No, generally the 105° are the better ones 🙂 Sometimes Mundorf's 125°C parts have even better specs, but not always.Do you have an example of an 85 ºC rated capacitor that has better specs than its 105 ºC counterpart? I'm curious.
No, generally the 105° are the better ones 🙂 Sometimes Mundorf's 125°C parts have even better specs, but not always.
I’m curious as well. What specs on the Mundorfs are better than for example Panasonic or Nichicon? Examples?
Best,
Anand.
No, generally the 105° are the better ones 🙂 Sometimes Mundorf's 125°C parts have even better specs, but not always.
Would you post the part numbers that you're comparing?
Tom
I really dont remember and don't feel like digging, sorry. Can we just assume that higher temp rating generally associate with better quality and/or specs?
Hi Tom,
I'm stuck. I've replaced U5 and U6.
Measuring voltage from J3 pin 2: I get 0.0V at U4 pin 4, and 31.0V at U4 pin 8.
Just to confirm, I should get +/- 17 even though LM3886 is not onboard, or does that slot on PCB need to be populated in order to get the correct measurement at U4 ?
I'm afraid I see a lot of diodes and desoldering in my future.
What are your thoughts?
I'm stuck. I've replaced U5 and U6.
Measuring voltage from J3 pin 2: I get 0.0V at U4 pin 4, and 31.0V at U4 pin 8.
Just to confirm, I should get +/- 17 even though LM3886 is not onboard, or does that slot on PCB need to be populated in order to get the correct measurement at U4 ?
I'm afraid I see a lot of diodes and desoldering in my future.
What are your thoughts?
Hi Telstar,
No, not always. I generally test the new capacitors I get before installing them with an HP 4263A LCR meter and look at dissipation factor. I test at 1 KHz normally, which is tough on most electrolytic capacitors. But, that is the frequency range they will see in use. Some I test at 10 KHz as well depending on the application.
-Chris
No, not always. I generally test the new capacitors I get before installing them with an HP 4263A LCR meter and look at dissipation factor. I test at 1 KHz normally, which is tough on most electrolytic capacitors. But, that is the frequency range they will see in use. Some I test at 10 KHz as well depending on the application.
-Chris
Linux. Changing the world one configuration file at a time. 😀 Sorry. I couldn't resist. Last I ran linux, it severely tested my patience.
Now, regarding the point you're making: Yep. An old laptop running some DSP software is a valid approach. I've used Reaper with reaEQ in the past. that worked pretty well, though the learning curve is a bit steeper than that of a "boxed" solution.
Tom
16k taps per channel @ 48khz with 12 channels running and the ability to add more is nice 😉 About 24ms delay with the current config. I use FIR Designer for building the filters. I wrote some scripts to toggle out filters, so can compare back to back with under 1/10th of a second of downtime, so that's nice when testing changes.
Using digital input vs analog input on sound cards make a difference. When people refer to the MiniDSP, it would be more informing to know whether you are you are using and measuring it.
I just got a MiniDSP 2x4HD, hope to test the potential. I will be using both analog and digital interfaces adding a Bluetooth receiver to the analog side.
I just got a MiniDSP 2x4HD, hope to test the potential. I will be using both analog and digital interfaces adding a Bluetooth receiver to the analog side.
I really dont remember and don't feel like digging, sorry. Can we just assume that higher temp rating generally associate with better quality and/or specs?
Generally, for caps used in loudspeaker passive crossovers, I find in general, for the same brand film capacitors, the higher voltage rating are generally better. But it also depends on the actual film material involved as well. Lots of the specs are geared towards higher frequency application out of the audio range, so may not be so relevant in the audio range.
However, it seems that temperature variation effect on spec variation would be an important aspect as with resistors.
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Can we just assume that higher temp rating generally associate with better quality and/or specs?
Not in my opinion. I would rather base such claims on science and facts than heresy.
Tom
Measuring voltage from J3 pin 2: I get 0.0V at U4 pin 4, and 31.0V at U4 pin 8.
Hmmm... So when you had the polarity reversed on the power input, did you have any of the ICs U1, U3, or U4 installed?
Just to confirm, I should get +/- 17 even though LM3886 is not onboard
Correct. U5/U6 are completely independent of the LM3886.
I'm afraid I see a lot of diodes and desoldering in my future.
It kinda has that look. Let's be methodical about it, though.
1) Cut diodes D2, D3, D4, and D5 off the board. Test ±17 V.
