Amp build for a first time builder?

[tubeswell]

5F6A is the king of blues amps. A bit more complicated to build than a 5E3. A Weber 5F6A would slay a RI Fender '59 Bassman LTD, because the Weber speakers are just so awesome.

[martin manning]

wow, after firestorm mentioned the 5F6a, i looked it up and i'm really liking what i hear from that.

has anyone ordered from here: http://taweber.powweb.com/store/kits_50a.htm ? I'm interested in the 5f6-a head. Does this come with the head shell as well and transformers? The price seems too good.

Direct link to Weber 5F6-A head: http://taweber.powweb.com/store/kits_50a.htm#5F6AH The schematic and layout both show a single 2-ohm output (with jacks for four parallel 8-ohm speakers). If I were building a 5F6-A as a head, I'd want a multi-tap OT. Note also that many people claim that a big part of the Tweed Bassman sound is its 4x10 speaker and floating baffle arrangement.

Weber kits are among the least expensive options. I've never seen one, but I've heard some complaints about part quality in the past. On the first page of their web site they say thay are now using Carling switches and Neutrik jacks (good quality parts). That, as I recall, was one source of the complaints. Weber speakers are among the best available for reproductions of the classic american designs.

Check out Mojo's version of a Tweed Bassman kit, priced at $1025: http://www.mojotone.com/amp-parts/amp-k ... lifier-Kit , and have a look at the instruction "manual" (its a few pics showing intermediate progress points) to see what the assembly process looks like.

[Structo]

I have also heard that Weber has stepped up the quality of their components.

If you find a part that does not meet your standards, it wouldn't be that difficult to replace it with something you like.

[johnnyreece]

I've built a couple Weber kits and some of the parts are definitely replaceable. Pots are a common complaint anymore. I personally don't mind them, but the taper leaves a lot to be desired for some. The cabs are a great deal, if you're not building your own. Trannies are solid, chassis are good. Resistors are metal film, if you care. Tubes are cheap Chinese, but they're good for initial startups, and will work if you don't want to spend more coin.

[martin manning]

This is one drawback to building from a kit, i.e. you have to buy the selected parts. Fortunately there are often options available for certain parts, or options to delete certain parts so you can source them yourself. Most important if you want to end up with something that is faithful to the original in tone, be concerned with the big stuff like transformers and speakers first, and I guess I'd put capacitor type in that category too. Some stuff you have to accept winds up in your junk box, and won't ever get used except as an experiment or unless you have no other options.

[yoyohomieg5432]

wow, after firestorm mentioned the 5F6a, i looked it up and i'm really liking what i hear from that.

has anyone ordered from here: http://taweber.powweb.com/store/kits_50a.htm ? I'm interested in the 5f6-a head. Does this come with the head shell as well and transformers? The price seems too good.

Direct link to Weber 5F6-A head: http://taweber.powweb.com/store/kits_50a.htm#5F6AH The schematic and layout both show a single 2-ohm output (with jacks for four parallel 8-ohm speakers). If I were building a 5F6-A as a head, I'd want a multi-tap OT. Note also that many people claim that a big part of the Tweed Bassman sound is its 4x10 speaker and floating baffle arrangement.

Weber kits are among the least expensive options. I've never seen one, but I've heard some complaints about part quality in the past. On the first page of their web site they say thay are now using Carling switches and Neutrik jacks (good quality parts). That, as I recall, was one source of the complaints. Weber speakers are among the best available for reproductions of the classic american designs.

Check out Mojo's version of a Tweed Bassman kit, priced at $1025: http://www.mojotone.com/amp-parts/amp-k ... lifier-Kit , and have a look at the instruction "manual" (its a few pics showing intermediate progress points) to see what the assembly process looks like.

i've only got about 550 to spend so the mojo won't work out for me.

the head is in my price range, is it easy to find a 4x10 cab down the road when i have the money for it?

as far as the output impedance, is it as easy as changing out the OT for one that is multi-tap? Or is there much more involved in this?

[martin manning]

You'll need a 2-ohm cab to play the amp. Changing the OT for a multi tap version would take care of that, but be aware that you might run into difficulties if the mounting holes are on different centers. Also transformers are a significan fraction of the cost of an amp- a Bassman OT with 2-4-8 or 4-8-16 outputs will cost ~$70 (Magnetic Components 40-18000 or 40-18001, available from Triode Electronics), and the original OT will become a nice 2-ohm doorstop. Really the original Fender chassis design is best installed in a combo cab. I don't know if that is the design Weber is using in the head kit or not. If you're never going to build it into a 4x10 combo, then this is not the best choice for a chassis. Google up some images and you'll see what I mean.

Here's another option- make up your own kit for the chassis, and get a combo cab and speakers later:

Item Source Description Link Price
Transformers Triode Bassman Bundle w/ 2/4/8 ohm OT http://store.triodestore.com/bassmanbundle.html $168.83
Tubes Triode Bassman Re-tube set http://store.triodestore.com/5d6bassmanretube.html $94.95
Sm Parts Kit Mojo 5F6-A Boards, pots, jacks, resistors, caps, hardware http://www.mojotone.com/amp-parts/amp-k ... -Parts-Kit $127.00
Chassis Mojo Chrome Steel Chassis http://www.mojotone.com/amp-parts/Chass ... F6-Chassis $84.00
Cap Pan Mojo Filter capacitor board cover http://www.mojotone.com/amp-parts/Capac ... nformation $22.50

This comes to just under $500, and will get you a working chassis. It's likely, but not guaranteed that the Mojo chassis will accept the MC transformers as drilled. You could check that out before ordering.

