I've found that modern LED's can be blindingly bright on even a few hundred microamps. It might be worth experimenting a little with a 9 volt battery +LED + resistor to see what brightness you actually want.
I was thinking of mounting the resistor against the, heatsink like, side panel. It would be close to the LED, such that the LED cathode and resistor wires will just overlap for a little twist and soldering and the wire soldered to the other end of the resistor will go to V-. The anode will have a wire running to the power-86 chassis grounding screw.
Thanks, and sorry but here is the last question.
By "chassis mounted resistor" is there a special resistor design? I was just thinking of making a small copper clip with a small mounting hole. It would screw onto the side panel and wrap half way round the resistor to hold it against the heatsink panel.
Thanks,
henry
Thanks, and sorry but here is the last question.
By "chassis mounted resistor" is there a special resistor design? I was just thinking of making a small copper clip with a small mounting hole. It would screw onto the side panel and wrap half way round the resistor to hold it against the heatsink panel.
Thanks,
henry
Chassis mount resistors: TE HSA series: Mouser P/N: 279-HSA255K6J
Or get a 5 W Ohmite resistor in a rectangular package and make a mounting clip. Mouser P/N: 588-TUM3J5K6E. I suggest the 5 W type because it would be easy to machine a bracket for. Also, in some of the cylindrical resistors, the resistive element is covered by a thin layer of enamel that a bracket could easily wear through and short the resistor to the heat sink. With the rectangular resistors, the resistive element is enclosed in a "sandbox" and well protected.
If you use any other LED than the HLMP-D101, I suggest following Mooly's advice and getting the brightness dialled in using a battery and a series resistor. Once you know which current you'd like, you can figure the proper resistor for 30 V operation and go from there.
The HLMP-D101 is a classic deep red (637 nm), which I happen to like.
Tom
Or get a 5 W Ohmite resistor in a rectangular package and make a mounting clip. Mouser P/N: 588-TUM3J5K6E. I suggest the 5 W type because it would be easy to machine a bracket for. Also, in some of the cylindrical resistors, the resistive element is covered by a thin layer of enamel that a bracket could easily wear through and short the resistor to the heat sink. With the rectangular resistors, the resistive element is enclosed in a "sandbox" and well protected.
If you use any other LED than the HLMP-D101, I suggest following Mooly's advice and getting the brightness dialled in using a battery and a series resistor. Once you know which current you'd like, you can figure the proper resistor for 30 V operation and go from there.
The HLMP-D101 is a classic deep red (637 nm), which I happen to like.
Tom
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Thanks Tom,
I just listened to Mahler's 5th. I consider it one of the best tests of dynamics, sound stage, speed and separation and clarity of instruments. The opening trumpet's position in the orchestra is well know. Your Mod86 is the best I've heard. It sounded quite good on my B&W N803s, pre Mod86. But on my heavily modifed $500 Sound Dynamics 300Ti spkrs your amp is the best I've heard. The piece has incredibly complex tutti sections and they came through incredibly unscathed.
I've brought this CD to my friends very high end store and played it on +$100K system and a few others in the $50k range and have always preferred my system and that was before the Mod86. Some of his techs have heard my system, pre Mod86, and felt like I do. They need to hear your amp.
I just listened to Mahler's 5th. I consider it one of the best tests of dynamics, sound stage, speed and separation and clarity of instruments. The opening trumpet's position in the orchestra is well know. Your Mod86 is the best I've heard. It sounded quite good on my B&W N803s, pre Mod86. But on my heavily modifed $500 Sound Dynamics 300Ti spkrs your amp is the best I've heard. The piece has incredibly complex tutti sections and they came through incredibly unscathed.
I've brought this CD to my friends very high end store and played it on +$100K system and a few others in the $50k range and have always preferred my system and that was before the Mod86. Some of his techs have heard my system, pre Mod86, and felt like I do. They need to hear your amp.
Now it's time you parade around town with your Mod86 and let the amp strut it's stuff. Spread the word and redirect them to Neurochrome Audio: High performance DIY audio circuits. 😎
Best,
Anand.
I'm a promoter of Tom's stuff for sure.
Right now an Aragon 18k MKII is connected to the Mod86. Tomorrow the 2008 Audible Illusions M3A with NOS tubes will be connected to the mod86.
I'm actually considering selling my Aragon 8008BB, Adcom GFA 5400 and McCormack Deluxe Edtion DNA0.5. The McCormack is quite good sounding and the Aragon is also very good with tons of power. Any body interested? I'm in Ct and they are still connected so they can be heard.
Right now an Aragon 18k MKII is connected to the Mod86. Tomorrow the 2008 Audible Illusions M3A with NOS tubes will be connected to the mod86.
