I wouldn't judge mine as being "laid-back". What turntable and cartridge are you using with it? Is the gain the standard 55dB or higher? Brilliance and air might be due to more high end on your previous phono pre (which one is that?), which could be due to different loading.
I have a Rega P6 (new edition) with Neo PSU. Bought it together as a kit with the Rega Ania MC cart and Fono MC preamp.
This combo has been way too bright for my liking, so I switched the cart to an Audio Technica AT33EV. This cart has more bottom end and not so dominant heights.
I may switch to the Ania MC and try it out again...
Running currently with 60dB gain, output of cart is 300uV (300 Ohm on R14) and loading of 220 Ohm (should be at least 100 Ohm for both my carts)
What cart are you using?
This combo has been way too bright for my liking, so I switched the cart to an Audio Technica AT33EV. This cart has more bottom end and not so dominant heights.
I may switch to the Ania MC and try it out again...
Running currently with 60dB gain, output of cart is 300uV (300 Ohm on R14) and loading of 220 Ohm (should be at least 100 Ohm for both my carts)
What cart are you using?
Comparable to you. Currently Rega P3 with Tangospinner subplatter and AT33PTG/II. Pearl at approx 57 dB gain (777 Ohm on R14), loading is currently 332 Ohm. I will try 100, 150 and 220 as well. This is not the table that the Pearl is meant for, however. That is a Thorens TD320 MkII with a Benz Wood SL cartridge. I'm still working on the setup of that cartridge. I just got the Pearl up and working yesterday (rebuild on official pcb's, until now I had it built on perfboard).
I'd play with loading first... "Laidback" and "not detailed" are not attributes people usually assign to the Pearl II. 🙂
De Rega Phono has much higher capacitance (1000/4300 pF) although this probably does not have much effect om mc cartridges. Also check the values of the components in the RIAA section for possible errors.
220 Ohm for the AT33 should be fine, but I would try 100 and 470 as well to get an idea.
I don't know if the sound characteristic of the Pearl changes with gain, with R14 = 300 Ohm the Pearl has 65dB gain. I would try a lower gain (500-750 Ohm for R14) and see if that makes a difference.
220 Ohm for the AT33 should be fine, but I would try 100 and 470 as well to get an idea.
I don't know if the sound characteristic of the Pearl changes with gain, with R14 = 300 Ohm the Pearl has 65dB gain. I would try a lower gain (500-750 Ohm for R14) and see if that makes a difference.
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I'd play with capacitance at C22 and resistance at R20 in accord with the data sheet for your cartridge. If you can, I'd also measure the capacitance of your tonearm wiring in conjunction with the RCA leadouts for your table (remove cartridge first). Capacitance loading presented to the cartridge is the total capacitance of your tonearm, RCA cables, plus whatever is mounted in C22.
I know that the Ania MC cart is recommended 1000pF. Might need to play with the values. Or maybe Pearl needs some burn in time...
C22? Maybe you mean C15?
I just found two 330pF mica capacitors laying around and put them for experiment in C15. The sound is started to open up, no so dull as before. Not quite there, but much better now.
I see now C22 is the cart loading. Ah... need to unmount the boards to solder out C22 in order to try new values
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Ok, I'm one step further. I left out C7 as suggested somewhere in this thread. So putting in C7 made a huge improvement in sound... The problem is, that on my left channel, if I want to adjust 0 offset, it jumps from 0V right to -23V with almost no sound coming from this channel.
I will then have to try out putting a capacitor between R14 and ground as suggested
I will then have to try out putting a capacitor between R14 and ground as suggested
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C7 and C15 are both open on my board. The following are notes that I recorded about these two caps:
For C7, Wayne recommended leaving this out. It was intended to reduce potential ultrasonic oscillation in Q2, but may cause hiss when installed.
For C15, Jackinnj posted that it was for stability in the feedback loop. F= 1/(2pi*100kΩ*5pF)=2,000,000. Adding more capacitance lowers the frequency at which the attenuation occurs and installed 5pF in this position.
It might be a little late now, but when I built my Pearl II, I installed sockets on C22 and R20 in order to be able to play with cartridge loading. Might be useful for you...
For C7, Wayne recommended leaving this out. It was intended to reduce potential ultrasonic oscillation in Q2, but may cause hiss when installed.
For C15, Jackinnj posted that it was for stability in the feedback loop. F= 1/(2pi*100kΩ*5pF)=2,000,000. Adding more capacitance lowers the frequency at which the attenuation occurs and installed 5pF in this position.
It might be a little late now, but when I built my Pearl II, I installed sockets on C22 and R20 in order to be able to play with cartridge loading. Might be useful for you...
Attachments
C7 caused oscillations in some builds, so be careful with that. Offset in the left channel sounds like something is wrong. Check every connection on that one. Q2 might be faulty, very easy to blow one, happened to many, including myself.
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Thanks Eric. I don't think that the cart loading resistor and capacitance will give much improvement or change overall as I have experienced with other phono pre's. It's basically just slight tweaking.
So maybe I do have some oscillations on Q2?? Didn't notice any added hiss whatsoever.
It is really weired. If I adjust P1 from positive voltage, it goes to 0V and then just suddenly jumps straight to -23V. I go back and it jumps from approx. -22V to 4 or 5V...
Maybe my Q4 is faulty?
Do you have the capacitor after R14 mod?
So maybe I do have some oscillations on Q2?? Didn't notice any added hiss whatsoever.
It is really weired. If I adjust P1 from positive voltage, it goes to 0V and then just suddenly jumps straight to -23V. I go back and it jumps from approx. -22V to 4 or 5V...
Maybe my Q4 is faulty?
Do you have the capacitor after R14 mod?
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C22 definitely impacts treble performance from your cartridge - it did for me and playing around with different values made pretty clear differences in the sound.
Yes, I did make this mod. Not sure about the offset problem you are describing, though. I don't have any direct experience with this problem, perhaps others will have better insights than I do...
Yes, I did make this mod. Not sure about the offset problem you are describing, though. I don't have any direct experience with this problem, perhaps others will have better insights than I do...
It could be indeed Q4. I received only 5 2SK170BL and a J74 instead of 6 from the passdiy store. I used one new 7,4mA IDSS laying around for the Q4 position for one channel. Just don't know which one it was 🙂 without C7 i can adjust offset on both channels with some +-400mV
In my most recent build on the official boards I left the capacitor/R14 mod out. Right now the offset is nice and only moving within a few millivolts. But I have to monitor its behaviour a bit more. Is it still stable after a few hours? I did the capacitor mod on a previous build (100 uF Elna Silmic II) and it worked very well. But offset jumping to -23V sounds like something else is wrong that needs checking first.
My jfets were around 6.4-6.5 mA idss. Don't know if putting a 7.4mA for Q4 would really cause these kind of effects.
I may swap Q4 with Q5 and check the offset. Will have to order some Elna silmics anyway
Do you have an MM cart? I mostly read that capacitance doesn't matter much for MC's because of their low inductance. For MM's it most certainly matters.
Is the reason the Ania wants to be loaded at 1000pf a coil inductance issue. I thought this was only a "thing" with higher output MC's. Anyone know?
jeff
jeff
The Ania MC came out together with the new Fono MC preamp from Rega. This preamp has two capacitance settings - 1000pF and 4300pF. So I think the 1000pF recommendation is a marketing thing to show that the new pre perfectly suits the new cart. Didn't hear any difference with either settings whatsoever