First build ODS clone

[mr_chrish]

Hi!

I'm totally new to building and modding amps, so I have a few questions:

1) Where do you get the parts, and how much would an ODS clone cost when building it from scratch?

2) Is it at all possible for an inexperienced builder as myself to build a clone? I'm studying electronics, so I can read basic schemactics and layouts.

3) I live in Norway were we use 230V, any mods for that?

Thanks,
Mr_chrish

[seulb-rd]

cheers and welcome!

don't know if i would recommend a d-type as a first amp. it is a fairly complex beast. likely you would get it to work, ie get sound if you plug a guitar in one end and a speaker in the other. but what comes out of the speaker may not be what you expect. read the posts in discussion area and you'll see even experienced builders are often puzzled as to how to get 'the sound'. having said that, my first build was a super reverb. probably too complex for a beginner, but i never asked advice i just dove in. so, if you want a d-type, go for it. plenty of folks here happy to help you out.

230 should be no problem just get a pt built for that main voltage. some euro builders do comment on difficulty finding rn65 metal film resistors. couldn't tell you about prices over there.

[mr_chrish]

Thanks for the tips. It's not very important that it'a ODS, I'll read some more and see if I can find a more suitable first build. I'm not in a hurry, and I'm open to your inputs.

Thanks,
Mr_chrish

[seulb-rd]

check out www.ax84.com and www.18watt.com . ax84 has a number of well documented amp schemos and some are available in kit form. virtually all would be far less complex than a d-type. 18watt is devoted to the clones of the marshall 18 watt. great sounding amp and easy to build. also, plenty of kits out there.

hth

[mr_chrish]

I have been reading quite alot of the posts and it seems to me that the most of you have a donor amp or a amp that you mod. In the start I was thinking that I would be able to find or make a list of the parts and components and then just order the most of it. Was I wrong? What's the best way to start a build?

[ODwan]

Hi,
I don't know if there are suppliers in Norway, but check out www.tube-town.de and www.banzaieffects.com. They ship to Norway, too.
Concerning the pricetag for a from-scratch-build I would say at least 300-400 Euro including some components to tweak. If you build on of this amps be sure to have plenty of tweaking components handy!
Most costly would be the transformers and the choke. Say 100€ PT, 100€ OT and 20-30€ choke. A decent Hammond chassis about 30€. The next big thing would be the PS capacitors, prices varying with what you use. Then the potis and the coupling caps with 1-2€ each. I hope this helps a bit.
I have made a habit of not calculating costs before a build in order not to keep me off it!

Keep rockin'

Timo

[mr_chrish]

Thanks, this helps quite a bit!

Found this: http://ampgarage.com/forum/download/file.php?id=394 , does anybody know how incomplete this is, and which layout/schematic it belongs to?

Any tips on the first couple of things I need to do before I start building? I'm finding it hard to known where to begin.

Thanks,
Mr_chrish

[skyboltone]

Hi Mr.
Components are very critical I'm told. You won't find most of the gurus on this forum going near carbon film resistors for signal path. Use Vishey/Dale RN-65 type. Mouser.

These lists are just a start I've found. You have to go by the schematic part by part plus all the stuff that doesn't show on the layouts. Like transformers, cords, rear panel jacks and switches, turret strips and boards, knobs, pilot lights, feet and handles, woodwork, chassis, faceplates, on and on.

With the dough I have in mine so far, I could have bought a pretty nice Twin Reverb. Oddly enough though, it wouldn't stretch to a black face deluxe.

Anyway, on the Dumble forum, check out funkaliciousgroove's chassis project. He'll have pre-amp boards and the whole shootin match to get you started.

Tools; a good soldering iron, a good multimeter and some good safe work habits. Check Ebay for a bench type multimeter for cheap. Restrict your choices to Fluke, Hewlett Packard, Kiethley, or the rare Tektronics. Anything else will just cause you grief. There are industrial clearance outfits out there selling some pretty nice equipment for pennies on the dollar.

Good luck
Dan

[Bob-I]

Any tips on the first couple of things I need to do before I start building? I'm finding it hard to known where to begin.

