the bridge in V4 in the first place...but he didn't know that I had made this mistake in the first place...)

I love my Triwatt better now. The ways I can shape my sound now can't be compared from what I have in the YouTube video that I have made

Thanks again.

(I will post m'y new reading... but right off the bat... my 411 went down to 265.3 in V4 pin 6

Great news that you got your Triwatt working!

Now that you have both output tubes working it must sound a lot better.

Yes, it was a bit hard to keep track of the way you had your output tubes connected to the transformer and whether or not you had the jumper in place between pins 3 and 8 on V4. Swapping the output transformer primary connections is the standard way to clear up humming and squealing in an amp with negative feedback..... Assuming everything else is wired properly!

Are the voltages at V4 closer to what is shown on the schematic now?

All my reading are within 5% under in V1 and V2. V3,4,5,6 are over by 5 tu 10 %. This is having my bias set at 17.8 for TP1 and 18.0 for TP2.

I can't believe my ear how quite it was after I did the latest correction. I thought I killed it because I didn't have any kind of noise in my cab... but once I turned both MV and Nv (I was connected to the normal channel) it came alive.

I'm going to read a bit more on the EL34 mod since I was wondering if I put my 6L6WGB just for crap and giggles how the Triwatt would react. In the building instructions p.59 they say to flip the bias switch to KT66, replace the 620K for a 1M, (the one under the 15K and the 47 K ... on the bottom right of the board) since my old Genz Benz el diablo 60 could take 6L6 or EL34... I might just give it a shot if I can get confirmation that I can't really kill the amp for a 10 min trials

Excellent news. Thanks mitch m .
You can do EL34s, but you need to have some experience in setting the range resistor. The recommended value should work but you need to be very careful when you do it and also how you mismatch the OT setting to the speaker cabinet.
My suggestion is toe enjoy the 6v6 for a while first!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Ok, I play on it for 3hrs straight... reading after...

Still impress how quite it is...and how loud it can get when you drive in your strings...

Never my guitar volume pot had so much influence on my tone... just wow. (and I still can't believe that I made it from bits & pieces)

Read: MINE / TP LAYOUT / VARIATION / VARIATION IN %
V1: 12AX7
1. 137 / 150 /-13V / -8.667%
3. 1.37 / 1.2 /+0.17V / +14.167%
6. 119.9 / 120 / -0.1V / -0.083%
8. 1.07 / 1 / +0.07V / +7%

V2: 12AX7
1. 196 / 179 / +17V / +9.497%
3. 1.33 / 1.2 / +0.13V / +10.833%
6. 104.4 / 106 / -1.6V / -1.509%
8. 0.79 / 0.7 / +0.09V / +12.857%

V3: 12AX7
1. 308 / 269 / +39V / +14.498%
2. 53.5 / 67 / -13.5V / -20.149%
3. 73.3 / 71 / +2.3V / +3.239%
6. 191 / 188 / +3V / +1.596%
8. 1.72 / 1.5 / +0.22 / +14.667%

V4: 12AT7
1. 313 / 274 / +39V / +14.234%
2. 73.2 / 71 / +2.2V / +3.099%
3. 78.5 / 74 / +4.5V / +6.081%
6. 296 / 236 / +60V / +25.424%
7. 37 / 64 / -27V / -42.188%
8. 78.6 / 74 / +4.6V / +6.216%

V5: 6V6 BIAS(18)
3. 475 / 441 / +34V / +7.710%
4. 448 / 411 / +37V / +9.002%
5. -40.3 / -39 / -1.3V / +3.333%

V6: 6V6 BIAS(17.2)
3. 483 / 441 / +42V / +9.524%
4. 452 / 411 / +41V / +9.975%
5. -40.4 / -39 / -1.4V / +3.590%

I'm not even going to bother trying anything else for a long time... just finish a 3hrs session on it... and I can't find word strong enough to express my gratitude to your son... for driving you crazy enough for you to start building amps!!!

Thanks again

Steph

Thanks Steph. I'll tell him!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

How about trying the KT66 option. Lot's of great British tone there.

I'm so stoked to see another happy Triwatt player!

_________________
Great tones come in small glass jars!

Zaphod, you are so right. Great tone in those big bottles!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps