Amp build for a first time builder?

[Colossal]

i see what you mean. i have very limited time now though so i can't spend as much time on this as i would like to.

what kit components do you think should be of best quality? which components does it not matter as much?

as i do build the amp i plan to understand what each component does/why certain values are chosen/etc so i can better understand how the amp works. i just dont have time to do all the chassis work, and other finer things like that now.

I'm sure your schedule is rough with all the classwork so can understand that skipping the more mundane aspects of the build process is in your interest. A lot of guys sell just the chassis too so if you wanted to focus some shop time, you could still design and layout your turret boards in your graphics tool and do some minimal fabrication. Watts Tube Audio sells a very wide selection of replica turret boards. Very good materials and workmanship. You could get a chassis from vendor x, your boards from Ken at Watts, and maybe source all your "boo-teek" parts from some of the guitar amp part vendors. It is hard to get everything from one place (this is where kits fill the demand) but you can get exactly what you want; that for me is the big difference. It's like beer. You can get cheap sh*t anywhere and catch a cheap buzz, or you drink from the well.

I think component materials and part choices do matter. Again, not trying to talk you out of a kit but just do your research. You can get some very good deals. Where you absolutely want to spend you money first is on quality transformers. Nobody cares what the chassis looks like, many guys gut old junker amps and repurpose the chassis. Transformers are what you are listening to in a way so avoid off-shore chinese steel. Stick with Heyboer, Edcor, Mercury, and Magnetic Components. From there, get some decent tubes. After that I would go with 1W or higher metal film resistors for your plate loads (anode resistor), carbon and/or metal film resistors in the signal path. If you need to have period-correct specifications then you might have to source some Allen Bradley carbon comps if your project calls for it.

Your choice of amp project will steer you towards what signal caps you might want to use. There are really no "rules" though save for those of electronics (right part rating for the job). You can spend days reading threads with guys arguing this cap over that but it's up to you. There's some easy you-can't-go-wrong solutions for picking caps (definitely look at the gut shots here and see what the guys use for what amp).

[martin manning]

Here's the link to Mojo's instructions for their kit. http://mojotone.com/manuals/Tweed%20Bas ... 2&gc=clear
In the photos you can see how this chassis is laid out, with the controls along one narrow side and the tubes on the oposite side. The transformers, choke and filter caps are mounted outside on the closed side. The cap pan or doghouse is the sheet-metal part shown at the far left in the first picture. For a head version, it would make much more sense to use a wider chassis and put the tubes and transformers on top. That's starting to look more like a JTM45...

As you can see, this chassis is a bit cramped, and there certainly are easier projects that you could start out on. The choice is yours, and there are a lot of choices!

[Firestorm]

A kit is a good place to start. 5F6-A chassis is steel; JTM 45s were aluminium because that's what Jim could buy. Makes a little difference (for arcane reasons). PT does not matter (as long as the voltage is high enough to push the cathode follower over the edge). OT matters tho. Spend your money there.

[yoyohomieg5432]

martin recommended this transformer kit here:
http://store.triodestore.com/bassmanbundle.html

is this a good kit? People have mentioned that MC is a good brand. this bundle says american made but doesn't say what the brand is.

[LeftyStrat]

Don't be crippled by choice. Just build something.

[Firestorm]

martin recommended this transformer kit here:
http://store.triodestore.com/bassmanbundle.html

is this a good kit? People have mentioned that MC is a good brand. this bundle says american made but doesn't say what the brand is.

Buy that PT and choke. We'll have to discuss the OT further.

[M Fowler]

I recommend starting with an amp that has at least a 17x8x2.5 chassis like a Trainwreck Rocket or Marshall JTM45 (KT66) or JTM50 (EL34).

A 59 Bassman 5f6 is not an easy wire job for someone not familiar with tube electronics in that narrow chassis. A 5f1/5f2 or 5E3 yes but not the 5f6.

