trinityamps.com

Hey guys I am new to the forum and amp building as well with only a trifly under my belt so far. Build seemed to go well and the readings looked good but I have no sound. Went through it a couple of times and redid my volume and input and all the shielded cable, gave pins 5 and 6 of the output and 1 and 6 of the preamps a light tap when everything is on and there is a pop coming out of the speaker then but no sound from the guitar, any suggestions?
Here are my readings and a few pics:
Rectifier Pins: 649 VAC
Cap 2: 439 to 442 VDC
Cap1: 44 to 437 VDC (moving VRM from low to high)
Power tube heaters: 6.95 VAC
Pre Amp heaters: 6.96 VAC

Thanks

Can post all your voltages per the checklist (set your B+ as per the sheet as well)

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

Thanks Stephen will do, never had to troubleshoot before and I just read over the troubleshooting section and the manual, can someone tell me exactly what I must have the multimeter set to for each measurement (other than the readings I've shown above)so I don't make any mistakes?

Thanks

Well worst case, if you dont have autoranging, is to set it to 500V. But the voltages are on the layout so you should be able to preset it to match clsose enough. The are all DC. Isn't there a secion on how to do voltage readings as wel?

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

Well I was waiting for that missing cap my work station got away from me a little bit, hopefully I'm all set up to get this figured out now . I was missing some of the back pages of the manual but I got everything together now! Here is how things look not good:

VRM Idle seems good:
First cap 440 VDC
Across Rectifier Pins 640 VAC

With B + set to 400 VDC:
Pre Amp
R4 to Pin1 (suppose to be 203) 390 VDC
R9 to pin6 (suppose to be 191) 392 VDC

C7 33uf cap+ (suppose to be 340) 400 VDC
R15 6v6 (suppose to be 29) 0
Where R3 C3 and C4 meet (suppose to be 1.7) 0

Any suggestions?

Thanks

Check you preamp and power amp board grounds. You have no current through the power tube so no womder its not making any noise. What are the pin voltages on the cathode pins of the preamp tube? These would normally be around 1VDC range.

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

I was resoldering and forgot a couple things sorry for the misinformation seems like I'm getting more confused everytime I look at this. Here are the numbers from where everything was originally and the cathode Pins:

B+ set 393(max)
Pre amp
R4 to Pin1: 167
R9 to pin6: 159

C7 33uf cap: 316
R15 6v6: 20.4
Where r3 c3 c4 meet: 1.8
R7: 1.7

Cathode pin3: 1.8
Pin8: 1.7

All my numbers except the cathodes are a bit lower than target?

Thanks

What are the voltages at pins 3 and 4 on V2?

Pin3: 393
Pin4: 380

Just reading through the forum and getting towards the middle pages noticed a couple of people with low volume, seeing as my numbers were a bit under all around but not way out of the ballpark I fired it up and cranked everything and I do have some sound with VRM maxed and volume and gain past 9 barely noticeable at 6?

Your 6V6 is very under biased at 20v. should be closer to 29. did you get the bias resistors in correctly and switched correctly?

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

Reflow ypur power amp grpund at the board and chassis.

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

Reflowed everything associated with power ground on the board and chassis still reading 21.2. Same result as before no sound at all till 7 0'clock and then the amp sounds great but no real volume VRM is working it adjust the bit of volume that is there accordingly.

Anode and screen voltages at V2 look reasonable, but like Stephen said, the bias on V2 is low. Make sure the 6V6/6L6 switch is wired properly. If you shut the power off and remove V2 and one end of C11, you should read 750 ohms between pin 8 of V2 and ground if the switch is set for 6V6. With the switch set for 6L6 you should read about 320 ohms.

Check the values again and for fun, you might try the switch in 6L6 position and see if the bias goes up and at what plate voltage?

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

Redid everything associated with power ground and the switch, now reading 743 ohms between pin 8 of v2 and power ground 6v6 and 315ohms in 6L6. My numbers improved all around b+ is now 403 at max and r15 6v6 is now 28, my preamp numbers at r4 and r9 went from 160 to 175 replaced the 12 ax7 with a spare and those numbers improved again to target. All my numbers are up to target now and there was a noticeable improvement in the volume of the amp. No real presence until after 6 on the volume and gain and switching to my KT66 in 6L6 mode wasn't much louder. The amp sounds absolutely fantastic outside of the lack of volume, significant volume change between tweed and tude everything seems perfect outside of it not reaching the volume it should?
At max I guess it is plenty loud I just find it strange that I can't hear anything until gain and volume are past half with VRM maxed, don't know if this is a problem or not?

Good news on that front. It is pretty quiet until about half way up. This takes some by surprise, but it sounds like it is working correctly now. When you switch to the larger power tubes, you do need to switch the bias as well, did you do that with the KT66? Try a 6L6 perhaps.
I think you have done it!

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

Thanks to you and some help from Mitch as well, thank you for your patience. With a young child upstairs I never really get to turn my volume up that high and that's why I thought there was a problem originally(I did remember to flip the switch for the KT66), because I never get to turn up that high is also why I never achieved the great tone I get from this amp absolutely awesome. Thanks for all the help I'm glad it didn't work right away I learned much more because it didn't. After a little more study I'll be back for more!

Thanks guys,
Garret

Glad you got it working.

Mine is fairly quiet until about half way up, too. Also I have to have the guitar volume up pretty high for crunchy tone.