erwin_ve wrote: ↑Tue Jun 09, 2020 6:39 pm
Nice Bas, you did a fantastic job and preparation already. Love to hear the outcome IRL.
Thanks Erwin! It’s actually pretty much all preparation and some assembly lol. So many hours drawing, comparing, investigating, etc.
One thing I haven’t worked out completely. I would like to use 0,5mm2 solid core hookup wire through the amp. Looks like Dumble did that too, at least around the main/preamp board. Really the only supplier I could find is TT in Germany. It says 900V on the website, but insulation is really thin, so I doubt that. All other high voltage cable I could find like Liv-y is stranded, or sold per spool thus expensive. Any ideas/what do you use?
I’m also looking for a nte fet (452?) or 2n4416 (equivalent?). You happen to have any? Maybe we should exchange cell phone numbers, when finished id like to show you this new beast in real life
On.the hookup wire: you can check some aero type related shops. Their wire is usually up to high voltage spec and unfortunatly also expensive.
I can help you with a 2n4416a.
I"ll PM you tomorrow.
Looking great rootz! You got some really huge iron, I am sure it will sound amazing.
I rolled a couple different 6L6 tubes in mine and I ended up liking the Tung Sol 6L6s , they gave the clean signal a smoother sound and held together nicely on the Overdrive channel. I loved the JJ 6L6 in my JM but preferred the TungSol in this amp. https://www.thetubestore.com/tung-sol-6l6gc-str
So you are taking the reverb signal before the Master volume , are you also placing the Level control in back after the Master volume and mixer stages?
Are you also using the same 470k/68K divider were the clean and reverb signal split off and then placing the reverb signal into a cap before it hits the Send Control?
This is the audio file I promised of my build. This is the Overdrive channel no reverb and only running preamp volume at 9 am and overdrive volume at about 10am Level control on back is turned up and Master on front is at 11am. The preamp volume gets turned up a bit at the 56 sec mark.This is with a Les Paul and no fancy mics just the speaker into the audio on my Sony A7 camera.
ODSR1_Audio.wma
Cheers!
Guy
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rootz wrote: ↑Tue Jun 09, 2020 6:15 pm
Yeah, tt chassis. Those come with pre cut holes. The extra inlet will be welded so it is permanently closed. Might get covered by a back plate anyway.
Welding the corners of the chassis - care be taken not to alter too much the outer side - seem to be a good idea but filling the pre-cuts require carefull grounding of the welds afterwards. Grounding looks very much like the tricky part to me - especially if you plan to get a good surface finish at the end.
I wouldn't take chances for that...
Note that 2 mm is not that thick and that welding causes warping too, yet this is a parameter that a good welder should master, too.
rootz wrote: ↑Tue Jun 09, 2020 6:21 pm
Those boards are home made! Simple toner transfer method. I’ve done custom boards before, from China, the US, Belgium. Always top notch but also not fast or expensive. I think those home made boards are very much in the spirit of HAD. Most of his boards I have seen on pictures look hand made...
Yes, I have the exact same impression and that makes me sometimes dream that I could visit his workshop...
erwin_ve wrote: ↑Tue Jun 09, 2020 6:39 pm
Nice Bas, you did a fantastic job and preparation already. Love to hear the outcome IRL.
Thanks Erwin! It’s actually pretty much all preparation and some assembly lol. So many hours drawing, comparing, investigating, etc.
One thing I haven’t worked out completely. I would like to use 0,5mm2 solid core hookup wire through the amp. Looks like Dumble did that too, at least around the main/preamp board. Really the only supplier I could find is TT in Germany. It says 900V on the website, but insulation is really thin, so I doubt that. All other high voltage cable I could find like Liv-y is stranded, or sold per spool thus expensive. Any ideas/what do you use?
I’m also looking for a nte fet (452?) or 2n4416 (equivalent?). You happen to have any? Maybe we should exchange cell phone numbers, when finished id like to show you this new beast in real life
Rootz,
I've used that TT solid core wire on all my Dumble builds, it's great. I use stranded for heater wires.
Do you mean the 0.8mm/0.5mm2/20AWG Type? Dirk at TT just confirmed it is really 900V wire. I guess that is wire to wire, probably 600V to ground. Most wires are specced in a similar way. Still really good insulation properties.
I’ll do the heaters with stranded too. On my Marshalls I did the heaters with 22 (IIRC) AWG solid core. Never a problem. That was the wire Metroamps supplied with kits and had in shop. I wish I could still find that. High voltage, tinned solid core and many colours available.
rootz wrote: ↑Tue Jun 09, 2020 6:15 pm
Yeah, tt chassis. Those come with pre cut holes. The extra inlet will be welded so it is permanently closed. Might get covered by a back plate anyway.
Welding the corners of the chassis - care be taken not to alter too much the outer side - seem to be a good idea but filling the pre-cuts require carefull grounding of the welds afterwards. Grounding looks very much like the tricky part to me - especially if you plan to get a good surface finish at the end.
I wouldn't take chances for that...
Note that 2 mm is not that thick and that welding causes warping too, yet this is a parameter that a good welder should master, too.
rootz wrote: ↑Tue Jun 09, 2020 6:21 pm
Those boards are home made! Simple toner transfer method. I’ve done custom boards before, from China, the US, Belgium. Always top notch but also not fast or expensive. I think those home made boards are very much in the spirit of HAD. Most of his boards I have seen on pictures look hand made...
Yes, I have the exact same impression and that makes me sometimes dream that I could visit his workshop...
Well done, really!
Thanks again for the compliments on the boards man. Appreciate it. During lunch I’m etching the bias, relay power and FET boards. Same method and hopefully the same results.
If I get the corners welded, it will be done with TIG welding. Not so much heat and really tiny welds even on aluminium. And on the inside of the chassis of course so the outside stays intact.
PS (about filling the pre-cut on the back side:) I know TIG and used to weld my own (steel) chassis as well, but I also had hard times at work managing to ground smooth aluminium whose drilling had been filled by a (skilled) welder - because there is often a small depression around the weld (as a side note to your welder, possibly : not to use to much power.)
Some small additions last night. Sadly I’m missing some parts for the FET board and on top of it I killed a Switchcraft 114B that I wanted to use as input jack for the Fet. Bummer!
Anyway, hope to get some more work done this busy weekend.
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I love to see how everyone approach a build. I now tend to do all the peripheral wiring first as I think it is easier to organize the lead dress and which cable is going where. And then I start to add things on top of it. You seem to be doing a bit of both at the same time Rootz! Nice build BTW!
Switchable LNF on V1 ? I've put this on most of my ODS amps, very useful little addition.
How do you kill a jack socket?
M
Yes switchable lnfb! I think I will love and need that with this classic stack and high plates.
Killing the jack socket was easy. The tip connector was pretty bent, so I tried to bend it back. Snap!! There goes my 40 years old switchcraft. Luckily I had a nice Fender switched jack Dumble used on a number of amps. 9 (!!) connections/lugs for a single Jack socket, but it works!
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