1. Win a Broadcaster or one of 3 Teles! The annual Supporting Member Giveaway is on. To enter Click Here. To see all the prizes and full details Click Here. To view the thread about the giveaway Click Here.

Thinking in building a tweed amp - 1st timer

Discussion in 'Shock Brother's DIY Amps' started by tube.tone, Jul 23, 2009.

  1. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    That's great romans, I already have ordered the book. That would be the first step. As far as for the kit, I think I'll go with Mojo's, I have purchased from them before and tejy very responsive to emails. Other option was Mission but they are a bit over my budget in third is Weber, it's impossible not consider them due to value but I have no answers to my inquiries in regard to parts specs.

    Changing subject. Can you guys explain me how the 5e3 volume controls works. It doesn't seem to work as master and volume control, correct? Will I be able to dial some nice overdriven tones without cranking the amp?
     
  2. sjhusting

    sjhusting Tele-Afflicted

    Posts:
    1,488
    Joined:
    Jul 8, 2003
    Location:
    Germany
    No. The 5C3 preamp is grid-biased, not cathode-biased. I don't have the schematic in front of me, but I believe it also uses a different phase inverter. Paraphrase instead of cathodyne, maybe?

    I'm not convinced this is worth the trouble in a cathode-biased power amp, unless you are planning on using other tube types in it, which I assume you aren't.

    Chassis should be fully drilled.

    In my opinion you shouldn't get hung up on this stuff yet. Orange drops, Mallories, Roederstein, Xicons - they are all good. Sozos and PIOs will run into lots of money for caps, and if this is a stage amp, no one will hear any difference. Including you (on stage) probably. (flame-retardant suit on).

    Can't go wrong with Weber.

    all just my ho

    steven
     
  3. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    Thanks a lot for the feedback! I'm the placing the order phase haha!

    .... Unfinished or lacquered tweed?

    Functional lacquered adds better protection, but how about aesthetically? What was the original finish?
     
  4. scottb1966

    scottb1966 TDPRI Member

    Age:
    55
    Posts:
    91
    Joined:
    Feb 8, 2009
    Location:
    Glasgow Ky
    I have built a Mission and it doesn't have step by step instructions. It has a lot of pictures and personal help from Bruce if you need it, but not step by step instructions. That said, I had not built an amp before and figured it out with a little help, so anybody should be able to also.
     
  5. Ricky D.

    Ricky D. Doctor of Teleocity

    Age:
    70
    Posts:
    11,148
    Joined:
    Oct 22, 2006
    Location:
    Marion, VA
    Weber used to recommend the 12A125A (light dope) for the 5E3. I got an alnico Sig12 instead, works well.

    Mission could probably do the export transformer. Talk to Bruce there.

    I built a Mission kit a few years ago and am 100% satisfied.
     
  6. jitensha

    jitensha Tele-Holic

    Posts:
    932
    Joined:
    Mar 10, 2007
    Location:
    Tokyo/Montreal
    I'm just finishing up a 18 watt Marshall clone form Trinity Amps in Toronto and it's been a pretty good experience. I think they also have a tweed deluxe kit. I'm just waiting on a speaker now. In addition to all the parts, the kit came with booklet which outlined basic tube amp theory, building instructions, a schematic, and a layout diagram which made putting it together pretty straight ahead. It's also got a section on troubleshooting and mods. I'll post some pics and stuff when I get it done on the home brew thread.

    +1 on the Dave Hunter book, that was also a gold mine of info for someone like myself who wanted to build an amp but knew next to nothing about them. Plus there is this forum and a couple of others where people have been extremely generous with their knowledge and support. I'd say just dive in.
     
  7. stevedenver

    stevedenver Tele-Afflicted

    Posts:
    1,474
    Joined:
    Jul 31, 2003
    Location:
    the mile high city
    me too
    i did it-worked first time

    got a weber blue speaker for it

    amazing amp

    its an easy build-basically paint by number
    you will need to have a well lighted work area and be able to work without interuption-so you can concentrate

    you must know how to solder

    youll need to make sure you use the right components -ie color banding on resistors etc-other than that double checking what you are doing-its pretty easy

    it sounds more scary than it is-

    go for it

    i highly recommend mission-i prefered the sound of mine with the weber blue over a vic that i compared side by side

    top quality amp

    and yes bruce will help you

    his kit provides nice tubes where you most need them

    you can upgrade the power tranny to a mercury too

    the 5e3 is a very useable yet portable amp-imho the 12" has it over just about everything-the cab size and quality of material also makes an important difference- ithink a 5e3 and tele is a perfect pairing

    sometimes you hust have to jump in and give it a go...youll be rewarded
     
  8. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    Update, The kit is on its way. I have decided in placing to orders. I got the kit from weber ($500) with an 12a1250 speaker and I have placed a separated order for capacitors (TAD, orange drops, mica), resistors (carbon comp, metal oxide for power) and potentiometers (CTS) at mojo.

    The only thing out of the original values is .047uf instead of the .1uf coupling capacitors.

    So far I have compiled a considerable amount of info to help me out with the task.

    Thanks for the for all the info input
     
  9. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    Question, in regard to the .1uf coupling capacitors, we have four on the 5e3correct?

    When people change the value of these caps to .047uf or even .022uf to tame bass they change all .01uf caps? Whats the criteria?

    Should I keep original values?

