pinnocchio said:
I could not accomodate a two pin part and would need 16@3.14 so it would be an expensive test. I only need 8@0.81 of the EOL parts per pcb and would be happy to purchase qty40 and share. Since I will be shipping caps anyway, want me to order?
I think either of the parts would work well. _I_ have no plans for massProd
I blow quarter amp fuses without thermistors and if I put in larger the amp becomes the 'fuse' 🙁
@qusp Was typing when you responded so it would be your turn to sigh at me 🙂
The Cree looks really nice, I must admit. In these power supplies I used transformers with four secondaries, a pair of 9's and a pair of 15's. They are wired for dual 24vac for JC-80 but can easily rewired and the Kubotas adjusted to power 'the wire'.
The Cree looks really nice, I must admit. In these power supplies I used transformers with four secondaries, a pair of 9's and a pair of 15's. They are wired for dual 24vac for JC-80 but can easily rewired and the Kubotas adjusted to power 'the wire'.
I could not accomodate a two pin part and would need 16@3.14 so it would be an expensive test. I only need 8@0.81 of the EOL parts per pcb and would be happy to purchase qty40 and share. Since I will be shipping caps anyway, want me to order?
I think either of the parts would work well. _I_ have no plans for massProd
I blow quarter amp fuses without thermistors and if I put in larger the amp becomes the 'fuse' 🙁
Sure, order them and I will share with you. Just PM me the final amount and your paypal email address.
Then you can get a soft start that would use either resistors or thermistors and after a second a relay bypass. I have build this one and it works pretty good for my Aleph 5 amp but I replaced the resistors with thermistor and added a 5 seconds delay since I have 100000uF caps per channel.
Soft-Start Circuit For Power Amps
Ciao!
Do
Transformer Voltage too low
That's why we test. 😡 With 27vac I cannot hold 30vdc into the cap multiplier with both rails loaded(which in turn does not hold 24). Back to the r-core vendors. There is simply more drop across the rectifiers and regulators than I expected. Given that the drops were symmetrical I doubt it is a component issue (other than 27vac being low).
That's why we test. 😡 With 27vac I cannot hold 30vdc into the cap multiplier with both rails loaded(which in turn does not hold 24). Back to the r-core vendors. There is simply more drop across the rectifiers and regulators than I expected. Given that the drops were symmetrical I doubt it is a component issue (other than 27vac being low).
While blocked on r-cores
The copper transistor thermal bonding can be easily fabricated if you begin with a length of 3/16" solid rod. Grind a flat on one side so it approximates the shape of the transistor body. You will need enough 'slices' to accomodate eight transistors. I found it easier to mold roughly 3" of copper around the rod and solder it shut. Remove the rod, cut the copper into two pieces, solder those together and then slice like a 'jelly roll'. This is easier said than done. Grinding the flat is easier for brass, removing after soldering easier for steel
The copper transistor thermal bonding can be easily fabricated if you begin with a length of 3/16" solid rod. Grind a flat on one side so it approximates the shape of the transistor body. You will need enough 'slices' to accomodate eight transistors. I found it easier to mold roughly 3" of copper around the rod and solder it shut. Remove the rod, cut the copper into two pieces, solder those together and then slice like a 'jelly roll'. This is easier said than done. Grinding the flat is easier for brass, removing after soldering easier for steel
Maybe we could start a raffle for Blowtorch boards. At a dollar a ticket we just need to sell 5000 tickets. I'll sell the tickets and my next door neighbour, who knows nothing about audio or electronics, will surprizingly win ( as I intended) and give me the boards as he wouldn't know what else to do with them.
Sort of like the guys who broke into the Kremlin and stole next year's election results.
I guess we can't sell raffle tickets to John - it just wouldn't look right if he won.
Sort of like the guys who broke into the Kremlin and stole next year's election results.
I guess we can't sell raffle tickets to John - it just wouldn't look right if he won.
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something like the DSEP15-06A would be not too high overkill for your purposes here. they sell them for a 50-100% markup at PCX and will export, i dont know why digikey wont, maybe because there are some of their higher end parts that are milspec and just as DK wont export the ITT cannon high voltage umbilical connectors, they wont do it here. i like their to-247 parts like the DSEP30-06A, but using a 600V 30A rated diode for a headphone amp seems a bit OTT hehe
I believe I can get them from Digikey since I'm in Canada. If you want some, let me know. I'll place an order for you!
Do
thanks!! i may just take you up on that, i need diodes for my AJX and depending on the results of the switcher comparisons; the wire power amp (fullsize with laterals) need to decide whether i'll go dual common cathode parts or single diodes. a favorite for the common cathode part is DPG60C300HB-ND, so about 80 bucks in diodes, not too bad for amps of this quality and i already have all the other parts. it'll be a little bit yet, a few weeks probably. thanks very much for the offer. i was meant to get them with a large order i got my friend in the states to pass on, but when i exported the BOM it removed them due to the non export thing and i didnt notice
I would like to remind everyone that the Blowtorch was designed in the late 90's, when there were plenty of 'paper' millionaires in the USA and elsewhere. We were given a chance to make the BEST that we could possibly make, not only for ourselves, but for about 40 other 'discerning' individuals. The Blowtorch was designed to be a 'race car', in order to win listening contests, with a minimum of features or user convenience.