[yoyohomieg5432]

thanks for laying that out.. that's probably what i'll go with!

couple questions: what does the MC stand for in MC transformer?

if they don't fit, its just as simple as having to drill my own hole right?

also, what's the point of the filter cap board cover? I don't think ive seen this before in other kits. aren't the filter caps inside the chassis? Why would it need another cover?

[Colossal]

Dude, if you are studying engineering, you owe it to yourself to build an amp from parts, from the ground up. This is a rite of passage in your education. Some things were truly better in days of yore.

isn't that what i'm doing? if i get a jtm45 kit it's all parts. the ceriatone was the only one that had the pre assembled turret board

No not really; you're looking to buy a kit and have all the part sourcing done for you. Then it's solder by numbers. I would think as an engineer you'd be interested in getting below the surface to look up each part value in the amp you've chosen from the schematic, source it out via price comparison between vendors, pick your transformers, buy a blank chassis and put your shop tool access to use. There's no reason you couldn't build a stellar amp that far outperforms most available kits. Most kits build a working amplifier. The suppliers of most of these kits are looking to shed value to create a wider profit margin. As previously mentioned, the part quality in Weber kits is marginal at best, Ceriatone you're gonna have a shipping premium.

You can get everything you need from Watts Tube Audio, Tube Depot, Angela, Mouser Electronics, Magnetic Components, Heyboer, Edcor, or Mercur, etc etc and it would take a couple of hours of surfing and identifying your parts and vendors in Excel. Build your own bill of materials. Execute your orders. Amass parts, lay them out on cards and ID their values. Write your order of assembly. Design your chassis hole cutouts and turret boards in graphic software, 1:1 scale. Print your templates, tape over boards and chassis, spend 2 hours in the shop drilling methodically. Assemble the chassis, mount transformers, wire. Check continuity, etc. Step back and consider your work with pride.

That's different from buying a kit. You will come out either being able to solder by numbers or you will master basic electronics and have a deep understanding of voltage amplification.

I'm not telling you what to do, do what your budget, interests, and time allow but I'm pointing out the differences between one approach and the other.

[Phil_S]

what does the MC stand for in MC transformer?

Mangetic Components...just the name of the manufacturer.

if they don't fit, its just as simple as having to drill my own hole right?

More or less. It's not a big deal unless it misfits in an inconvenient way. Chances are, it's not a problem.

what's the point of the filter cap board cover

Fender designs call for a "dog house" to cover the caps mounted OUTSIDE of the chassis!

[Colossal]

couple questions: what does the MC stand for in MC transformer?

MC = Magnetic Components. Old School quality transformer mfr. in Chicago.

also, what's the point of the filter cap board cover? I don't think ive seen this before in other kits. aren't the filter caps inside the chassis? Why would it need another cover?

Fender amps locate the high voltage supply on the outside deck of the chassis. For safety, the "dog house" cover is there to keep errant fingers out of harm's way.

[Colossal]

Haha, posted same time you did Phil. Ravens are getting a beat down courtesy of the Houston boys today

[skyboltone]

So, are really serious about wanting to learn to build tube amps or are you just looking to for another amp as an alternative to your Marshall and you think building one is cheaper than buying one?

I'm sure you didn't pop out of the womb walking; therefore if you are truly interested in learning then there is nothing wrong with crawling before walking. A simple "one, two knob" amp would be perfect on so many levels. For example, a basic Champ circuit would be great for it's ease of assembly, getting you comfortable working around high voltages, troubleshooting and performing simple modifications. Then, if you decide this is something that you would like to grow further with, move on to more complex circuits.

That's my advice..............


TM

Just what I was thinkin'

[yoyohomieg5432]

Dude, if you are studying engineering, you owe it to yourself to build an amp from parts, from the ground up. This is a rite of passage in your education. Some things were truly better in days of yore.

isn't that what i'm doing? if i get a jtm45 kit it's all parts. the ceriatone was the only one that had the pre assembled turret board

No not really; you're looking to buy a kit and have all the part sourcing done for you. Then it's solder by numbers. I would think as an engineer you'd be interested in getting below the surface to look up each part value in the amp you've chosen from the schematic, source it out via price comparison between vendors, pick your transformers, buy a blank chassis and put your shop tool access to use. There's no reason you couldn't build a stellar amp that far outperforms most available kits. Most kits build a working amplifier. The suppliers of most of these kits are looking to shed value to create a wider profit margin. As previously mentioned, the part quality in Weber kits is marginal at best, Ceriatone you're gonna have a shipping premium.

You can get everything you need from Watts Tube Audio, Tube Depot, Angela, Mouser Electronics, Magnetic Components, Heyboer, Edcor, or Mercur, etc etc and it would take a couple of hours of surfing and identifying your parts and vendors in Excel. Build your own bill of materials. Execute your orders. Amass parts, lay them out on cards and ID their values. Write your order of assembly. Design your chassis hole cutouts and turret boards in graphic software, 1:1 scale. Print your templates, tape over boards and chassis, spend 2 hours in the shop drilling methodically. Assemble the chassis, mount transformers, wire. Check continuity, etc. Step back and consider your work with pride.

That's different from buying a kit. You will come out either being able to solder by numbers or you will master basic electronics and have a deep understanding of voltage amplification.

I'm not telling you what to do, do what your budget, interests, and time allow but I'm pointing out the differences between one approach and the other.

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.

[Phil_S]

Haha, posted same time you did Phil. Ravens are getting a beat down courtesy of the Houston boys today

Ouch! 43-13. Ray Lewis on the sidelines is a real problem.

Haha, too. We gave the same answers!