2) If no ±17 V, cut diodes D9, D10, D11, and D12. Test ±17 V.
3) If still no ±17 V, replace U5, U6 (yes, I know you just did).
4) If still no ±17 V, get a new board. I have three left... 😉
I bet the ±17 V will come to life in Step 1). Replace what you cut off. If you make it through step 2), I'd replace C26, C27, C30, C31 as well.
Tom
Hi Telstar,
No, not always. I generally test the new capacitors I get before installing them with an HP 4263A LCR meter and look at dissipation factor. I test at 1 KHz normally, which is tough on most electrolytic capacitors. But, that is the frequency range they will see in use. Some I test at 10 KHz as well depending on the application.
-Chris
What is the objective? Is it to ensure the component matches up to its spec'd values?
I generally test the new capacitors I get before installing them with an HP 4263A LCR meter and look at dissipation factor. I test at 1 KHz normally, which is tough on most electrolytic capacitors. But, that is the frequency range they will see in use. Some I test at 10 KHz as well depending on the application.
-Chris
Nice to see that you are still around!
I have one Rev. 1.01 boards left in my Modulus project box. I must have sold an odd number of them and ended up with a spare. Toss me an email if you're interested in buying.
I'm down to seven (7) of the Rev. 2.2 boards. Those who are sitting on a stash of LME49710s they'd like to use should buy now as Rev. 2.3 will use the LME49720. Aside from that, Rev. 2.3 will not feature any significant changes.
Tom
Have any rev2.1 boards? I have a round can version of LME49710 on the shelf.
Nope. I have one MOD86 Rev. 1.01 board left. That won't do you any good.
You can make the TO-99 can work on a DIP-8 footprint, though. Like this:
Just beware of that pesky Pin 8 vs Pin 1 issue when dealing with TO-99 cans. The can has Pin 8 marked!
Tom
You can make the TO-99 can work on a DIP-8 footprint, though. Like this:
An externally hosted image should be here but it was not working when we last tested it.
Just beware of that pesky Pin 8 vs Pin 1 issue when dealing with TO-99 cans. The can has Pin 8 marked!
Tom
Hi Brian,
It doesn't take very long to do, and I generally like to know what I'm installing. One bad new component can cause days of troubleshooting some times. It's not like I'm going through hundreds of capacitors.
Much of the upgrade work I do can depend on matched parts, so since I'm already looking at the values, a quick look to the other display tells me a lot about what I'm installing. I have run into bad mica capacitors and polypropylene capacitors with high dissipation. Good thing I checked. I will often check incoming capacitors to ensure the parts are good, and are what I ordered. Keep in mind I'm ordering parts through the proper distribution chain.
-Chris
It doesn't take very long to do, and I generally like to know what I'm installing. One bad new component can cause days of troubleshooting some times. It's not like I'm going through hundreds of capacitors.
Much of the upgrade work I do can depend on matched parts, so since I'm already looking at the values, a quick look to the other display tells me a lot about what I'm installing. I have run into bad mica capacitors and polypropylene capacitors with high dissipation. Good thing I checked. I will often check incoming capacitors to ensure the parts are good, and are what I ordered. Keep in mind I'm ordering parts through the proper distribution chain.
-Chris
Thanks Chris. I was asking because I wasn't sure if you were trying to confirm the specs or if there was some other measurement you were trying to discern that isn't on the published spec sheets.
I have square ones too (got four extras just before I got 2.1 boards,... but you changed to the TO-99 can before I got boards) LOL.
So cutting D2, D3, D4 and D5 off the board, I still got 0.00 and 30
After cutting D9, D10, D12 and D12, I got 0.0 and 16.8V. (Better)
I guess I need to replace U5 and U6 again. Or is it only one of those now? Pin 4 is where I still get 0.0. (And replace diodes and the 4 caps you mention)
Is the performance and sound output of 2.2 identical to 2.1 ? Might be easier to start over than to do so much desoldering. But obviously, the left and right sound output must match.
So cutting D2, D3, D4 and D5 off the board, I still got 0.00 and 30
After cutting D9, D10, D12 and D12, I got 0.0 and 16.8V. (Better)
I guess I need to replace U5 and U6 again. Or is it only one of those now? Pin 4 is where I still get 0.0. (And replace diodes and the 4 caps you mention)
Is the performance and sound output of 2.2 identical to 2.1 ? Might be easier to start over than to do so much desoldering. But obviously, the left and right sound output must match.
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