The efforts we took, like super selected fets, Teflon circuit boards, etc, etc, cannot be made at any 'reasonable' price point, so compromise is necessary, for most here. However, these compromises are mostly trivial, unless you are into competitive listening contests, as is done by wealthy audiophiles across the world. It is a bit like needing a car that can exceed 150mph, how many of us need this?
The efforts we took, like super selected fets, Teflon circuit boards, etc, etc, cannot be made at any 'reasonable' price point, so compromise is necessary, for most here. However, these compromises are mostly trivial, unless you are into competitive listening contests, as is done by wealthy audiophiles across the world. It is a bit like needing a car that can exceed 150mph, how many of us need this?
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I don't need one, so I guess I'm all good! 😀
I would however take one if given to me! Zoom Zooom!
But trust me, with all the brains combined we have in here (getting closer to yours! 😀 ) we won't be driving a chevy! 😉
Ciao!
Do
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I am waiting for the Actual Blowtorch to show up as used - available on ebay or Audiogon for a reasonable price. I will buy it!
2000$ for the stuffed /tested Blowtorch boards is still attractive but beyond my buying capacity unless I win a powerball lottery
I am happy with my Vendetta Research SCP2
kannan
2000$ for the stuffed /tested Blowtorch boards is still attractive but beyond my buying capacity unless I win a powerball lottery
I am happy with my Vendetta Research SCP2
kannan
Don't give up hope just yet but I would doubt people would just get rid of them... These are also going to be collection pieces with only a few of them out there! I sure wish I was the proud owner of one of them!
Do
There have been one or two Blowtorchs for sale on Audiogon over the years, but they went quickly and not cheaply. So either it's John's boards which are a deal if you want one .......... or my raffle tickets. John's right - you can build a close enough version incorporating similar design and build details to make a great preamp, you can build a good JC- 80 inspired preamp and be most of the way there. I was lucky enough to have enough high V group duals to match and an exacto blade and the obsession to go farther
Feed both boards with Borbely's super shunts and a good raw supply CLC then LT1085/LT1033 with external LM 329 references (overkill as 317/337 will do fine). I have it going into a SAE MK 1 early 1970s metered preamp chassis (with new meter drivers) with just a Shallco selector and stepped attenuator, new jacks and wiring. The SAE cost $ 500 to get a classic chassis for mounting the preamp. You need one with room because of the all the regulator and preamp heatsinks. John used the chassis of the Blowtorch as the heatsink for both the output and regulator TO 220 devices helped keep the bias levels high and the signal path short. If you use a Carver or NAD chassis John may repossess your boards without notice...........
Feed both boards with Borbely's super shunts and a good raw supply CLC then LT1085/LT1033 with external LM 329 references (overkill as 317/337 will do fine). I have it going into a SAE MK 1 early 1970s metered preamp chassis (with new meter drivers) with just a Shallco selector and stepped attenuator, new jacks and wiring. The SAE cost $ 500 to get a classic chassis for mounting the preamp. You need one with room because of the all the regulator and preamp heatsinks. John used the chassis of the Blowtorch as the heatsink for both the output and regulator TO 220 devices helped keep the bias levels high and the signal path short. If you use a Carver or NAD chassis John may repossess your boards without notice...........
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There have been one or two Blowtorchs for sale on Audiogon over the years, but they went quickly and not cheaply. So either it's John's boards which are a deal if you want one .......... or my raffle tickets. John's right - you can build a close enough version incorporating similar design and build details to make a great preamp, you can build a good JC- 80 inspired preamp and be most of the way there. I was lucky enough to have enough high V group duals to match and an exacto blade and the obsession to go farther
I feed both boards with Borbely's super shunts and a good raw supply CLC then LT1085/LT1033 with external LM 329 references (overkill as 317/337 will do fine). I have it going into a SAE MK 1 early 1970s metered preamp chassis (with new meter drivers) with just a Shallco selector and stepped attenuator, new jacks and wiring. The SAE cost $500 to get a classic chassis for mounting the preamp but need room because of the all the regulator and preamp heatsinks when we don't have the original boards which have the better mechanical and electrical layout. SAE collectors may complain.
I feed both boards with Borbely's super shunts and a good raw supply CLC then LT1085/LT1033 with external LM 329 references (overkill as 317/337 will do fine). I have it going into a SAE MK 1 early 1970s metered preamp chassis (with new meter drivers) with just a Shallco selector and stepped attenuator, new jacks and wiring. The SAE cost $500 to get a classic chassis for mounting the preamp but need room because of the all the regulator and preamp heatsinks when we don't have the original boards which have the better mechanical and electrical layout. SAE collectors may complain.
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Genuine Caddock 820 for $1.49?
This may be your only chance for these. eBay #380393895611 gives you a shot at 33r caddock 10%. I ordered a dozen and they split 4@31.0r, 4@31.1r, and 4@31.2r, i.e. they clustered closer to 27r. I am skeptical of the authenticity of the 22r I got from China.
If the caddocks are 4 ohms high will I need to modify nearby resistor values?
This may be your only chance for these. eBay #380393895611 gives you a shot at 33r caddock 10%. I ordered a dozen and they split 4@31.0r, 4@31.1r, and 4@31.2r, i.e. they clustered closer to 27r. I am skeptical of the authenticity of the 22r I got from China.
If the caddocks are 4 ohms high will I need to modify nearby resistor values?
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