Turning off the Pearl 3 while pre amp and amp are on and in-circuit produces some gawdawful driver whomps. I don't recommend it. Switch to another source, turn off the amp first, anything
May I suggest something I was considering. Reverse the orientation of the top and bottom plates if you can so that the vents are above and below the regulator heatsinks, and so that the signal lead wires to/from the Pearl 3 are covered by solid metal lids.
@ranshdow On a steel covers Modushop Galaxy, there is a bent-in tab that is intended to be placed against the inside of the front panel. This allows the rear panel able to be flush with the chassis top and bottom. If the panels are reversed, that tab will overhang the rear panel which looks awful and may impinge on connectors or printing, etc…
That said, it’s logical to want the solid metal over the inputs and outputs, which is why the Pearl 3 custom chassis has the vents on the “other“ end of the panel. It’s a subtle difference from stock, and was chosen for the exact reason you mention.
That said, it’s logical to want the solid metal over the inputs and outputs, which is why the Pearl 3 custom chassis has the vents on the “other“ end of the panel. It’s a subtle difference from stock, and was chosen for the exact reason you mention.
Your post made me realise that I have been doing it the wrong way round for years in a pair of enclosures for my DIY Bugle... 😕 Top side can be reversed, bottom side not because of the holes drilled into it. Oh well, I actually did not think it looked horrible, and I do not look at the back side anyway...
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from the Faraday Cage aspect perhaps it matters less where the holes are than that there are holes at all?
for heat management hole location manages airflow. this isn't supposed to be critical in this unit -- provided the on-board regulators aren't asked to work too hard. the enclosure doesn't need holes at all, no?
for heat management hole location manages airflow. this isn't supposed to be critical in this unit -- provided the on-board regulators aren't asked to work too hard. the enclosure doesn't need holes at all, no?
Stupid question I’m sure, after ordering the umbilical from Mouser…i ordered the Mogame 2549 as indicated in the BOM, only to realize that the build guide was calling for “at least 3 conductors,” and the 2549 is only 2 conductor. So i ordered the 2534 starquad - 4 conductors - as recommended in this thread back about 30 pages or do. Soooooo…because i have been breathing too many fumes stuffing the boards, my brain is unable to determine the correct protocol for what one does with the 4th conductor.
Please help this poor confused nincompoop….😉
Please help this poor confused nincompoop….😉
It either floats unconnected or connects the chassis grounds together. I think everyone says to try it both ways to see what is quietest in your system.
I searched the thread and found many opinions on grounding schemes. Here's a helpful comment that will also lead you to more grounding discussion: https://www.diyaudio.com/community/threads/pearl-3-burning-amp-2023.404054/post-7543498
I searched the thread and found many opinions on grounding schemes. Here's a helpful comment that will also lead you to more grounding discussion: https://www.diyaudio.com/community/threads/pearl-3-burning-amp-2023.404054/post-7543498
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Thanks Chris…but every time i think i understand grounding, i really don’t understand grounding.
Now quantum physics? That’s another kettle of cats.
Now quantum physics? That’s another kettle of cats.
Hi,
now I will start this project, finally...
I read the 107 pages (great), but I just want to be sure that I understood everything right.
So my short summary - and please correct me if I'm wrong:
Is that right so far?
Many thanks in advance.
now I will start this project, finally...
I read the 107 pages (great), but I just want to be sure that I understood everything right.
So my short summary - and please correct me if I'm wrong:
- J2 is practically a switch between MM/MC; it's for MM when shorted and for MC when opened
- MM should be used with 47k load, so no R-switch on the DIP will be closed
- for MM, the C-switches should/can be used for capacitance adjustment, if needed
- for MC, the load will be adjusted with the R-switches on the DIP
- R-C on the DIP is for high impedance cartridges
Is that right so far?
Many thanks in advance.
Yes. Have power off when changing this.
Correct.
Correct.
Correct.
The RC on the DIP is for the rare high-output MC that oscillates. It's uncommon, but not unheard of.
Correct.
Correct.
Correct.
The RC on the DIP is for the rare high-output MC that oscillates. It's uncommon, but not unheard of.
Just waiting patiently for the diyAudio Store to restock the kits 🙁
Hello All,
Doing the finishing touches on a single Pearl 3 board today.
I am sorting out a few tests to run.
One thing that I did notice was that the majority of the J112 jfets for Q9 were falling out of the bag of 100 at or around a Idss of ~48ma.
For Q9 I tried several values of source resistors, at 15 volts DC supply the source current settled in at ~5ma with ~3.75 volts across the 750R resistor. Next time I will try a PF5102 Jfet with a lower Idss.
Thanks DT
Doing the finishing touches on a single Pearl 3 board today.
I am sorting out a few tests to run.
One thing that I did notice was that the majority of the J112 jfets for Q9 were falling out of the bag of 100 at or around a Idss of ~48ma.
For Q9 I tried several values of source resistors, at 15 volts DC supply the source current settled in at ~5ma with ~3.75 volts across the 750R resistor. Next time I will try a PF5102 Jfet with a lower Idss.
Thanks DT
Another run will be shipped to the fulfillment company shortly.
If anyone is trying to find a quick and easy way to get the recommended Umbilical Canare wire from Amazon, I ordered this and de-soldered the 3 pin XLR connectors to use for custom XLR cables. $19 with free shipping and you just solder on your 4 pin connectors.
https://www.amazon.com/dp/B07VWPPHX6?psc=1&ref=ppx_yo2ov_dt_b_product_details
https://www.amazon.com/dp/B07VWPPHX6?psc=1&ref=ppx_yo2ov_dt_b_product_details