    Thanks
     
    Last edited: Aug 1, 2009
  10. JohnnyCrash

    JohnnyCrash Doctor of Teleocity

    Posts:
    11,120
    Joined:
    Mar 12, 2005
    Location:
    Fullerton, CA
    I'd leave them all stock 0.1uF for now. After a few weeks you might consider what many tinkerers end up doing: changing only the one coupler from 0.1uF to 0.022uF, the one at the Bright channel's plate.

    Even '60s BF Fenders have the large 0.1uF at the phase inverter which is fine since the caps are smaller at previous stages in the preamp. The same approach can be had with a 5E3 (even with the different PI circuit).

    Some folks use the Bright channel for humbuckers and the Normal for single coils - as such, they leave the caps as-is except for the Bright channel's lone coupler.
     
  11. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast

    This would be the cap between instrument volume and pin 6, correct?
     
  12. JohnnyCrash

    JohnnyCrash Doctor of Teleocity

    Posts:
    11,120
    Joined:
    Mar 12, 2005
    Location:
    Fullerton, CA


    Depending on the kit/layout, yes.

    Whichever Volume pot is attached to the Tone pot with a cap... so for some layouts this may mean Pin1, some Pin6.
     
  13. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    Exactly JC, I will keep the original cap values for now. Usually I like to experiment, however in the end of the day I stay within original values.

    I have placed an order for a weber kit without caps, pots and resistors. I placed a separated order for orange drops for coupling, TAD for filter and xicon carbon comp resistors with the exception the ones by the filter caps.

    As far as wiring goes, I have ordered from tube depot a cloth covered solid wire with lacquered cotton braid rated for 600v 20 ga (general) and 18 ga (fil), unlike standard cloth wire, the cotton braid is bonded to the PVC insulator it looks that it might have a neater result and it looks safer.

    The rectifier have opened a lot of issues is the solid state rectifier. I have no clue in what is better, some say that solid state rectifier will save the amp life but other say that it will kill the typical amp's sag. I have order both rectifier tube and copper cap rectifier, can you give any guidance here?

    Thanks

    ps: Sorry for my English folks, my native language is Portuguese.
     
  14. JohnnyCrash

    JohnnyCrash Doctor of Teleocity

    Posts:
    11,120
    Joined:
    Mar 12, 2005
    Location:
    Fullerton, CA


    Generally a tube rectifier (a 5Y3 in this case) results in less voltage and more sag/compression.

    I have my 5E3 on a switch, and the difference between SS or 5Y3 is subtle. SS pretty much makes for a tiny bit more volume.

    In general SS or 5Y3 seems to only noticeabley affect volume (but not by much) in 5E3's... as far as tonal differences, you'd have to increase filter cap size, use SS rectification, AND use a filter choke to make a big difference.

    5E3's will sag and have a bluesier, looser bass in general... but my SS rectifier switch also adds an additional 47uF filter cap at the 1st spot, which may add to the slight difference in bass/tightness that I detect. The only way to start down the "tight" road with a 5E3 is a choke and SS rectification - AND at that point you've lost one of the main characteristics of the 5E3 - so what's the point?

    The point is if you build more than one 5E3 - one for blues or rock, the other for country or rockabilly. The massive midrange honk/bark in the 5E3's preamp/PI can be great for clean old school country - made better if you increase filteration, use SS rect, and a filter choke... in short a stock 5E3 is beautiful for most music, but "fixing" the power section helps for country/rockabilly.
     
  15. SamBooka

    SamBooka Tele-Afflicted

    Posts:
    1,190
    Joined:
    Apr 19, 2007
    Location:
    Montreal
    Great thing about all these amps are... caps cost less than a pack of strings and take about as long to change. My advice: Build the amp stock. Play it .. get to know it. Then make a little change (for example your coupling caps).

    Dont be affraid to ask questions. We are all here for you.

    Good luck
     
  16. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    I'll keep it original, caps and rectifier. The 5Y3GT will suit better my tastes since I like the way this amps sound when overdriven.

    I read that the Sovtek 5Y3GT do not have the exact same specs as a NOS, seems that they hold the amp from sagging prematurely. In any case I can experiment with a NOS Zenith I have inside an old working hi-fi set.

    Thanks
     
    Last edited: Aug 3, 2009
  17. JohnnyCrash

    JohnnyCrash Doctor of Teleocity

    Posts:
    11,120
    Joined:
    Mar 12, 2005
    Location:
    Fullerton, CA


    Modern Sovtek 5Y4's yield higher voltages as well... a pretty good amount more.
     
  18. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    Another issue related with the cathode-resister came up while I was studying the diagram.

    I know that a bigger cathode-resistor lowers the current at idle. A smaller cathode-resistor raises the current at idle.

    Some diagrams spec a 250 [email protected], other spec a 270 [email protected] resistors. What's is the impact on tone going higher or lower with cathode-resister values?
     
  19. tube.tone

    tube.tone Tele-Meister

    Posts:
    352
    Joined:
    Nov 21, 2008
    Location:
    Northeast
    (double post)
     
  20. SamBooka

    SamBooka Tele-Afflicted

    Posts:
    1,190
    Joined:
    Apr 19, 2007
    Location:
    Montreal
    I think 250 VS 270 is just a matter of what is readily available. Because these tubes are self biasing it takes a rather large change in resistance to make a small change in current.
    If memory servers (it usually doesnt so I take notes but my notebook is at home). I change the 470R in my Champ 600 for something in the 800R range to accomodate my
    6K6s
     
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.