Thanks,
Mr_chrish

First, you need to commit to a schematic and layout. Once you've done that, start sourcing out your parts. Be careful to order from as few sources as you can so you don't get killed with shipping costs, and also be careful to order everything you need. I typically order in 10's, so if I need 2 caps, I buy 10 and stock the rest.

Once you have the parts collected, assemble the big parts onto the chassis. Transformers, tube sockets etc.

Wire up the board, installing all components based on the layout and including all leads.

Install the board and wire up everything inside the chassis. I typically do it in this order....

1) All power from the AC input to the fuse, switch, xformer etc.
2) Wire up the heaters... stop cursing and finish it up, the rest will be easier.
3) Wire up the tube sockets, starting at one end and working your way across.
4) Wire up the controls.
5) Wire up the output
6) Hard wire in the clean channel.

Once all this is done, walk through the schematic and layout doublechecking that all connections are correct and complete.

Disconnect the power xformer secondaries, tape them off and test the AC connections.

Reconnect the power xformer and check the DC with no tubes installed.

Add the tubes and go for broke. I use a lightbulb wired in series with the AC input to limit current for the first power up.

When (not if) you get no sound, or bad sound, triple check the schematic and layout drawing and fix whatever mistakes you find.

Once the clean channel works right, hard wire the OD channel and do the same checks.

Finally wire up the relays then start tweaking.

Good luck.

[mr_chrish]

Thanks guys, this is exactly what I've been looking for!

I've desided to go for a Hybrid-A type amp, and lately I've been converting Ben Sheltons drawing

http://ampgarage.com/forum/download/file.php?id=597

into a Visio layout. I think it's based on one of the Hybrid-A shematics found here:

http://ampgarage.com/forum/viewtopic.php?t=388

In Visio I've taken myself the liberty of using Normsters ODS layout Visio files as a source and inspiration for components and such

http://www.bad-domain/6V6_ODS/.

I'm not done yet, but I'll post then result when it's ready for inspection. As I'm low on cash at the moment I can't order any parts, so I have plenty of time to make a good layout and do my preparetions well.

Living in Norway there are two things that worry me:
1. We use 240v in our wall sockets. Is that as easy to fix as just to use different connectors on the PT?
2. It's seems hard to find a good chassis, but I think a friend of mine could make me one if I had a desent drawing. Any thougts?

Oh, and finally, could someone give me a really quick guide of the relays, how they work, what's their purpose ect? I just have to see if I understand them correctly.

Once again a humble thank you,
Christian

[skyboltone]

Living in Norway there are two things that worry me:
1. We use 240v in our wall sockets. Is that as easy to fix as just to use different connectors on the PT?

There are lots of power transformers with dual voltage primarys 120/240. No porblem.
2. It's seems hard to find a good chassis, but I think a friend of mine could make me one if I had a desent drawing. Any thougts?

Once again, check out Funkaliciousgrooves chassis. I couln't wait so I had one custom made by a guy on Ebay. I'll have to punch all the holes and make a faceplate but I'm happy with the decision. Just draw a box 19X3X8 or nine inches (millimeters over there) sorry. Make sure your sheet metal outfit welds the corners. Some guys turn a .5" lip all around the opening some just on the ends to make it easier to wire pots. I had mine made with .080 aluminum and with the lip all around. You could prop your car up with it. Plenty strong.

Oh, and finally, could someone give me a really quick guide of the relays, how they work, what's their purpose ect? I just have to see if I understand them correctly.

The switches shown on the RevA schematic for PAB/HRM and OD channel are Double Pole Double Throw toggles. DPDT. (ON-ON with NO CENTER OFF) If you replace the function of those switchs with a relay you can control those functions with a foot switch. A relay has a magnetic coil that sucks the switch parts into contact when energized with electricity. They come in a bewildering array of types and sizes and functions. Use the low tech models with the DPDT form factor at 6 or 12 or 24 volts. You then need to design and install a separate power supply for the relays. There are tons of posts on that very topic.
Once again a humble thank you,
Christian

Good on ya for learning Visio. I'm looking for a brain transplant so I can learn it too.

Dan