mwhouston 4,900 Posted June 26, 2020 Share Posted June 26, 2020 (edited) Some maybe interested in the Salt Cellar thread. Suggest you read the article first. It will make more sense. Edited June 26, 2020 by mwhouston Link to post Share on other sites
Tubularbells 6,439 Posted June 26, 2020 Share Posted June 26, 2020 (edited) As famously said in Jaws....im gonna need a bigger boat case 😁 The 3U chassis is proving to be quite the challenge with regards to squeezing in all the Holton goodies. My plans of mounting the PS's to the heatsinks was quickly ended once I did an initial eyeball of the situation so onto plan B & C. Plan B was to mount the power supplies to the bottom of the chassis instead like this with the control module mounted above the transformers. Plan C was to stack the transformers and mount the PS's either side. This imo made for a neater arrangement however the stacked transformers rose like Mt. Olympus above the chassis! Hmmm Only way to solve was to drop the floor a few cm which ment cutting some alloy channel like this. That's much better... Rather than trying to hide this "dropped" floor im instead going to make it a hilighlight so devilish red it shall be but that's a job for the w/e. Edited June 26, 2020 by Tubularbells 2 Link to post Share on other sites
Red MacKay 1,202 Posted June 26, 2020 Share Posted June 26, 2020 38 minutes ago, Tubularbells said: As famously said in Jaws....im gonna need a bigger boat case 😁 Nice Doug - but why are the transistors going to be mounted so high on the heatsinks? These girls are going to pump the power and this is electronics, not plumbing. Heat flows up, not down! I believe you should have the transistors mounted in the lower third of the heatsink, not the top third. Link to post Share on other sites
Tubularbells 6,439 Posted June 26, 2020 Share Posted June 26, 2020 1 minute ago, Red MacKay said: Nice Doug - but why are the transistors going to be mounted so high on the heatsinks? These girls are going to pump the power and this is electronics, not plumbing. Heat flows up, not down! I believe you should have the transistors mounted in the lower third of the heatsink, not the top third. Good callout however since dropping the floor by 30mm the Mosfets will be positioned right at the heart of the heatsink like a wooden stake through a vampire! Not anticipating any heat related issues here mate. Link to post Share on other sites
Guest jakeyb77 Posted June 26, 2020 Share Posted June 26, 2020 1 hour ago, Tubularbells said: As famously said in Jaws....im gonna need a bigger boat case 😁 The 3U chassis is proving to be quite the challenge with regards to squeezing in all the Holton goodies. My plans of mounting the PS's to the heatsinks was quickly ended once I did an initial eyeball of the situation so onto plan B & C. Plan B was to mount the power supplies to the bottom of the chassis instead like this with the control module mounted above the transformers. Plan C was to stack the transformers and mount the PS's either side. This imo made for a neater arrangement however the stacked transformers rose like Mt. Olympus above the chassis! Hmmm Only way to solve was to drop the floor a few cm which ment cutting some alloy channel like this. That's much better... Rather than trying to hide this "dropped" floor im instead going to make it a hilighlight so devilish red it shall be but that's a job for the w/e. Tower of Power Link to post Share on other sites
andyr 5,763 Posted June 26, 2020 Share Posted June 26, 2020 2 hours ago, Tubularbells said: As famously said in Jaws....im gonna need a bigger boat case 😁 The 3U chassis is proving to be quite the challenge with regards to squeezing in all the Holton goodies. My plans of mounting the PS's to the heatsinks was quickly ended once I did an initial eyeball of the situation so onto plan B & C. Plan B was to mount the power supplies to the bottom of the chassis instead like this with the control module mounted above the transformers. What's wrong with the above concept ... if you simply rotate each Holton amp board 180 deg (so the MOSFETs are pointing downwards)? 2 hours ago, Tubularbells said: Plan C was to stack the transformers and mount the PS's either side. This imo made for a neater arrangement however the stacked transformers rose like Mt. Olympus above the chassis! Hmmm Shirley, it is not a good thing to stack toroids like that? Andy 1 Link to post Share on other sites
Tubularbells 6,439 Posted June 26, 2020 Share Posted June 26, 2020 (edited) 5 minutes ago, andyr said: Shirley, it is not a good thing to stack toroids like that? Andy And why do you say that? IMO won't make a beesdick of difference as opposed to using an equivalent 2kv torrioid. Think about what the main advantage of a toroid brings. Edited June 26, 2020 by Tubularbells Link to post Share on other sites
