Gauging interest for some metal work

[rootz]

Hi guys,

Lately I've been working on some ideas to manufacture chassis. One in collaboration with another talented builder and Dutch forum member, but some on my own.

I hope it's okay to gauge interest for the first I'd like to produce: the pcb based ODS amps, unofficially known as The Don and Hoyt Axton Dumble. In short these are made like a SSS, but with ODS circuitry. And just very cool amps IMHO!

This is not an inch for inch clone, but it comes very close to the original layout. It will have a presence control and, IEC power socket, fuse for the B+ and a regular DIN socket. A bit modernised and more convenient IMHO.

Still thinking about what finish the chassis should get. Blank and black anodised or silver and black powder coated. I'll be offering board sets too.

So, in short, is there any interest in such a chassis?

[xtian]

"Gauging" interest. I see what you did there.

[rootz]

I don't know. Would 'causing the itch' be an appropriate synonym?

[didit]

Hello -

Seems a worthy scratch. Unclear whether the ocean and other costly obstacles to shipping would make for viable trade into Canada. Picked up a pair of ODS blanks mixed in with a larger order from Tube-Town a while ago, and that was somewhat less of a dent but still.

General oblique plan endorsement -- I've started in on schematics & layout for a set of PCBs derived from that amp. Also with a few modern modification including including on-board switching relays, which HAD had on the OD stage in that amp, and per stage localized power decoupling filters. Moving forward on this at my typical glacial pace.

Best .. Ian

[stephenl]

Would it be worth considering "tubes up". I often wonder why "tubes down" are used in heads (that aren't redundant designs with a combo version).

Better heat management / reliability.

[Guy77]

Your boards are beautiful rootz! I will be finished the build in 2 weeks. Excited to power this up!
Here are some pics below. Your chassis will make things a lot easier for everyone!

I installed a pot below the overdrive board is the overdrive entrance trimmer can be accessed outside the amp.
I made mine as a low plate on the clean and high plate on the overdrive with a classic tone stack.

The large switch on the far left in one of the pics is for a pentode/triode switch, this has become one of favorite mods these days. I love the warm compressed sound in triode mode. My power transformers are stand up.


Cheers

Guy

[dorrisant]

Great looking work.

How are we gonna partake in the US? Files?

[rootz]

Shipping to the other side of the world will never be very cheap I'm afraid. Some 10 years ago I ordered a kit from Metro amps. Shipping alone was $170 IIRC and I had to add customs and VAT to that. That was a dent indeed!

I checked shipping costs quickly. Without handling and taxes shipping is around $35/40 to the US from The Netherlands, with track & trace. The maximum size of the box is 100x50x50 cm. So you could ship 40 chassis in one box and thus pay only $1 per chassis on shipping, lol. But seriously, it opens up the prospect of doing a group buy.

I'm curious: what and how much additional costs does one get in the US or Canada when ordering from the EU? In The Netherlands the calculation is as follows: ((product price + shipping) * customs) * VAT. Mostly pretty expensive and one of the reasons I never ordered e.g. Classictone transformers.

Guy, very good to see the boards are being used! That's going to be another great build. You are right, a chassis that is made for these boards will make life easier.

I'm adding a some more renders of the chassis (version with cage nuts) to make clear how the boards fit. The boards should be black, but I can't seem to find a way to edit their colour in Eagle. I currently don't have a design for the PSU board, but will come up with one that is able to take axial caps from F&T, IC, Sprague TVA.

[rootz]

Just a quick follow up. Got some chassis/test beds in this week. Some room for improvement: I do not like the open corners. Those will remain visible. This will be dealt with. But overal pretty happy thus far!

At the same time I’m working on some other chassis projects. See if you can spot this one.

[rccolgan]

Wow you picked up chassis making quick! I'm in if you want to do a Dumbleland too

[rootz]

Dumbleland? Sure Ryan, let’s do that! Sent me a pm please and we’ll make a start.

Just got the first batch of boards for ‘The Don’. Matte black and man these are such a perfect fit and will look awesome in either a black or silver chassis.

[rootz]

Time for a small update on the work here. It’s going a bit slow during the vacations and with all the other work I’m doing, but it’s going at a steady pace though.

So what happened? I finalised the design of the chassis for both the ODS and 005. I’ve got 10 pcb sets available for both. Now it’s onto finishing and screen printing the chassis.

Still in debate with myself on the finish: powder coat or anodising. Also on what colour the ODS should be. Black with gold lettering like Hoyt Axtons amp, or silver with black lettering like The Don from Bonamassa. What do you think?

[Bombacaototal]

Looking great!! On the 005 bias supply, did you use 2x22uF or 2x47uF, and the resistor in between, 15K or 25K

[Guy77]

Beautiful work Bas!
Your boards from the "Don" amp have been running in one of my customers amps and he loves it!

I like the idea of Silver powder coat and black lettering for the Don amp like Joe's B. amp.
But what ever you choose I am sure it will look great!
Cheers

Guy

[rootz]

Thanks! I do have 2x47uF and 22k in there now. I have to experiment what that combo gets me. The PT is custom build for me, with multiple high voltage primaries, 5V @ 6A, 6.3v @ 7A, 12V @ 0.7A. Really versatile and works with 2x6L6, EL34, 6550 or 4x6V6. That also means I might have to do some experimenting to get the voltages right. If my predictions and simulations are right, the preamp voltages are more in line with what you'd see in an ODS and not as high as in some 002 samples I've seen.