I'm actually considering selling my Aragon 8008BB, Adcom GFA 5400 and McCormack Deluxe Edtion DNA0.5. The McCormack is quite good sounding and the Aragon is also very good with tons of power. Any body interested? I'm in Ct and they are still connected so they can be heard.
Bartok's Miraculous Mandarin is up next, for tomorrow, after the AI M3A is connected.
Tonight will be a lot of Keith Jarret and Charles Lloyd.
Tonight will be a lot of Keith Jarret and Charles Lloyd.
Chassis mount resistors
I just realized I know what you meant. I have a bunch of chassis mount resistors. I've used them on heatsinks in my outboard xovers. One of the aluminum cased, fined resistors will look cool, but no one will ever see it...so what. I get to use some of my old stock. I need a kick in the head to get thinking. Sh*t, old age sucks.
Tom,
Your a genius. I've been listening to Brad Meldhau and it's fantastic. I've got a very good piano in an adjacent room and I hit a few keys to get a baseline. Your amp is closer than anything I've owned. There is no strain or the oft used term "strenuous or fatiguing sound".
FWIW I've been a musician for probably many more years than your age.
Somebody please buy my other amps. I will be getting two more Mod86 amps.
Your a genius. I've been listening to Brad Meldhau and it's fantastic. I've got a very good piano in an adjacent room and I hit a few keys to get a baseline. Your amp is closer than anything I've owned. There is no strain or the oft used term "strenuous or fatiguing sound".
FWIW I've been a musician for probably many more years than your age.
Somebody please buy my other amps. I will be getting two more Mod86 amps.
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One last observation, for now. I've read a few say bass is not a strong point. I totally disagree. My speakers are truly decoupled from the wood floor yet when appropriate the bass vibrates the whole room in a very, strong, natural way. Oh and the room is not really small; 14 W x 18 L x 8 1/2 H.
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No worries. Sometimes it's hard to see the forest for the trees.
Thank you very much. I'm glad you like it.
That's possible. I was born seven years after the Toronto Maple Leafs last won the Stanley Cup. You do the math... 🙂
That's a pretty strong endorsement. Thanks! You know where to find me. It generally doesn't take me more than a couple of days to a week to build some modules for you. Now you know how to build the amp. All you have to do is to make a 1:1 copy.
Tom
I've learned my lesson and had some of my extraneous posts removed and going to request more be deleted...no more chit chat.
So now, I hope, a valid question. I used kester 63/37 1.1% flux. My thought is it all went up in smoke. They look clean. The Metcal really got things hot very quickly. Does anyone think I should clean the joints with acetone?
So now, I hope, a valid question. I used kester 63/37 1.1% flux. My thought is it all went up in smoke. They look clean. The Metcal really got things hot very quickly. Does anyone think I should clean the joints with acetone?
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Your throwing that question out to the wider audience 🙂
Well I tend to clean the soldered side of PCB's with isopropyl alcohol to remove all flux and then (look away now Tom), I use a conformal coating by Electrolube but I don't spray it on, I spray some into a container and brush it on, and then air dry at moderate temperature. That gives the board a super clean and glossy look.
ELECTROLUBE - HPA200H - CONFORMAL COATING,HPA, 200ML | CPC UK
If you used solder with no-clean flux, you don't have to do anything.
If you used solder with rosin flux, you can leave it alone, but cleaning it off with a flux remover (available in a spray can - MG Flux Remover or Chemtronics Flux-OFF) would be appropriate.
If you used water solder with water soluble flux you HAVE TO clean it off.
Get the least aggressive flux remover. I.e. go for the "regular" rather than the "heavy duty". The regular is generally safe on plastics, whereas the heavy duty "may dissolve some plastics". Read and follow the instructions on the can.
Some flux cleaners leave a dull residue. You can remove this with a DI or distilled water rinse. Do make sure that all water has been dried up or evaporated before powering up the amp.
I cleaned the boards with Flux-OFF and a water rinse before I shipped them to you so there should be nothing to clean there.
Tom
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Denatured alcohol followed by a good detergent based wash is what works for me. Just my 2 cent solution.
Since this is a build thread I will post my impressions of the sound of the finished product in the Mgf thread for the mod86. I will be requesting more of my bullish!t be deleted from this thread.
Henry, don't worry about it. Just move forward. If you start removing your posts, the responses will appear out of context, so more cleanup will be needed. Just do your best to stay on topic in the future and all will be right with the world.
Tom
Tom
Henry, it would not be fair on all the contributors to the thread to simply delete all your posts, not least Tom who has put so much into answering all the questions. As such your formal request for all your diyAudio posting history to be deleted can not be entertained.
It is only under exceptional circumstances that a post would be deleted (safety grounds, personal info on display etc).
You've done a great job building this amp, and the fact you've done it so successfully will I'm sure serve as encouragement for others to have a go.