andyr 5,763 Posted June 26, 2020 Share Posted June 26, 2020 3 minutes ago, andyr said: What's wrong with the above concept ... if you simply rotate each Holton amp board 180 deg (so the MOSFETs are pointing downwards)? Just now, Tubularbells said: And why do you that? So the heat is extracted at the middle of the heatsinks - not the top. 2 hours ago, Tubularbells said: Plan C was to stack the transformers and mount the PS's either side. This imo made for a neater arrangement however the stacked transformers rose like Mt. Olympus above the chassis! Hmmm I then commented about the stacked toroids. Just now, Tubularbells said: IMO won't make a bee's dick of difference as opposed to using an equivalent 2kv toroid. You may well be correct - my electrical knowledge is not sufficiently advanced, to know one way or the other. Andy Link to post Share on other sites
Tubularbells 6,439 Posted June 26, 2020 Share Posted June 26, 2020 1 minute ago, andyr said: So the heat is extracted at the middle of the heatsinks - not the top. Red had the same concern so kindly read my response to him. Link to post Share on other sites
HdB 208 Posted June 26, 2020 Share Posted June 26, 2020 Why not mount the transformers on their sides (vertically with angle bracket support or front faces mount) to not waste space - if the diameters are bigger than the 3U height (140mm high?), then add the small bottom spacer to fit. Mount the 2 power supply pcbs vertically with their 2 bottom faces (underneath surfaces) mounted on common central vertical support bracket and position the whole assembly front-to-back. Or maybe mount the 2 power supply pcbs one above the other if it fits. Maybe other ways too ... The extra small control pcb can be mounted vertically in front of the 2 vertical transformer (extra bracket screwed/ mounted on transformer mounting bolts, for example. There's still space on the back panel to mount a possible protection board A bit of lateral thinking here will probably devise better ways than this too. 1 Link to post Share on other sites
HdB 208 Posted June 26, 2020 Share Posted June 26, 2020 Transistors recommended height of transistor body centre on heatsinks is 40% from bottom. This is the centre of the metal face of the transistor, not the mounting hole - you could use 4 "dual transistor mounting pressure clips" each side for this to save drill & taps You need quite a bit of ventilation holes/openings in both bottom and top covers 1 Link to post Share on other sites
Tubularbells 6,439 Posted June 27, 2020 Share Posted June 27, 2020 Well the drugs I took yesterday have worn off (kidding) so have abandoned the transformer stack approach as planned last page and have reverted back to my original plan B which is a more traditional design approach not needing any chassis mods. Control module will be mounted to the front faceplate somehow and power amp modules will be mounted upside down in the heatsinks as centrally as room allows. Power supply now mounted to the bottom chassis plate. 4 Link to post Share on other sites
andyr 5,763 Posted June 27, 2020 Share Posted June 27, 2020 13 minutes ago, Tubularbells said: Well the drugs I took yesterday have worn off (kidding) so have abandoned the transformer stack approach as planned last page and have reverted back to my original plan B which is a more traditional design approach not needing any chassis mods. Control module will be mounted to the front faceplate somehow and power amp modules will be mounted upside down in the heatsinks as centrally as room allows. Power supply now mounted to the bottom chassis plate. So you're now doing what @Red MacKay and I suggested? Andy Link to post Share on other sites
Red MacKay 1,202 Posted June 27, 2020 Share Posted June 27, 2020 Smart move Doug! Your transistors will thankyou for it. Link to post Share on other sites
mwhouston 4,900 Posted June 27, 2020 Share Posted June 27, 2020 I don’t see an issue with Tranni stacking. Link to post Share on other sites
Guest jakeyb77 Posted June 27, 2020 Share Posted June 27, 2020 (edited) 8 minutes ago, mwhouston said: I don’t see an issue with Tranni stacking. Careful 😂 Edited June 27, 2020 by jakeyb77 Link to post Share on other sites
andyr 5,763 Posted June 27, 2020 Share Posted June 27, 2020 1 hour ago, jakeyb77 said: Careful 😂 Andy 1 Link to post Share on other sites
mwhouston 4,900 Posted June 28, 2020 Share Posted June 28, 2020 Audio section of the Salt Cellar amp is complete. Now for the PS section. Link to post Share on other sites
RankStranger 3,579 Posted June 29, 2020 Share Posted June 29, 2020 (edited) The timing’s no good for me but I just got an email saying the Amp Camp Amp parts kits is back in stock at the DIYaudio store, in case someone was thinking about getting one @cram Edited June 30, 2020 by RankStranger 1 Link to post Share on other sites
