Neverless it is good practice to twist the positive and return wires together to minimize inductive noise pickup.
The mounting holes are isolated from the ground plane / circuti common - a deliberate decision - so the standoffs can be metal or not it doesn't matter. The boards are connected to the chassis explicitly via the GND pad.
Just finished Emerald project
First, I like to say thank you to Richard for providing me such a good phono stage. I have tried to build MC phono stage several times but never succeeded. However, at this time I can say that this project was successfully completed- "NO HUM" at all so far.
I received the boards from Richard in the beginning of May, and ordered all necessary parts. I did not use all day for this project but worked two hours pretty much everyday for two weeks and finally put them all together.
Richard advised me to use R1/ 40 ohms and R2/ 600 ohms for DL 103. I am sure that these values should be good for DL 103 but I have a Marantz 7C clone with MM phono stage, that I connected Emerald to phono inputs on Marantz 7C.
The results of adding Marantz 7C between Emerald and power Amp was obviously distorted sound, bass was too boomy/muddy. so, I had to open JP1 to reduce gain to 40dB. The sound was much better than closing JP1. Bass was very rich and full, mid range sound is OK but definitely need more on high frequency sounds.
SO, Please can anyone advise me?
1. Do I need to leave open JP1 and changes the values of R1 and R2?
2. Do I need to close JP1 and changes the values of R1 and R2?
3. Is there any way to increase treble sounds?
First, I like to say thank you to Richard for providing me such a good phono stage. I have tried to build MC phono stage several times but never succeeded. However, at this time I can say that this project was successfully completed- "NO HUM" at all so far.
I received the boards from Richard in the beginning of May, and ordered all necessary parts. I did not use all day for this project but worked two hours pretty much everyday for two weeks and finally put them all together.
Richard advised me to use R1/ 40 ohms and R2/ 600 ohms for DL 103. I am sure that these values should be good for DL 103 but I have a Marantz 7C clone with MM phono stage, that I connected Emerald to phono inputs on Marantz 7C.
The results of adding Marantz 7C between Emerald and power Amp was obviously distorted sound, bass was too boomy/muddy. so, I had to open JP1 to reduce gain to 40dB. The sound was much better than closing JP1. Bass was very rich and full, mid range sound is OK but definitely need more on high frequency sounds.
SO, Please can anyone advise me?
1. Do I need to leave open JP1 and changes the values of R1 and R2?
2. Do I need to close JP1 and changes the values of R1 and R2?
3. Is there any way to increase treble sounds?
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hunsoop, excuse me intrude.
But allow me some points.
You say that you've connected Emerald to a phono input from Marantz c7 ?.
It will distort because you have increased the signal with Emerald and apart you have equalized it by increasing the bass and diminished the treble. This again happens in the phono stage of the Marantz c7.
The other thing I suggest is that you put insulation at least in high voltage welding, it is dangerous.
Finally, I see at least one channel of the Emerald that you have connected the ground of the cable in signal out and in earth of the plate you have connected signal of exit of the cable.
Sorry if I interfered.
regards
But allow me some points.
You say that you've connected Emerald to a phono input from Marantz c7 ?.
It will distort because you have increased the signal with Emerald and apart you have equalized it by increasing the bass and diminished the treble. This again happens in the phono stage of the Marantz c7.
The other thing I suggest is that you put insulation at least in high voltage welding, it is dangerous.
Finally, I see at least one channel of the Emerald that you have connected the ground of the cable in signal out and in earth of the plate you have connected signal of exit of the cable.
Sorry if I interfered.
regards
@hunsoop
Reviewing our previous email correspondence, I see that originally you asked about the Phonoclone, then on my suggestion you ordered the Emerald boards. My apologies, when you asked about the DL103 I was still thinking about the Phonoclone and gave you the answer for that circuit rather than the Emerald.
1. When using the DL103 with the Emerald, please use the usual BOM values of R1 47.5k and R2 100R.
2. When using the Emerald with the Marantz preamp, connect the phono stage to the line input, not the phono input. The phono input is for the accepting the phono cartridge output directly.
3. The main problem I see with your build is the jumpers of JP1 are both open. This is the MM position. For the DL103, both jumpers must be closed. Add the shorting jumper (mouser 517-952-10) across both sets of pins.
Those three points must be addressed to get your Emerald working properly.
