Hi All,
I have started a new build and figured I would post up some pictures. I decided to build an amp similar to the Z-Wreck.
As I am not too good at drilling sheetmetal manually and having it look at all presentable, I decided to have some sheetmetal fabricated by my shop folks for this.
I am using Heyboer power and output Iron, with a hammond 159Q choke. Power tranny has 250V and 280V taps. Output tranny is the rocket A470 type.
I am trying to keep this similar to the original, so I am going with Saratov 6P14P-EV output tubes that I picked up from Terry Killgore.
The balance of the tubes will probably be NOS EI and Tungsram 12AX7s and an NOS RCA 5AR4, manufactured by Mullard at Blackburn. These are a slight deviation from the original, but I figured that couldn't hurt.
I have started assembling, so here are a few pictures:
So I got the amp fired up this evening.
I am seeing red plating on one of the power tubes. As an experiment, I swapped the culprit tubes position with another in the quad, and had red plating in the same socket.
So, I don;t believe this is a tube related issue.
Tubes are saratov 6p14p-EV from Terry Kilgore.
Voltages are:
B+: 268
Screen: 266
I am measuring approximately 250 volts on the plates of the 2 parallel tubes on one side of the output transformer. This is the side with the red plating tube.
I measure 268 on the plates of the other 2 output tubes.
Any suggestions on where to begin my troubleshooting?.
Nice work. Have you checked that socket out? Check continuity all the way around and see if a bead of solder made it somewhere it's not supposed to. It might be unlikely, but it is telling that tubes that go in that socket redplate. Occam's Razor...
Think I got the problem squared away. I had a flaky connection on the grid of the culprit socket. I also touched up the plate connection as well. No more red plating. This also seemed to square away a but of hum that I heard on initial power up.
As it is late, I can't crank it up to listen to it, but I have all expectations that it will rock. I tried it to start using my cab for my ODS, which is loaded with 2 G12-65H.
I plan to use this with a pair of Weber Alnicos: A silver bell 30 that I already have and a 50W Blue dog that is on the way.
I currently have tungsram ECC83s in V1 and V2 and an NOS EI in V3. Power tubes are saratovs and the rectifier is an RCA branded Mullard 5AR4
Nice Steve,Your lettering on the front and back,How did you do that.Also the chassis is aluminum and is it powdercoated?Looks very pro!How do you like the sound.Would you say Its like a rocket somewhat?Looking GOOD BROTHER,Mikey
Look at the Rocket voltage charts for expected voltages and if your preamp tubes are really high then you can adjust the dropping string to get the voltages down.
This may need to be done simply by watching how each leg was dropped and change the connecting points or may need to increase the dropping resistors.
Also running the 250v verses 280v can save on the power tubes and reduce total voltage. I am running 250v and 280v switched HT.
Nice job Steve.
You sure have some building chops.
It's on par with Marks.
Now I know were I can find some subcontractor amp builders.
BTW I'm curious, minus your labor how much do you have invested in parts to build that amp?
Also I can see your going to have a problem with your Switchcraft #12 input jack, the alignment of the shorting leg is a failure waiting to happen.
I was forced to stop using the #12's do to high failures and switched to the # 113, FWI.
DR.Z wrote:Nice job Steve.
You sure have some building chops.
It's on par with Marks.
Now I know were I can find some subcontractor amp builders.
BTW I'm curious, minus your labor how much do you have invested in parts to build that amp?
Also I can see your going to have a problem with your Switchcraft #12 input jack, the alignment of the shorting leg is a failure waiting to happen.
I was forced to stop using the #12's do to high failures and switched to the # 113, FWI.
DR.Z
Dr. Z
I just want to say that I think it's really cool that you post here and are supportive of the amateur builders.
I haven't build anything based on your amps, but from my experience with a few other builds the parts are often reasonable as in I could buy a used for about that much (except the collectable amp of course). As you know, many of us here build amps that we couldn't buy or as in the case with wrecks and Dumbles couldn't afford to be in the same room with.
What gets expensive is shipping and the endless hours trying to figure out what parts to buy!
Thanks for your positive contributions, I wish you all the best.
I just went through my purchase slips and for my complete amp chassis, front/back plates, cabinet, transformers, components, wire, hardware and misc. I spent $675.88 total build cost. Labor too high a cost to total but I had fun building it.
Your amps are fantastic and you provide them to your customers at an unbelievable low price.
But with my salary and family needs along with my lust for amps I could only afford to buy your Stangray with 212 blues cabinet and had to stop with that and build my own.
I just went through my purchase slips and for my complete amp chassis, front/back plates, cabinet, transformers, components, wire, hardware and misc. I spent $675.88 total build cost. Labor too high a cost to total but I had fun building it.
Ok guys here's a little insight in owning an amp company, at least the way I do it, YMMV.
Mark your parts cost is very close to mine, I shave a small amount from that, but the Z-wreck has it's own dedicated componants that are not shared with the rest of the line so costs are higher then other Z-Amps.
Lets say:
675.88 for parts cost
390.00 for labor;assembly , QA, Cab completetion, play test QA, and
boxing/shipping, appox 15 hrs @$26.00/hr
1065.88 total cost of assembly
x2.5 % mark up for list price quote
2664.70 List price for Standard color Z-Wreck head ( rounded up to
$2699.00 )
Now I wholesale my amps and do not sell direct, and 2.5 % covers my overhead and a small profit per unit. So to stay healthy and in business
I need to ship at least 8 Z-Amps / day, which we do .
That's an interesting breakdown Mike, thanks for the insight! I think a lot of people have no clue about the extra costs of owning and operating a business outside of just making your product. I still haven't had a chance to fire up a Z-Wreck, I can't wait to try one.
TAG members should stop making these amps so you can keep your Zwreck line growing even more.
I will make the commitment right now that I will stop promoting the cloning of your Zwreck since it is a production amp and your bread/butter were talking about.
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