Ihearmusic 561 Posted June 30, 2020 Share Posted June 30, 2020 Just came across this photo of some speaker stands I made in 2003. I still have the speakers but no longer have the stands. Link to post Share on other sites
RankStranger 3,579 Posted July 2, 2020 Share Posted July 2, 2020 Dual-output Studer 900-based power supply kit that I ordered from China at the start of lockdown and arrived yesterday and I literally couldn’t wait to get a start on it. The transformer is still stuck in transit but I’m pretty sure it’s at least in Australia. They are going to drive my Raspberry Pi and Allo Boss DAC, probably all in the one chassis, although I’m still working out the logistics of that I planned to have a bit more knowledge under my belt before it arrived but, you know how these things go, so I’m putting it together like LEGO without instructions and crossing my fingers that it’s all the right stuff. Link to post Share on other sites
mwhouston 4,900 Posted July 2, 2020 Share Posted July 2, 2020 Before you solder and trim, double check. Getting a part back off is a pain. Good luck. 2 Link to post Share on other sites
bob_m_54 1,501 Posted July 2, 2020 Share Posted July 2, 2020 1 hour ago, RankStranger said: Dual-output Studer 900-based power supply kit that I ordered from China at the start of lockdown and arrived yesterday and I literally couldn’t wait to get a start on it. The transformer is still stuck in transit but I’m pretty sure it’s at least in Australia. They are going to drive my Raspberry Pi and Allo Boss DAC, probably all in the one chassis, although I’m still working out the logistics of that I planned to have a bit more knowledge under my belt before it arrived but, you know how these things go, so I’m putting it together like LEGO without instructions and crossing my fingers that it’s all the right stuff. It's a good idea to try and do some reading about soldering techniques before you start soldering too. The Basic flow of the operation is: 1) Clean the solder side of the board with isopropyl alcohol, and avoid touching it with your fingers afterwards. 2) Prepare component leads (clean and bend with appropriate stress relief and bend radius and width to fit the holes. 3) Insert the leads into the holes paying attention to component orientation. 4) Bend the leads outward slightly to hold the component in position. (unless you're doing clinched joints) 5) Trim the lead length to about twice the diameter of the lead , beyond the solder pad. 6) Solder the leads paying attention to good practices. This will be evident if you read the links I'll post below, especially the inspection pictures. 7) Once the board is finished, clean any flux residue, and coat board with protective spray of some kind. Something like this PCB Lacquer Whether you want to go as full on as some of the things in these, is up to you. But you may want to take note of things like lead bending geometry and maybe improve a few of yours, where they are pulled down hard to the lead hole.. Some good examples of techniques and pictures: http://www.sal.wisc.edu/docs/Soldering Basics.pdf NASA Guide. This is pretty old, but shows good techniques. Have fun :) 3 Link to post Share on other sites
RankStranger 3,579 Posted July 2, 2020 Share Posted July 2, 2020 (edited) @bob_m_54Thanks for the info, Bob I’m ok good at soldering. I’ve done plenty of it before, though mostly just Jaycar kits a long time ago and recapping an amp more recently. I’m not super worried about that, it’s just the electrical engineering side of it that I’m pretty clueless on. I’ll check out the links though. Partly to give myself a refresher and partly because 90s NASA! Cheers, Simon Edited July 2, 2020 by RankStranger 1 Link to post Share on other sites
gibbo9000 242 Posted July 2, 2020 Share Posted July 2, 2020 Looks like a pretty cool kit. +1 for checking before soldering. And just in case . . . the board isn't symmetrical left to right and I would have another look at the transistor to the right of where the right hand electro cap is going to go. If in doubt try to follow the circuitry for symmetry, rather than teh board layout. Gibbo 1 Link to post Share on other sites
bob_m_54 1,501 Posted July 2, 2020 Share Posted July 2, 2020 3 hours ago, gibbo9000 said: Looks like a pretty cool kit. +1 for checking before soldering. And just in case . . . the board isn't symmetrical left to right and I would have another look at the transistor to the right of where the right hand electro cap is going to go. If in doubt try to follow the circuitry for symmetry, rather than teh board layout. Gibbo Good pickup on the transistor. Link to post Share on other sites
