Search found 46 matches
- Wed Dec 08, 2021 3:20 pm
- Forum: Technical Discussion
- Topic: Tube Chassis Layout
- Replies: 54
- Views: 2830
Re: Tube Chassis Layout
There is much more to consider than just the "nice" or "rules of thumb" placement. Read the article of Richard Kuehnel ( https://ampbooks.com/mobile/amp-technology/layout/ ). He took a "forensic approach" to Fender's layout principles, very interesting. Base line: Avoid traps for hum and crosstalk, ...
- Wed Aug 18, 2021 10:12 am
- Forum: Technical Discussion
- Topic: Active and Passive Inputs
- Replies: 3
- Views: 1664
Re: Active and Passive Inputs
yes and no the inputs have no gain, they attenuate differently. The questions is, what happens to the subsequent gain stages. An input circuit designed for passive PUs will be overdriven already in stage 1 with unpleasant sound in many cases when too much voltage is fed into it, as the designed gain...
- Fri Jun 25, 2021 10:30 am
- Forum: PCB Design
- Topic: Hybrid turret board / PCB?
- Replies: 7
- Views: 5665
Re: Hybrid turret board / PCB?
Hi, I made a bass amp with this concept, inspired ba a Marshall reissue (forgot the model) and Aiken Amps. Exact same reasoning like yours. The result was perfect and I would do it again. I used turrets no eyelets (not much space inside if several wires meet inside) I made the basic infrastructure P...
- Mon Jun 07, 2021 8:28 am
- Forum: Technical Discussion
- Topic: School me a bit in tone controls
- Replies: 2
- Views: 424
Re: School me a bit in tone controls
Hi, the link above leads you to a simulation but gives no explanation why it behaves like it does. A quite good explanation can be found at AX84: https://ax84.com/archive/ax84.com/static/p1/P1_Theory_Document.zip. It refers to Marshallish Tone stack but you get the idea. There is a short and a long ...
- Tue May 25, 2021 7:11 am
- Forum: Dumble Files
- Topic: SSS Schematics
- Replies: 40
- Views: 52031
Re: SSS Schematics
Hi, the passive filter section before the 3rd amplification stage will attenuate the signal significantly, so the 3rd stage is necessary to keep the signal at a reasonable level. the cathode follower mixing stage will add some compression and thus is crucial for the SSS behaviour, adding sustain thr...
- Thu Mar 04, 2021 9:58 am
- Forum: Dumble Discussion
- Topic: ODS pre with Subminis (complete)
- Replies: 47
- Views: 7419
Re: ODS pre with Subminis (complete)
looks great! Any sound samples yet? I've built a bass preamp with DI-out and an active tone stack with the very same tubes with pleasing results. My tubes are sticking out to the top for cooling reasons and are fenced by drawer handles. Got some PCBs left in case there is interest...(based in Germa...
- Wed Mar 03, 2021 10:01 am
- Forum: Technical Discussion
- Topic: Missmatched 6550s - adding additional bias for each set.
- Replies: 9
- Views: 630
Re: Missmatched 6550s - adding additional bias for each set.
I had a similar problem in an amp and I made a small pcb with 4 trimmers to individually bias each tube. It is a bit fiddly to dial in the values for all 4 when the main bias pot is still in place, but finally worked
got some PCBs left here in Germany
got some PCBs left here in Germany
- Wed Mar 03, 2021 9:56 am
- Forum: Technical Discussion
- Topic: Schematic Software
- Replies: 21
- Views: 1644
Re: Schematic Software
I use SPlan from Abacom Software. It's a small and relatvely cheap german software (49€). There is an english version also. Very simple to learn but not too powerful (no layers, no electrical test, no interfaceto the PCB-SoftwareSPrint, no simulation). Sufficient to make schematics for tube amps and...
- Tue Mar 02, 2021 12:29 pm
- Forum: Dumble Discussion
- Topic: ODS pre with Subminis (complete)
- Replies: 47
- Views: 7419
Re: ODS pre with Subminis (complete)
looks great! Any sound samples yet? I've built a bass preamp with DI-out and an active tone stack with the very same tubes with pleasing results. My tubes are sticking out to the top for cooling reasons and are fenced by drawer handles. Got some PCBs left in case there is interest...(based in German...
- Sun Nov 08, 2020 7:52 pm
- Forum: Dumble Discussion
- Topic: Ryan & Erwin's SSS #002 Madness
- Replies: 187
- Views: 30707
- Thu Nov 05, 2020 1:09 pm
- Forum: Technical Discussion
- Topic: Tonestack Kit App—Now w/ Dumble Simulation
- Replies: 9
- Views: 1231
Re: Tonestack Kit App—Now w/ Dumble Simulation
is the app taken down from the appstore? I cant purchase options and can't find it via search
- Thu Nov 05, 2020 12:55 pm
- Forum: Dumble Discussion
- Topic: Ryan & Erwin's SSS #002 Madness
- Replies: 187
- Views: 30707
Re: Ryan & Erwin's SSS #002 Madness
Hi Dumble Gurus, I'm reading this and other SSS related threads for quite a while now. A friend of mine, a professional guitar player, dreams of a SSS and I was building tube amps for years (and being a lousy bass player). We are going to start the project (hopefully) soon but there is one understan...
- Mon May 20, 2019 11:34 am
- Forum: Dumble Discussion
- Topic: What fuse in 230v amp?
- Replies: 30
- Views: 4396
Re: What fuse in 230v amp?
Please consider: In case, someone uses toroid transformes, the inrush current at startup is way higher than in normal trannies!
- Mon May 20, 2019 11:25 am
- Forum: Technical Discussion
- Topic: silicone for mounting caps
- Replies: 7
- Views: 600
Re: silicone for mounting caps
Hi we build in our company industry computers which are used in rough environments (shock/vibration) and must have a long endurance. For securing components etc. we use Loctite 5145 Tempflex which is dedicated for electronics and is non corrosive and easy to remove in case you have to. It is expensi...
- Tue Apr 30, 2019 8:24 am
- Forum: Dumble Discussion
- Topic: Steel String Singer question
- Replies: 70
- Views: 12573
Re: Steel String Singer question
the schematics they refer to can all be found in the forum somewhere... use the search, it will take some time Moderators: would'nt it be nice to have a collection of the most relevant documentation e.g. re. SSS in one place? There is so much valuable info scattered all around the forum. It is very ...