C22
Early in the thread I recall reading that some builders left out the 100pF cap at C22, I think to eliminate hiss.
Is there now a consensus that this is left out?
Early in the thread I recall reading that some builders left out the 100pF cap at C22, I think to eliminate hiss.
Is there now a consensus that this is left out?
I used a 4-pin mic connector and left one pin unused. Microphone connectors male or female
You can leave C22 empty unless you need it. If you're using MM or MI, absolutely leave it empty, most phono cables have enough capacitance by themselves.
You can leave C22 empty unless you need it. If you're using MM or MI, absolutely leave it empty, most phono cables have enough capacitance by themselves.
Pass DIY Addict
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To me, part of the concern here is that an XLR jack "appears" to be one that will accept an interconnect or a microphone. Jacking in a mic or IC to a live power supply by accident (because it "looked right") has potential to lead to unnecessary surprises and result in dead equipment or other problems...
I know Pass Labs uses Powercon but I would use neither Powercon nor XLR for a DC PS umbilical cable. I service pro audio equipment and have seen Powercon for AC inlets & lighting etc., which is what they were made for. I'd use something I rarely see used, like a 4-5 pin XLR or a screw-on connector.
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I have used the following modular system for screw-on connectors:
CPC AGR 09S: 9-pin holder for empty housing for pin contacts at reichelt elektronik
CPC SG 09B: 9-pin plug for empty housing for pin contacts at reichelt elektronik
CPC ZE 13: Cable entry with strain relief, size 13 at reichelt elektronik
CPC SK 3: Pin contact for AWG 18-16 at reichelt elektronik
CPC BK 3: Buchsenkontakt fur AWG 18-16 bei reichelt elektronik
This system from TE Connectivity (and similar systems from other manufacturers) can be configured for different numbers of contacts, voltages, currents, etc.
My use is to connect an external power supply to a tubed pre-amp - regulated heaters at up to 3.5 A current, regulated 250 V DC for B+, and a regulated 12V for preamp switching, logic, volume; plus safety earth (PE) on a separate lead to provide a safety ground for the preamp chassis as well.
I had searched for quite some time - went with a system like this because it seems safe, offers enough leads / connections in one plug, and, importantly, can't be mistaken for something else ... 😛
Best regards,
Claas
CPC AGR 09S: 9-pin holder for empty housing for pin contacts at reichelt elektronik
CPC SG 09B: 9-pin plug for empty housing for pin contacts at reichelt elektronik
CPC ZE 13: Cable entry with strain relief, size 13 at reichelt elektronik
CPC SK 3: Pin contact for AWG 18-16 at reichelt elektronik
CPC BK 3: Buchsenkontakt fur AWG 18-16 bei reichelt elektronik
This system from TE Connectivity (and similar systems from other manufacturers) can be configured for different numbers of contacts, voltages, currents, etc.
My use is to connect an external power supply to a tubed pre-amp - regulated heaters at up to 3.5 A current, regulated 250 V DC for B+, and a regulated 12V for preamp switching, logic, volume; plus safety earth (PE) on a separate lead to provide a safety ground for the preamp chassis as well.
I had searched for quite some time - went with a system like this because it seems safe, offers enough leads / connections in one plug, and, importantly, can't be mistaken for something else ... 😛
Best regards,
Claas
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I have used XLR with my Pearl 2 since the beginning with no problems. It only deals with the +/- 35V DC from the PSU with a low current. IIRC the Neutrik XLR's are rated for at least 40V. Female chassis part on the PSU, so you can't touch any live pins (at least not with your fingers), same goes for amp-end of the umbilical, female plug.
^ what he said ... I did the same thing. Works great so far and have had it several years now.
For connectors for power (umbilical and chassis) I used these for my dual mono power supply:
T 3361 001 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
T 3360 001 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
T 3362 000 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
T 3363 000 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
They can’t be confused with signal line connections, and the screw connection is pretty bulletproof.
Terry
T 3361 001 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
T 3360 001 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
T 3362 000 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
T 3363 000 Amphenol Sine Systems Corp | Connectors, Interconnects | DigiKey
They can’t be confused with signal line connections, and the screw connection is pretty bulletproof.
Terry
These connectors look nice. Good for harsh environments. A little pricey though.
MRD-BN04-M17-00 Amphenol Commercial Products | Mouser
MRD-BG04-L13-000 Amphenol Commercial Products | Mouser
MRD-BN04-M17-00 Amphenol Commercial Products | Mouser
MRD-BG04-L13-000 Amphenol Commercial Products | Mouser
Sorry for the obvious question, but I am a beginner. I just received the Pearl 2 boards and would like to start to order parts. In regards to the power supply, can I use the PSU available at the site store or is that not appropriate? I know it might be overkill, but the build guide has a chipamp power supply and they are no longer in business. Also, is there a Mouser BOM readily available? Thanks
Yes you can. I just finished building a powersupply for Pearl 2 using that board. It’s very nicely done and easy to work on. It is also a very flexible board - you can take it as far as you want.
I don’t think there is. But, there are Mouser part numbers for the capacitors and transistors, and you can find more reading this thread as well as the main Pearl 2 discussion thread. You can buy as expensive, or cheap, parts as you desire. I am building my second Pearl 2 [first one went to a friend starting w vinyl]. The first I built with decent but not OTT parts, this one I am building following the Formula 1 construction philosophy.
I just built one using the schematic in the Pearl 2 doc by Wayne. It has minimal parts and is all you need. There is a connection missing from the schematic (rectifier common to circuit ground) that tripped me up, but the folks here pointed it out right away.
What is this about ground to rectifier common? I dont recall doing that, cant quite make out wiring from photo? I copied from build guide, I'll have to open mine up for a peak. It is very quiet.
Russellc
Russellc
Go to the first post and check the 4th photo down and you'll see that there is a hand drawn line showing the rectifier common to ground connection that was missing in the schematic published with the original Pearl 2 article.
Well that squares it. I've kidded myself about a lot of audio stuff, but I'm not that oblivious!
Thanks,
Russellc
Thanks! I will look into this because I am not good at reading a schematic and point to point wiring, although I am going to learn. I also think it might good experience if I want to build one of the First Watt amps when the jfets come back in stock. I'm going to take my time and follow the guide. Having more capacitance with the Universal PSU can't hurt, correct? I'll stick to standard reliable parts this time and when I learn more, I'll splurge on the higher end stuff. I am also going to start the Whammy headphone amp also (maybe I should do that first, seems more straightforward).
Any other advice is always welcome.
I just built one using the schematic in the Pearl 2 doc by Wayne. It has minimal parts and is all you need. There is a connection missing from the schematic (rectifier common to circuit ground) that tripped me up, but the folks here pointed it out right away.
That does look pretty minimal, it might be doable. Is that a 22v Antec in a Galaxy case? Looks great, by the way!