|
Post by jammers5 on Mar 21, 2014 20:43:05 GMT -7
A few months back I posted in here about my issue of erratic volume on my Z Wreck - the amp would surge in volume and then go whisper quiet on its own. it was suggested I change V1 and V3 preamp tubes and check to make sure the volume pot was tightly bolted to the chassis, which were done and did not fix the issue. During this testing the amp blew its 2 amp fuse, which I thought was strange, but I left it be since it had to go to a tech anyhow.
Then Dr Z sent me a new volume pot under warranty. Today I brought it in to have installed, and got another 2 amp fuse which I knew was blown. The volume pot was changed, and it was noted the replacement pot was 1 meg where the original was 500k. After it was turned on again, for a moment the volume surged again -then blew the fuse. The volume pot wiring was triple checked against the "before" photos that were taken. Everything was correct.
All components on the turret boards were visually inspected to see if there was anything obvious - nothing. My brother, (the tech) suggested there may be a different issue, as a volume pot should not blow fuses. He suggested to put the amp back to original with the 500k volume pot to eliminate any variables, so that was done. He had more 2 amp fuses so he replaced that as well, and again, it popped the fuse. Thats where he stopped.
My question is - could this possibly be a bad power amp tube? i am sure I have read on other forums of a bad power amp tube blowing fuses in guitar amps. And would a bad power amp tube have caused the erratic volume?
I really love my amp and its been sitting for several months now (my brother has been really busy with his job and I haven't seen him in a while so when he invited me over tonight I took the opportunity to bring the amp and parts) so any suggestions etc appreciated.
Should I go buy half a dozen fuses and roll a new tube thru the power section? I never even thought of bringing a spare with me tonight, but wont waste my time if it can be ruled out as a likely culprit. Being cathode biased amp am I ok just replacing one tube?
HELP!
J5
|
|
|
Post by Jaguarguy (Mike) on Mar 21, 2014 21:02:32 GMT -7
|
|
|
Post by jammers5 on Mar 21, 2014 21:07:31 GMT -7
AWESOME! Thanks!
J5
|
|
|
Post by bluzman on Mar 21, 2014 23:35:51 GMT -7
Are you using slo-blo fuses?
|
|
|
Post by DRZ on Mar 22, 2014 3:47:29 GMT -7
There are two components that are responsible for blowing fuses 95% of the time. They are Rectifiers, and Power tubes.
If your brother can't suss it out, send it in for a check up.
DR.Z
|
|
|
Post by jammers5 on Mar 22, 2014 6:06:50 GMT -7
Thanks Doc I will try the troubleshooting to narrow down which tube it is. I will post my results in a bit. Hey I may have the beast up and running again today! J5
|
|
|
Post by bourgeoisboy (Josh) on Mar 22, 2014 7:25:11 GMT -7
There are two components that are responsible for blowing fuses 95% of the time. They are Rectifiers, and Power tubes.
If your brother can't suss it out, send it in for a check up.
DR.Z So, how many Amp makers will help you out through a forum on a Saturday morning? Probably only this one ^.
|
|
floyd
Full Member
Posts: 241
|
Post by floyd on Mar 22, 2014 8:57:44 GMT -7
My RXES will do the exact same thing when it's time for power tube and rec tube change
|
|
|
Post by jammers5 on Mar 22, 2014 12:06:37 GMT -7
Problem solved! It was the rectifier tube! $15 fix!!!
Thanks everyone for chiming in and leading me to solving the issue.....and to those of you on the fence regarding a Dr Z amp look no further - I got not one, but two responses from the Doctor himself! These are special amps, made by special people!
Time to get off the computer and make some noise!
J5
|
|
|
Post by jammers5 on Mar 22, 2014 18:32:48 GMT -7
Well that was short lived!
Came down this evening to put the amp thru its paces....fuse blown again! Replace the fuse and the volume swell is back....push in on the volume pot seems to fix it until you touch the volume again. check the tightness of the volume pot, its on there snug!
now I'm frustrated!
J5
|
|
|
Post by markT on Mar 22, 2014 19:27:17 GMT -7
J5....sorry for your issues.
I'd send that amp to the Doc. (pun intended) Then you know it will be right.
|
|
|
Post by jlc on Mar 22, 2014 19:31:48 GMT -7
+1
Thorough check up, great tone, piece of mind.
|
|
floyd
Full Member
Posts: 241
|
Post by floyd on Mar 23, 2014 0:08:22 GMT -7
Change the power tubes.
|
|
|
Post by j4gitr (John) on Mar 23, 2014 3:26:40 GMT -7
|
|
|
Post by jammers5 on Mar 23, 2014 6:43:24 GMT -7
yeah im gonna get new power tubes to rule that out. I can get a matched quad of JJ's for $60 here locally - anyone ever use them in a Wreck?
|
|
|
Post by jammers5 on Mar 23, 2014 6:43:42 GMT -7
Luckily my "tube guy" is an old family friend and I can get the tubes today, so I am off to get them and try that. Should have an update in about an hour....
J5
|
|
|
Post by jammers5 on Mar 23, 2014 8:29:14 GMT -7
Nope still not fixed. Actually there is a vast improvement as the volume is not swelling on its own, but the volume pot is non responsive between 0 to 9 o'clock. Moving it causes the swells again. Frustrating.