Reviewing our previous email correspondence, I see that originally you asked about the Phonoclone, then on my suggestion you ordered the Emerald boards. My apologies, when you asked about the DL103 I was still thinking about the Phonoclone and gave you the answer for that circuit rather than the Emerald.
1. When using the DL103 with the Emerald, please use the usual BOM values of R1 47.5k and R2 100R.
2. When using the Emerald with the Marantz preamp, connect the phono stage to the line input, not the phono input. The phono input is for the accepting the phono cartridge output directly.
3. The main problem I see with your build is the jumpers of JP1 are both open. This is the MM position. For the DL103, both jumpers must be closed. Add the shorting jumper (mouser 517-952-10) across both sets of pins.
Those three points must be addressed to get your Emerald working properly.
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thank you Richard.
"Those three points must be addressed to get your Emerald working properly."
yes I did it_
i followed all your directions 1-3 and i am very impressed the sounds, treble was very detailed and bass was enough to enjoy. this is my first time to use MC cartridge DL 103 and I am very happy with the outcome.
my next plan is to upgrade 2.2uf capacitor - currently i have K75-10 2,.2uf 500v and the review was not bad and price was very reasonable on Ebay.
Do I need to spend more money on coupling Capacitor? please let me know your thoughts.
"Those three points must be addressed to get your Emerald working properly."
yes I did it_
i followed all your directions 1-3 and i am very impressed the sounds, treble was very detailed and bass was enough to enjoy. this is my first time to use MC cartridge DL 103 and I am very happy with the outcome.
my next plan is to upgrade 2.2uf capacitor - currently i have K75-10 2,.2uf 500v and the review was not bad and price was very reasonable on Ebay.
Do I need to spend more money on coupling Capacitor? please let me know your thoughts.
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Hi Richard,
I have an issue with my Phonoclone and need some advice. The story. My Rega Apheta fell apart (that's another story) and was replaced with an Apheta 2. The issue is it sounds dull and I have lost detail and imaging.
I suspect the issue is a loading mismatch between the cart and input effecting the freq response. Unfortunately Rega do not release much info on their carts, only resistance and voltage which is the same as the Apheta 1.
Any ideas??
I have an issue with my Phonoclone and need some advice. The story. My Rega Apheta fell apart (that's another story) and was replaced with an Apheta 2. The issue is it sounds dull and I have lost detail and imaging.
I suspect the issue is a loading mismatch between the cart and input effecting the freq response. Unfortunately Rega do not release much info on their carts, only resistance and voltage which is the same as the Apheta 1.
Any ideas??
The phonoclone has no loading to mismatch, so it's definitely not that. While of course all phono stages interact with cartridges, so it could be that the Apheta 2 does not "like" zero ohm load, I rather suspect something more mundane: either the new cartridge hasn't broken in yet or the stylus isn't as perfectly aligned / set up as your previous one.
Thanks for the reply,
The Rega Apheta and Rega tonearms have a 3 point mount that sets cartridge alignment and has no adjustment (maybe 50um sideways). Even so I still checked it with the protractor.
I cobbled up a JFET MC pre this morning and connected it to my old MM phono stage powered from a couple 9V batteries to verify whether it was the TT or preamp.
Conclusion the Apheta 2 does not like the Phonoclone. I have read reports that the Apheta 2 is very sensitive to loading, even though the raw specs are the same as the Apheta 1 the motor is completely different.
Oh well the search starts for a new phono preamp.
The Rega Apheta and Rega tonearms have a 3 point mount that sets cartridge alignment and has no adjustment (maybe 50um sideways). Even so I still checked it with the protractor.
I cobbled up a JFET MC pre this morning and connected it to my old MM phono stage powered from a couple 9V batteries to verify whether it was the TT or preamp.
Conclusion the Apheta 2 does not like the Phonoclone. I have read reports that the Apheta 2 is very sensitive to loading, even though the raw specs are the same as the Apheta 1 the motor is completely different.
Oh well the search starts for a new phono preamp.
Not all cartridges do, though this is the first definitive example I've come across. Speficially, carts with low resistance and high inductance may have a different frequency response into 0 ohms than the recommended load.
The only oddity in the specs of the Alpheta 2 that might be relevant is the recommended loading capacitance is a high 1000 pF.
The only oddity in the specs of the Alpheta 2 that might be relevant is the recommended loading capacitance is a high 1000 pF.