Pearl 2 build
Hi,
I currently have a Rotel RC-870BX preamp + Systemdek turntable with an MC system (Skala).
As my Rotel sometimes seems to loose a channel and there's moreover some ground-loop humming and I want to step up my equipment, I currently consider to build to a Pearl 2 phono preamp.
I see that it is possible to buy the PCB with matching JFETS from this site:
PassDiy
However, before buying and assembling, I have the following questions:
- What experiences do you have with the Pearl 2? Would you recommend it?
- Is building the Pearl 2 very complex? I recently built the DDDAC from Doede Doema, so I do have some experience with soldering and I do have measurement equipment.
- Are specific parts recommended, e.g. Vishay resistors, Mundorf capacitors etc. or some other modifications to the design?
- What power supply do people use, are there any recommendations?
- Any idea where to get a case and what I should keep in mind?
Any help is appreciated,
Best wishes,
Hermann
Hi,
I currently have a Rotel RC-870BX preamp + Systemdek turntable with an MC system (Skala).
As my Rotel sometimes seems to loose a channel and there's moreover some ground-loop humming and I want to step up my equipment, I currently consider to build to a Pearl 2 phono preamp.
I see that it is possible to buy the PCB with matching JFETS from this site:
PassDiy
However, before buying and assembling, I have the following questions:
- What experiences do you have with the Pearl 2? Would you recommend it?
- Is building the Pearl 2 very complex? I recently built the DDDAC from Doede Doema, so I do have some experience with soldering and I do have measurement equipment.
- Are specific parts recommended, e.g. Vishay resistors, Mundorf capacitors etc. or some other modifications to the design?
- What power supply do people use, are there any recommendations?
- Any idea where to get a case and what I should keep in mind?
Any help is appreciated,
Best wishes,
Hermann
Hi Hermann, the Pearl 2 is one of the best phono preamps out there. Building it is straightforward, just soldering the components in. There is a BOM available and you can use the parts of your choosing. There is a simply power supply schematic in the Pearl 2 document, but again you can use what you want that has +-32DVC. Cases are sold on the DIYAudio store, link is at the top of the page. Good luck!
Good Morning,
I decided not to build the Pearl 2. I went with the Hagerman Bugle 2 kit. It was a much simpler build and the quality was very good. Unfortunately, they no longer offer the complete kit, only the PC board for $39.00, free shipping. There is a list of parts needed and most can be sourced from Mouser. They do offer a completed Bugle 3 for $189.00. Main difference is instead of swapping out resistors to change loading & gain, there are small two way switches. The owner of the site is very responsive and one generally gets an answer in 24 hours or less. They are located in Hawaii.
Link: Phono – Hagerman Audio Labs
I decided not to build the Pearl 2. I went with the Hagerman Bugle 2 kit. It was a much simpler build and the quality was very good. Unfortunately, they no longer offer the complete kit, only the PC board for $39.00, free shipping. There is a list of parts needed and most can be sourced from Mouser. They do offer a completed Bugle 3 for $189.00. Main difference is instead of swapping out resistors to change loading & gain, there are small two way switches. The owner of the site is very responsive and one generally gets an answer in 24 hours or less. They are located in Hawaii.
Link: Phono – Hagerman Audio Labs
I am still loving the pearl two but have a question as I changed both my table and my cartridge. I restored a TD-124 and am using a Denon DL-103 cart. I replaced the 47k resistor with a 100 resistor but when I measure across the inputs I see a load of 28 or so ohms. I have the zobel installed and am wondering if this is what is causing it? I would think in parallel the resistance would still be higher than 28 given the zobel resistor is 680 ohms. Any guidance? Anyone else using the 103 with the pearl 2?
The advantage of the Pearl over an op-amp based phono pre with passive compensation network is that you may run out of overhead margin. The second is that you give away a lot in terms of noise vis a vis the Pearl. 4 matched K170's noise will be ~800pV/RtHz, and there is virtually no current noise.
Finally got around to finishing up my Pearl 2. Everything seems to be ok (after a silly mistake), but I seem to run out of range on P1 when trying to adjust for 0v offset. I do have the cap in series with R14, but short it out for the measurement. Both channels wind up with around -70-80mv offset. Very stable at that point, but it won't go any lower. This is obtained when the pot is turned completely clockwise. Should I just fire it up and forget about it, or should I change the value of R6 and if so...to what? My boards are stacked, so I'd rather not put the top one on only to have to remove it! I'd like to be pretty sure that I'm good to go.
Hallo liebe Community, ich hätte gerne ein Problem! Wie viele hier habe auch ich bei meinem Oearl Two eine zu geringe Spannung an Q3. Vorgeschlagene Maßnahmen wie: -C7 entfernt; -R21-R24 auf 20 Ohm erhöht; -R10 22kOhm parallel gelötet und die Spannungen sind: vE-6,9V; vB-7,6 V; vK-7,7V. Das bedeutet, dass Q3 offen ist, wie ich herausgefunden habe. Ein weiterer parallel geschalteter 47kOhm-Widerstand brach mit folgendem Ergebnis: vE-6,3V; vB-7,0 V; vK-7,7V. Soll ich mit dem Ergebnis zufrieden sein oder soll ich noch an R21-R24 und R10 basteln? Bei einem Hörtest sieht es momentan schlecht aus, alles zerlegt ist mir viel zu gefährlich. Vielen Dank
@dezibaby
Hallo und Grüße!
Dies ist ein englischsprachiges Forum, können Sie bitte auf Englisch posten? Die Verwendung webbasierter Übersetzungen wie Google Translate ist zulässig. Vielen Dank.
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Hello and greetings!
This is a english-language forum, can you please post in english? The use of web-based translation such as Google Translate is acceptable. Thank you.
Hallo und Grüße!
Dies ist ein englischsprachiges Forum, können Sie bitte auf Englisch posten? Die Verwendung webbasierter Übersetzungen wie Google Translate ist zulässig. Vielen Dank.
~~~
Hello and greetings!
This is a english-language forum, can you please post in english? The use of web-based translation such as Google Translate is acceptable. Thank you.
Hello dear community, I would like to have a problem! Like many here, I have too little voltage at Q3 on my Oearl Two. Suggested actions such as: -C7 removed; -R21-R24 increased to 20 ohms; -R10 22kOhm soldered in parallel and the voltages are: vE-6.9V; vB-7.6V; vK-7.7V. That means Q3 is open as I found out. Another 47kOhm resistor connected in parallel broke with the following result: vE-6.3V; vB-7.0V; vK-7.7V. Should I be satisfied with the result or should I still tinker with R21-R24 and R10? In a hearing test, it looks bad at the moment, everything disassembled is far too dangerous for me. Many Thanks
My Pearl 2 is completed. Performs above my expectations. No hum whatsoever even with pre-amp gain at full volume, only a bit of white / pink noise a little bubly. With good recordings it produces a great soundstage with good depth information. And rhythmic information gets throug so well over the frequency span. Very happy I am. 
Built a wooden box for it, and built a steel box inside the wooden box for proper screening, both magnetic and electric. That worked real well. The wood also dampens all tendencies for steel boxes to resonate. Favorite listening setup is playing from a Woodpecker with an Allnic rose pu into my Whammy and through my ZMF's. Bliss. Does also sound very good through my speakers..
Built a wooden box for it, and built a steel box inside the wooden box for proper screening, both magnetic and electric. That worked real well. The wood also dampens all tendencies for steel boxes to resonate. Favorite listening setup is playing from a Woodpecker with an Allnic rose pu into my Whammy and through my ZMF's. Bliss. Does also sound very good through my speakers..Attachments