Mark

[yoyohomieg5432]

martin recommended this transformer kit here:
http://store.triodestore.com/bassmanbundle.html

is this a good kit? People have mentioned that MC is a good brand. this bundle says american made but doesn't say what the brand is.

Buy that PT and choke. We'll have to discuss the OT further.

what's wrong with the OT? i was going to get the 2/4/8 model.

[Firestorm]

martin recommended this transformer kit here:
http://store.triodestore.com/bassmanbundle.html

is this a good kit? People have mentioned that MC is a good brand. this bundle says american made but doesn't say what the brand is.

Buy that PT and choke. We'll have to discuss the OT further.

[martin manning]

martin recommended this transformer kit here:
http://store.triodestore.com/bassmanbundle.html

is this a good kit? People have mentioned that MC is a good brand. this bundle says american made but doesn't say what the brand is.

Buy that PT and choke. We'll have to discuss the OT further.

All of the transformers in the Triode bundle are made by Magnetic Components, in Chicago. You can get the spec sheets for those part numbers on Triode's site or from MC. See: http://www.classictone.net/40-18000.html and http://www.classictone.net/40-18000.pdf MC represents a good value and traditional materials and construction. My recommendation is based on the overall budget (which includes minimizing the number of sources used to keep shipping cost down), and the need to get something that will work with a commonly available 4 or 8-ohm cab as well as in a traditional 4x10 combo at 2 ohms. Hammond makes a similar part which is available from Antique Electronic Supply for about $10 more, so maybe $20 with shipping.

Don't be crippled by choice. Just build something.

[stephenl]

I can vouch for the Marstran OT, I just used his 1207-103 with KT-66's. Heyboer builds it for him. To my ears its a great pairing - I love the sound of a JTM45 with this setup.

The metal work to build a nice chassis is a PITA when your just starting out and don't have the tools - so if your going to build something like a JTM45, buy a pre-punched chassis.

I wouldn't necessarily recommend a low watt amp. Even a 2 watt amp is really loud for apartment playing - but not so good for gigging. VVR and powerscaling work well which will give you an amp for both situations.

Sourcing your own parts will result in better quality but keep in mind that if it takes a lot of separate orders you'll waste $'s on shipping. Its best to pick a project that has an established bill of materials so you can order right the first time.

Educate yourself. Merlin Blencowe has a great site "Valve Wizard" and has written two very helpful books on power supply and preamp design. Kevin O'Conner also has a great site, London Power and good books and kits. The members of this site have huge amounts of combined knowledge as do many of the other forums. Ask questions. AX84 has some great tutorials for beginners. Search for Duncan Amps- he has a free program for designing power supplies for tube amps. You might also be interested in Linear Technologies LTSpice, a free spice program - there are many tube models available.

Amp building is more than slightly addictive......its more like crack.

Have fun. Its very satisfying to play through gear that you've built yourself. It can be very frustrating at first so start simple.

[Firestorm]

A kit is a good place to start. 5F6-A chassis is steel; JTM 45s were aluminium because that's what Jim could buy. Makes a little difference (for arcane reasons). PT does not matter (as long as the voltage is high enough to push the cathode follower over the edge). OT matters tho. Spend your money there.

[martin manning]

A kit is a good place to start.

Some are better than others. The Mojo 5F6-A instructions linked above are prit-ty lame. Note that there is no mention of how the doghouse filters are grounded, and in the photos they are not grounded at all. From what I have seen their product info is lacking in general. For example, the spec sheets for their output transformers show the impedance of each half of the primary as one-half of the a-a impedance. What this tells me is that they don't know how a transformer works. At least they include a disclaimer that says (paraphrasing) "our spec sheets might be totally useless."

[yoyohomieg5432]

lack of a good manual is making me nervous.

i really want to make the 5f6a because i know i'll love the amp when i'm done, but i'm nervous that i'm going to run into problems since there really isn't any good documentation from what i can find.

[Reeltarded]

Post any problems here. Ask lots of questions before you do anything. Get going soon, but you already started.. sort of.

Good start!

Don't be afraid though.