Guys-
I am having a bit of trouble doing my initial IPS tests. Have applied a 9.1K parallel resistor across R17 and am feeding the boards with about +30/0/-30 into the V+/G1G2/V- pins. When I measure the voltage on the NFB header pin relative to ground, it is always about 30V. This does not seem right. I wonder if I should be measuring from TMC/R21B (J1) to ground instead. R21B/TMC seems to have no connectivity to the NFB header pin.
My dad used to say that "patience is its own reward". 🙂
Thanks!
I am having a bit of trouble doing my initial IPS tests. Have applied a 9.1K parallel resistor across R17 and am feeding the boards with about +30/0/-30 into the V+/G1G2/V- pins. When I measure the voltage on the NFB header pin relative to ground, it is always about 30V. This does not seem right. I wonder if I should be measuring from TMC/R21B (J1) to ground instead. R21B/TMC seems to have no connectivity to the NFB header pin.
My dad used to say that "patience is its own reward". 🙂
Thanks!
Is it Christmas in October???
Got these bad boys today! They look awesome!
Thanks to @ostripper @stuartmp @fireanimal
Not gonna lie. I am extremely intimidated by these boards. I have some homework to get the BOM just right on these. Thanks again!
Got these bad boys today! They look awesome!
Thanks to @ostripper @stuartmp @fireanimal
Not gonna lie. I am extremely intimidated by these boards. I have some homework to get the BOM just right on these. Thanks again!
Don’t be, took my time, took me a couple week to do the first boards just doing a few components a night and checking everthing as I went, then my second set took me a little over a day. Not including chassis install and wiring obv.
But don’t rush, it’s worth it in the end.
I bet @fireanimal does them in a couple hours.
But don’t rush, it’s worth it in the end.
I bet @fireanimal does them in a couple hours.
Ooh, I wish I had seen this before I left for the show.
I did see the amps, but didn't get to talk with Neil. Both amps looked beautiful. The craftsmanship is exemplary. Same for the speakers.
Good show too.
Thanks man. That is the plan. This project is a bit more advanced than my current skill level. I am just nervous that I am going to mess something up.
Don't worry we are here to support you. Read the build guide through before you go started. Ask questions if you need to.
Watching @danieljw Video series will also help you get up to speed.
My build album photos are there for a reference to if you need to double check anything.
My advice is focus on one thing at a time, don't try and order every part for the entire amplifier and build it all at once. You'll find it easier if you complete one board at a time a what you learn on the first on you'll apply to the second one....
Good luck 👍
@Jacruzer787 - FWIW - I'm in the same boat. I have waited and waited (since GB1) to see more successful builds. I've watched as people have asked questions while simultaneously the build guide has been meticulously updated to cover what I'd consider all eventualities / questions / options.
I've got a few more parts to order and some planning to do re: heatsinks (I planned on both types (3 and 4) boards not requiring any extra holes in a UMS heatsink when it was announced, and I was incorrect. I bought the boards before the guide and images of the boards were posted. I'll likely build the '3' first and then move to the '4'. I need to refine my drilling and tapping.
From what I can see, the community of support around this project is second-to-none. I plan on asking questions as I go if they arise. With the build guide, I don't see too many coming up, but the folks in this thread seem extremely patient.
Let's do it!
I've got a few more parts to order and some planning to do re: heatsinks (I planned on both types (3 and 4) boards not requiring any extra holes in a UMS heatsink when it was announced, and I was incorrect. I bought the boards before the guide and images of the boards were posted. I'll likely build the '3' first and then move to the '4'. I need to refine my drilling and tapping.
From what I can see, the community of support around this project is second-to-none. I plan on asking questions as I go if they arise. With the build guide, I don't see too many coming up, but the folks in this thread seem extremely patient.
Let's do it!
I have a question about the drivers for the output boards;
The drivers are the only components I still need for this build but a question has come up so here's the info I'm sure others will ask before replying. I'm building an EF3-3 build utilizing the MJL4281/4302 outputs with 70 0r 71V rails. The drivers I had planned on were the MJE15032/15033 combo but alas, they're a no stock at mouser and digikey. The 15030/15031 and the 15034/15035 are available but I don't know which parameters are the most important to stay with for the outputs I've chosen (and purchased). I see that Arrow does have the 15032/15033 drivers but at $22.00 shipping for 4 transistors from the NL.
Any advice on this?
The drivers are the only components I still need for this build but a question has come up so here's the info I'm sure others will ask before replying. I'm building an EF3-3 build utilizing the MJL4281/4302 outputs with 70 0r 71V rails. The drivers I had planned on were the MJE15032/15033 combo but alas, they're a no stock at mouser and digikey. The 15030/15031 and the 15034/15035 are available but I don't know which parameters are the most important to stay with for the outputs I've chosen (and purchased). I see that Arrow does have the 15032/15033 drivers but at $22.00 shipping for 4 transistors from the NL.
Any advice on this?
@MilkyChance
Just checked and they're backordered as well. That's why I asked about parameter specs.
Just checked and they're backordered as well. That's why I asked about parameter specs.
Forgot to ask about another concern... When using the MJL4281/4302 outputs with 71V rails will 4U heatsinks be large enough for an EF3-3 build at that voltage?
Someone more knowledgeable than me might chime in to correct me, but I don't think you can substitute either of those for the MJE15032/33, mainly due to the current requirements.
Regarding the 4U - I have a EF3-3 using 70V rails in a 4U chassis and it runs warm, but not hot and has been fine for a few months now, running 4-5 hours a day.
Regarding the 4U - I have a EF3-3 using 70V rails in a 4U chassis and it runs warm, but not hot and has been fine for a few months now, running 4-5 hours a day.
i m use these 15034 15035 no problem.....
Amplifier drone hahaha ...like he said my friend Thimios
The third image is out of the amplifier's manufacturing specifications ( extra heatsink)......it is from my measurements....
Τhe amplifier every day now plays music very loud without protections (I take my risks) But his measurements have made me trust him from the beginning.
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I am also going to use 15034/35. What I have understood the higher current capabilities with 15032/33 is usually not necessary in driver stages, but I can be wrong and there can also be some other advantages with 15032/33 as drivers that I don't know of.