Tax Posted August 9, 2014 Posted August 9, 2014 Does anyone have any surplus schottky bridge rectifiers in 1000V 2A and 600V 2A? Please pm me. Thanks
Tax Posted August 9, 2014 Author Posted August 9, 2014 (edited) Any advice on where I could get some Schottky's would also be appreciated. Thnx Edited August 9, 2014 by Tax
Monkeyboi Posted August 9, 2014 Posted August 9, 2014 (edited) What package do you need them in? Does it have to be a bridge configuration or can you use 4 discrete devices to do the same? Found a 5 pin SIL package unit at RS, but it's over $100 for a 600V 5A. Yikes! Four discrete devices to make up the bridge would be a significantly less expensive solution. http://au.rs-online.com/web/p/bridge-rectifiers/0462041/ Cheers, Alan Edited August 9, 2014 by Monkeyboi
PonyTail Posted August 9, 2014 Posted August 9, 2014 I don't think you will have much luck in finding a 1000V Schottky bridge rectifier as schottky diodes are usually rated to less than 100V. There are a few single diodes up to 200V to 250V but above this you need to move into newer technology. SiC or Silicon Carbide schottky diodes such as IDH02SG120 from Infineon are rated at 2A, 1200V have not been around for very long, and I would hate to think what they would cost and the fact that they are a single diode and not a bridge rectifier. Why Schottky instead of ultrafast etc?
Tax Posted August 9, 2014 Author Posted August 9, 2014 (edited) I need it to build this. Advice appreciated. http://www.goodsoundclub.com/PDF/Melquiades_SET.pdf Edited August 9, 2014 by Tax
thoglette Posted August 9, 2014 Posted August 9, 2014 See this discussion on Diy-audio Some heavy hitters there. Cree C4D02120A seem to fit the bill. I think RS components has them for not much $ 2
Monkeyboi Posted August 10, 2014 Posted August 10, 2014 See this discussion on Diy-audio Some heavy hitters there. Cree C4D02120A seem to fit the bill. I think RS components has them for not much $ Agreed. Mouser have these for $3.05 each. Even cheaper in quantity. Discrete devices so the OP will need 12 for each circuit as shown in his follow up post. 1200 PIV @ 2A continuous even more at lower temperatures with 19A surge capability T0-220-2 packaging. Note: tab is not isolated. Data sheet is here - http://www.mouser.com/ds/2/90/C4D02120A-276192.pdf Cheers, Alan
Tax Posted August 10, 2014 Author Posted August 10, 2014 See this discussion on Diy-audio Some heavy hitters there. Cree C4D02120A seem to fit the bill. I think RS components has them for not much $ Thanks! Agreed. Mouser have these for $3.05 each. Even cheaper in quantity. Discrete devices so the OP will need 12 for each circuit as shown in his follow up post. 1200 PIV @ 2A continuous even more at lower temperatures with 19A surge capability T0-220-2 packaging. Note: tab is not isolated. Data sheet is here - http://www.mouser.com/ds/2/90/C4D02120A-276192.pdf Cheers, Alan Excellent Alan! Just ordered some from E14. Thanks! 1
thoglette Posted August 10, 2014 Posted August 10, 2014 I need it to build this. Advice appreciated. http://www.goodsoundclub.com/PDF/Melquiades_SET.pdf Iesus, that's one hell of a way to remove the input capacitor! But if your source has an output capacitor, why have two, I guess?
