New Express build

[xtian]

What's the deal with the "flying" components off the V1 pins? Are those extra caps required for the VVR? Those caps are heavy, and any vibration of the chassis (like, moving it from place to place) will slowly weaken those leads.

Here is a first-time start-up guide that walks you through safely firing up a new amp: http://www.paulrubyamps.com/info.html#FirstPowerUp

[Richie]

What's the deal with the "flying" components off the V1 pins? Are those extra caps required for the VVR? Those caps are heavy, and any vibration of the chassis (like, moving it from place to place) will slowly weaken those leads.

Here is a first-time start-up guide that walks you through safely firing up a new amp: http://www.paulrubyamps.com/info.html#FirstPowerUp

You can use a small terminal lug mounted to the socket bolts to add support for those parts.

Nice looking build.

[Colossal]

What's the deal with the "flying" components off the V1 pins? Are those extra caps required for the VVR? Those caps are heavy, and any vibration of the chassis (like, moving it from place to place) will slowly weaken those leads.

Those caps and pull down resistors are needed for the VVR.

[andresound]

Yip Xtian,
Cap arrangement is because of VVR. The caps are Mallory.1uf. Because of stiffness of the "large" cap legs, seems that they are not going anywhere!
Thanks for the observations guys. Any glaring mistakes noticed would be helpful iof pointed out.

[andresound]

Ok,
Amp basically done and about to test voltages etc. So now working on head cab. Cherry wood with "lazer engraved" faceplate.

Ready for finishing!!

[IMG:768:1024]http://i48.photobucket.com/albums/f214/ ... ccd031.jpg[/img]
[IMG768]http://i48.photobucket.com/albums/f214/ ... b86aef.jpg[/img]

will keep the posts coming

[RJ Guitars]

Hey Andre,

Great looking work! Sorry i have not been interactive in this thread until now, I've been doing a ton of prep and recovery work for and from the Tempe Guitar Show... great weekend and connected with lots of folks interested in DIY amp building.

RJ, heard some of the turret board material could be conductive!!! Hoping its not the case here. Any thoughts on this?

Funny thing to hear randomly... I got this report back when it happened. It involved one particular board and never showed up again and it's hard to say what really happened? I kept a few samples from the same lot and subsequent testing continues to show nothing detectable in the way of leakage... I haven't pressed the issue because it seems like it might stir a squabble and that never makes life better for anybody. I'm okay to call it a one time anomaly and let it go. Oddly enough, some of the absolute best sounding Wreck clones I've helped put together used these boards and you couldn't take them from the owners without being well armed. Maybe they are actually magic? For your piece of mind - that was a couple generations back and that board stock hasn't been available for some time. Keep building and posting, it's great to see another awesome Wreck build down there in the cape.

rj

[andresound]

Rj,
Thank you for the update and kind words! . I have a "feeling" this build is going to sound and look awsome!!

BTW guys, (and I hope I dont start a riot!!), what is the consensus with regard to PIO signal caps in these amps. The general theme on tone for these amps is "bright". Everyone is trying to find speakers (old pre-rola series for eg), to tame the bite or "ice pick" syndrome. I am of the opinion that PIO (good quality ones), are exreemly transparent, while still sounding "relaxed". Wich might be a good thing.

I was thinking of replacing the first cap (in series with the input), with an OLD PIO (.1uf), from an original one of a kind JAPANESE TEAC pro reel to reel machine (tube). Surely this cap has an effect on the tone of this amp.

Obviously, I will not preform this surgery until the amp is well broken in and played. If amp sounds awsome, I wont tuch it.

Just mt 2c worth.

[andresound]

just got this message from my tube suplier.

Dear Andre,

The pair Philips EL34 valves matched very near each other regarding the Ia and Gm figures

For 100% according to AVO valve manual: Ia = 75mA and Gm = 11

V1: Ia = 86mA and Gm = 11.4
Etched markings:
xf2
BOL4

V2: Ia = 87mA and Gm = 11.8
Etched markings:
xf2
BOL4

Really getting exited now. No excuses for a bad sounding build. Best components, tubes and advice from all at TAG

[andresound]

Ok guys,

THE MOMENT OF TRUTH. Fired up the amp today and checked all voltages and only needed to change the bias resister to get within the "range". Went to a 52k. Amp sounds FUCKING AWESOME!!! (please excuse the french). I am absolutely ecstatic

With ALL controls FULLY dimed, only some hiss . NO hum . Time to put in the NOS FX2 tubes, rebias and start tube rolling. At the moment I have a NOS Telefunken smooth plate in v3, Sylania in v2 and a chinese 12AX7WA (was the quietist one I had to hand) in v1.

Cant wait for this thing to start "opening up". (Sorry, her name is "Caryn")

Here is how the cab is coming along after 3 coats of oil

[IMG768]http://i48.photobucket.com/albums/f214/ ... 226fff.jpg[/img]

[IMG768]http://i48.photobucket.com/albums/f214/ ... 57cc7a.jpg[/img]

[IMG768]http://i48.photobucket.com/albums/f214/ ... e396eb.jpg[/img]
Getting there!