RankStranger 3,579 Posted July 2, 2020 Share Posted July 2, 2020 5 hours ago, gibbo9000 said: Looks like a pretty cool kit. +1 for checking before soldering. And just in case . . . the board isn't symmetrical left to right and I would have another look at the transistor to the right of where the right hand electro cap is going to go. If in doubt try to follow the circuitry for symmetry, rather than teh board layout. Gibbo Ooh, good spot! Thanks That’s what you get for stuffing PCBs at 130am instead of sleeping. I’ll double check everything for sure. one thing I did notice is the there are spots for 2 x 15R resistors on the board but I didn’t get any in the kit. The only ones I have left over anywhere near that is a couple of 8R ones. I know there can be variations but that seems too far off. Do I go pick up some 15R ones or should I try to find out if they were deliberately subbed in? Link to post Share on other sites
HdB 208 Posted July 2, 2020 Share Posted July 2, 2020 The Studer supply is pretty generic so shouldn't present any surprises - been around for long time - if you ask the kit supplier for the circuit they'll probably send it to you straight away - suggest you upgrade the big Nover power caps if that's sent. Link to post Share on other sites
muon* 2,748 Posted July 2, 2020 Share Posted July 2, 2020 (edited) I had 8x Nover power caps from a kit in the parts box for several years, they leaked while stored there. Edited July 2, 2020 by muon* 1 Link to post Share on other sites
RankStranger 3,579 Posted July 2, 2020 Share Posted July 2, 2020 1 hour ago, HdB said: The Studer supply is pretty generic so shouldn't present any surprises - been around for long time - if you ask the kit supplier for the circuit they'll probably send it to you straight away - suggest you upgrade the big Nover power caps if that's sent. Thanks, I’ll ask. Link to post Share on other sites
RankStranger 3,579 Posted July 2, 2020 Share Posted July 2, 2020 12 minutes ago, muon* said: I had 8x Nover power caps from a kit in the parts box for several years, they leaked while stored there. Yikes 1 Link to post Share on other sites
muon* 2,748 Posted July 2, 2020 Share Posted July 2, 2020 They came with one of those Chinese clone Naim NAP kits, so no idea if they were authentic Nover or not. Link to post Share on other sites
mwhouston 4,900 Posted July 2, 2020 Share Posted July 2, 2020 3 hours ago, RankStranger said: Ooh, good spot! Thanks That’s what you get for stuffing PCBs at 130am instead of sleeping. I’ll double check everything for sure. one thing I did notice is the there are spots for 2 x 15R resistors on the board but I didn’t get any in the kit. The only ones I have left over anywhere near that is a couple of 8R ones. I know there can be variations but that seems too far off. Do I go pick up some 15R ones or should I try to find out if they were deliberately subbed in? Check every part again. Not a good sign. 1 Link to post Share on other sites
HdB 208 Posted July 2, 2020 Share Posted July 2, 2020 On one of the ZeroZone power supplies kits, the S22 regulator (their version of the AMB Sigma 22) they sent Novers - after a somewhat rude comment, they sent replacement Nichicons and I think are still using them - I tried to get some Supertech's from Taiwan but only bulk quantities. A couple of tears ago, I sourced a whole stack of the "Elna for Audio" 12,000uF/63 from a guy in Djakarta that came from when one of the electronic companies closed down (Sony, Siemens, ..?) Extraordinary good power supply caps. Full of trivia tonight! Link to post Share on other sites
RankStranger 3,579 Posted July 2, 2020 Share Posted July 2, 2020 1 hour ago, muon* said: They came with one of those Chinese clone Naim NAP kits, so no idea if they were authentic Nover or not. I have no idea if mine are authentic or not Link to post Share on other sites
muon* 2,748 Posted July 2, 2020 Share Posted July 2, 2020 54 minutes ago, RankStranger said: I have no idea if mine are authentic or not If the kit looks like quality as far as the PCB and stuff go they are likely OK. 1 Link to post Share on other sites
bob_m_54 1,501 Posted July 3, 2020 Share Posted July 3, 2020 20 hours ago, muon* said: I had 8x Nover power caps from a kit in the parts box for several years, they leaked while stored there. If you'd been sitting in a box for that long, you'd probably need a leak too.. 🤣 1 1 Link to post Share on other sites
crtexcnndrm99 553 Posted July 4, 2020 Share Posted July 4, 2020 Unsure where to post this, but where will I find these carpet underlay style speaker damping sheets in Australia? Going to need a fair amount of it... Similar to this: Link to post Share on other sites
kelossus 1,901 Posted July 4, 2020 Share Posted July 4, 2020 (edited) 54 minutes ago, crtexcnndrm99 said: Unsure where to post this, but where will I find these carpet underlay style speaker damping sheets in Australia? Going to need a fair amount of it... Similar to this: Nigel at Speakerbug sells polyfill as well as the felt-like sheeting you have pictured. He is at Mount Ommaney www.speakerbug.com.au Edited July 4, 2020 by kelossus 1 Link to post Share on other sites
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