Tax Posted August 10, 2014 Author Posted August 10, 2014 (edited) Iesus, that's one hell of a way to remove the input capacitor! But if your source has an output capacitor, why have two, I guess? No sure why Romy has done it this way.I have been collecting parts over the last 3 years. Nearly there now. Diodes are the last bit. Nothing bespoke in parts (non audiophile grade) except the custom wound OPT's from Tribute and the custom wound power transformers. Each 500m-A 10H choke weighs 9.5kg each. I hope these mono blocks sound good. Edited August 10, 2014 by Tax
Monkeyboi Posted August 10, 2014 Posted August 10, 2014 Iesus, that's one hell of a way to remove the input capacitor! But if your source has an output capacitor, why have two, I guess? Yep, I'm thinking the same. The amp already has a coupling capacitor C3 in the signal path between the anode of V3 and the grid of V4. I wonder what inspired the designer to use the input stage approach? If R5 went open circuit then about 150v could potentially appear across the input of the amplifier. I wonder how may SS sources or pre-amps are going to have output capacitors rated to take this voltage? What about the possibility of electric shock under this fault condition if you put your fingers across the input? Then there is the issue of noise generated by the OA2 gas regulator tubes. I've seen these used in a HT supply, but never in a grid biasing situation, especially in a relatively low signal level area like the input to an amplifier. These tubes create HF noise when they conduct (perform the voltage regulation function). They also have the propensity to break into parasitic oscillation if shunted by more than 0.1uF of capacitance. It's an unusual and very different design. I've never heard this amp nor built it so I'm probably just brain farting. IMO it seems like a lot of money in parts for an amplifier with a low output power designed to run 15 ohm speakers with a sensitivity greater than 100dB/W/m. Never the less, good luck with the project Tax. This is one design I'd like to listen to, if only to hear what all the fuss is about. I enjoy being pleasantly surprised. Cheers, Alan
Tax Posted August 10, 2014 Author Posted August 10, 2014 (edited) Yep, I'm thinking the same. The amp already has a coupling capacitor C3 in the signal path between the anode of V3 and the grid of V4. I wonder what inspired the designer to use the input stage approach? If R5 went open circuit then about 150v could potentially appear across the input of the amplifier. I wonder how may SS sources or pre-amps are going to have output capacitors rated to take this voltage? What about the possibility of electric shock under this fault condition if you put your fingers across the input? Then there is the issue of noise generated by the OA2 gas regulator tubes. I've seen these used in a HT supply, but never in a grid biasing situation, especially in a relatively low signal level area like the input to an amplifier. These tubes create HF noise when they conduct (perform the voltage regulation function). They also have the propensity to break into parasitic oscillation if shunted by more than 0.1uF of capacitance. It's an unusual and very different design. I've never heard this amp nor built it so I'm probably just brain farting. IMO it seems like a lot of money in parts for an amplifier with a low output power designed to run 15 ohm speakers with a sensitivity greater than 100dB/W/m. Never the less, good luck with the project Tax. This is one design I'd like to listen to, if only to hear what all the fuss is about. I enjoy being pleasantly surprised. Cheers, Alan I am hoping to be pleasantly surprised too!As you may have read in his blog spot and elsewhere Romy the CaT is seemingly different to the majority of us fellow earth dwellers :-) However through experience I have found that some of what he has done in regards to his system is relevant to me. For example he is the one who posted about the Fane Studio 8M in relation to its use in an upper bass horn. Subsequently 11 pairs of these were brought into Oz and all of them went to SNA members or mates of ours and everyone seems to be enjoying those drivers. Before he went off and made his Macondo speakers, he used Avantgarde Duo's and Trios. Both speakers that I am quite intimate with as I used the Fane driver to convert my Duos to quasi Trios. He ran his Avantgarde speakers and HT with no less than 5 pairs of Lamm ML2 power amps which run the 6C33C. Current ML2.2 amps now list at USD$37K a pair. Supposedly he had a falling out with Vladamir Lamm and decided to engineer his own amp giving birth to his Melquiades full range amp. Most of the insides of a Lamm ML2 have similar components. I notice that Lamm in his current ML 2.2 has also decided to go with 3 chokes where previous versions only have 1 choke. The regulation etc is a bit different to the Lamm but I am putting my faith in Romy as he seems to be pedantic in his quest for superior sonics. He has probably spent in excess of $250K along the way with high end products before getting to where he is now so I am confident that he his not "guessing" but speaking from hard earned experience. So at present I am all systems go like a moth to a flame, so hopefully I do not find them too horrible. Should be quite different to PSE 300b's. I have listened to the ML2.1's and while I liked how extended they were in the frequency range, I felt it could do with a bit more in the mids. Hence my going down this arduous path. Will keep everyone posted through my showcase thread. Thanks Edited August 10, 2014 by Tax 1
Number 9 Posted August 10, 2014 Posted August 10, 2014 (edited) you'd be better off using a number of smaller, cheaper and more readily available schottkys in a series/parrallel arrangement (series to get the right PIV with parallel to get the right If ). That's how we were forced to do it back in the early 80s when only low PIV / If devices were available, but it's still the most economical way today. Edited August 10, 2014 by Number 9
Tax Posted August 10, 2014 Author Posted August 10, 2014 you'd be better off using a number of smaller, cheaper and more readily available schottkys in a series/parrallel arrangement (series to get the right PIV with parallel to get the right If ). That's how we were forced to do it back in the early 80s when only low PIV / If devices were available, but it's still the most economical way today. Thanks! Ended up going with what previous posters advised me to obtain from the CREE range from E14 for $85 total.
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