[RJ Guitars]

Ok guys,

THE MOMENT OF TRUTH..... Amp sounds !@#$%^& AWESOME!!! ...With ALL controls FULLY dimed, only some hiss . NO hum:

Are you kiddin' me??? first build and you got awesome and no hum, wait until you get her dialed in with tubes and then she starts breaking in.

Great job! Thanks for sharing the journey. You add a couple of data points for us concerning can caps and MM transformers. Can't wait to see the final product in the cab and ready to rock. Looking forward to your sound test reports!

[andresound]

Rj,
Thank you for the update and kind words! . I have a "feeling" this build is going to sound and look awsome!!

BTW guys, (and I hope I dont start a riot!!), what is the consensus with regard to PIO signal caps in these amps. The general theme on tone for these amps is "bright". Everyone is trying to find speakers (old pre-rola series for eg), to tame the bite or "ice pick" syndrome. I am of the opinion that PIO (good quality ones), are exreemly transparent, while still sounding "relaxed". Wich might be a good thing.

I was thinking of replacing the first cap (in series with the input), with an OLD PIO (.1uf), from an original one of a kind JAPANESE TEAC pro reel to reel machine (tube). Surely this cap has an effect on the tone of this amp.


Obviously, I will not preform this surgery until the amp is well broken in and played. If amp sounds awsome, I wont tuch it.

Just mt 2c worth.

Well,
If this amp is THIS quiet FULLY DIMED (and without base plate!), I amp NOT changing any caps, especially if there is obviously going to be some improvement with break in and tube rolling.
Looking forward to it.

PS Thanks again to ALL at TAG, especiaaly rj!

[geetarpicker]

It should be about a little less noisy than a fully dimed 4 input lead spec Marshall IF you back the TW down to similar gain levels probably about 1/2 with the knobs depending on pot taper. If it is indeed really really quiet dimed, I'd actually suspect it is actually oscillating above the range of hearing. One way to tell is if you fully dime it in a dim room the blue glow from the output tubes should not be any brighter than idling with the volume off. Another way to confirm no ultrasonic oscillations is to fully dime the amp, but plug in a guitar and just barely turn up the guitar volume. You should get nice crystal clear cleans. That said if there are any ultrasonic oscillations going on (above audible range) the guitar will not sound clean no matter how low you back off the guitar volume knob. Another check for this is to turn up the amp volume slowly, if the noise gets louder but then towards full volume the amp actually gets quieter you have oscillation problems.

Not trying to ruin your day, but like I mentioned these amps are fairly quiet considering their gain, but you will still hear some hiss for sure and quite a bit with the amp dimed and the tone knobs up.

[shaunf]

Hey guys, long time!

It was me who gave Andre a hand doing the final checks and completing the startup procedure.

Andre did a great job of wiring it up and the amp is very well behaved. As mentioned, it is possible to fully dime all controls and it behaves. There is plenty of hiss at this level, but no more than my '69 4 hole Marshall, and very much the same as my Express clone. There is no hum and also no squealing or any sign of oscillation. It sounds great at all volumes.

With the controls at around 12, VVR set to max volume, the amp produces crystal clear cleans playing with my 59RI LP, with volume and tone controls on the guitar backed down to around 3.

The amp is slightly darker sounding than mine, something that I put down possibly to the preamp tubes, as well as possibly the fact that the plate voltage on the power tubes is quite a lot lower than in my amp (371v, vs 408v on the power tubes in my amp). I also realized that when I plugged into my amp to play after Andre left that my amp is noticeably louder. The MM PT only has 120/240v primaries, and my wall voltage was in the mid 220's. My amp is running the Heyboers and I used the 230v primary taps when I wired it up.

I'm also running the alternate bright switch wiring, while Andre opted to go with the Ingrid wiring. I didn't really notice much difference in the way the bright switches operate between the two.

All in all a wonderful amp Andre can be proud of and I'm looking forward to seeing the completed product as well as hearing it after some tube rolling reveals its optimal setup.

[geetarpicker]

Sounds like it's healthy!

[Zippy]

If it is indeed really really quiet dimed, I'd actually suspect it is actually oscillating above the range of hearing. One way to tell is if you fully dime it in a dim room the blue glow from the output tubes should not be any brighter than idling with the volume off. Another way to confirm no ultrasonic oscillations is to fully dime the amp, but plug in a guitar and just barely turn up the guitar volume. You should get nice crystal clear cleans. That said if there are any ultrasonic oscillations going on (above audible range) the guitar will not sound clean no matter how low you back off the guitar volume knob. Another check for this is to turn up the amp volume slowly, if the noise gets louder but then towards full volume the amp actually gets quieter you have oscillation problems.

I REALLY like the way you laid that out, Glen. It all makes perfect sense in 20-20 hindsight, but I've never done that. Excellent post!

Thank you for that.