Doc - would you supply the schematic for my brother to trouble shoot? He is a certified tech with over 30 years experience in repairing all sorts of electronics (mostly TV and radio) I trust him more than anyone else locally. The thought and cost of shipping this amp back to your shop is scary - I live on an island out in the North Atlantic and its super expensive to get things out of here. And then there is the thought of this amp getting possible damaged in transit. This would be the less stressful option for me. I am hoping you would be ok with this....
J5
|
|
|
Post by BradPaisleyFan (Pat) on Mar 23, 2014 13:06:50 GMT -7
Nope still not fixed. Actually there is a vast improvement as the volume is not swelling on its own, but the volume pot is non responsive between 0 to 9 o'clock. Moving it causes the swells again. Frustrating. Doc - would you supply the schematic for my brother to trouble shoot? He is a certified tech with over 30 years experience in repairing all sorts of electronics (mostly TV and radio) I trust him more than anyone else locally. The thought and cost of shipping this amp back to your shop is scary - I live on an island out in the North Atlantic and its super expensive to get things out of here. And then there is the thought of this amp getting possible damaged in transit. This would be the less stressful option for me. I am hoping you would be ok with this.... J5 Well that's not really an issue because it's against the Z Wreck rules to play it below 9 o'clock anyways
|
|
|
Post by jammers5 on Mar 23, 2014 16:38:04 GMT -7
Sorry if I don't laugh bradpaisleyfan - I am very frustrated that I have a very expensive amp laid up and using a Deluxe Reverb for gigs...
J5
|
|
|
Post by BradPaisleyFan (Pat) on Mar 23, 2014 17:18:20 GMT -7
Sorry if I don't laugh bradpaisleyfan - I am very frustrated that I have a very expensive amp laid up and using a Deluxe Reverb for gigs... J5 I understand your frustration...hopefully you can get it fixed and get it gigging again.
|
|
|
Post by BritInvasion on Mar 23, 2014 18:10:19 GMT -7
The fluctuating volume makes me wonder if the phase inverter tube is bad.
|
|
|
Post by DRZ on Mar 23, 2014 20:22:32 GMT -7
Hey J5 now that you have your fuse problem solved, re-install the pot I sent you. Z
|
|
|
Post by jammers5 on Mar 24, 2014 4:37:04 GMT -7
Thanks Doc will do. As previously mentioned, The replacement pot was 1 meg where the original was 500k.....will that be ok?
Also all preamp tubes were swapped with known good ones so we already previously eliminated that....
J5
|
|
|
Post by DRZ on Mar 24, 2014 5:18:28 GMT -7
|
|
|
Post by DRZ on Apr 5, 2014 8:31:16 GMT -7
WELL jammer any update? Are your frustrations a bit lessened ?
Z
|
|
|
Post by jammers5 on Apr 29, 2014 4:10:26 GMT -7
Unfortunately no Dr Z...and I apologize for not checking in here in a while. After all new tubes throughout the problem persists, but "life" has gotten in the way of any further attempts at repairs. The amp sits quiet in my studio until I can re-swap the pot. Hopefully by the beginning of May the amp will be on the bench again and I will update you then. Missing this amp like crazy and am using my backup Deluxe Reverb right now for gigs in my country band. Playing a gig with my new rock band this weekend and having to bring a Marshall amp to that....would have loved to use the Z Wreck for that gig but such is life.
I'll keep you posted and may be back to "pick your brain!"
Thanks again
jammers5
|
|
|
Post by DRZ on Apr 29, 2014 5:23:55 GMT -7
Wow what a drag. I realize it is a long shipment back here, but it will return in better then new condition and end yours and my frustration with this issue.
I did do some changes on the Volume pot , to get a better response, but if you would like a new 500K pot I would be glad to send it to you. It sure seems it needs changing even if you have other problems.
E Mail me your address again if you want a new 500K.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 29, 2014 6:17:16 GMT -7
Incredible support Doc...hope you get a resolve on your issue, jammer!
|
|
|
Post by jammers5 on Apr 29, 2014 17:46:34 GMT -7
Wow what a drag. I realize it is a long shipment back here, but it will return in better then new condition and end yours and my frustration with this issue.
I did do some changes on the Volume pot , to get a better response, but if you would like a new 500K pot I would be glad to send it to you. It sure seems it needs changing even if you have other problems.
E Mail me your address again if you want a new 500K. Hi Doc: Thanks for your responses. Tonight I went out a bought a soldering iron (I am not at all unfamiliar with soldering but my cheap radio shack one died about a year ago) and reinstalled the new volume pot. I fired her up and all is well! It appears I had two issues at play here a bad tube AND volume pot! !haven't had a chance to really put it thru the paces but the symptoms appear to be gone! So now I got fresh tubes in the beast and a gig coming up this weekend! Plus a new soldering iron to play with....time to throw some new pickups in the Strat! Thank you again for all your help Dr Z - there is no other amp for me than a Z! I am a life long customer! J5
|
|
|
Post by jammers5 on Apr 30, 2014 4:26:40 GMT -7
Update:
Put it through the paces for a half hour with no symptoms!!!!
J5
|
|