sachu888
Well-Known Member
Multilayer Ceramic or normal Ceramic caps are best for this application.Their size is also very small.
Regards,
Sachin
DIY Moving Coil phonostage
- Thread starter sachu888
- Start date
Multilayer Ceramic or normal Ceramic caps are best for this application.Their size is also very small.
Regards,
Sachin
No terrible hurry. Will get the caps and put in every part first. I'm also missing 10uF 35V electrolytes. I think these are missing from your parts list.
BTW, what is the role of the cute 100mH inductances?
That gets out HF noise. Output is LCL filter for pure DC.
sachu888
Well-Known Member
Hi Joshua,
they are Panasonic 10mh inductors,.There was a good amount of voltage drop with 100mh,so we replaced them with 10mh.
Regards,
Sachin
they are Panasonic 10mh inductors,.There was a good amount of voltage drop with 100mh,so we replaced them with 10mh.
Regards,
Sachin
Interesting site for buying electronic components: Surplus Sales of Nebraska
I wired my MC Phono preamp and fired it up with a DL-103. The preamp is pretty quite and no hum or noise. I am using 2 X 9V batteries.
My impressions on the sound are: the preamp is a pretty good effort and has a decent sound. Compared to my main phono stage in Yamaha C-60 preamp, the HTMCPS does not have the same dynamics. Overall it seem to be laid back and muted and not very detailed. It could be because of the opamp or the cartridge loading. The gain seems to be tad less compared to the Yamaha.
The system is EMT 938+ DL-103 connected to Pass F5 and Fostex BLH through the Yamaha preamp.
I need to tweak and change few things including Opamps, to see if I like the sound signature.
Cheers.
My impressions on the sound are: the preamp is a pretty good effort and has a decent sound. Compared to my main phono stage in Yamaha C-60 preamp, the HTMCPS does not have the same dynamics. Overall it seem to be laid back and muted and not very detailed. It could be because of the opamp or the cartridge loading. The gain seems to be tad less compared to the Yamaha.
The system is EMT 938+ DL-103 connected to Pass F5 and Fostex BLH through the Yamaha preamp.
I need to tweak and change few things including Opamps, to see if I like the sound signature.
Cheers.
Anil, look at cartridge loading resistances at input. Infact they are gain matching resistances as this is current in voltage out amplifier. Yes the OPAMPs make difference. Start with ad823, which I like the most. 49990 is best of all.
sachu888
Well-Known Member
Hi Anil,
All burr brown Opamps sound laid back.I have tried OPA2132/2134/2107 all were very laid back with good bass.If your system is neutral it may sound too plain.Try LM4562 which I sent you.AD823 was little forward and HF sounded shrill smoetimes.LMe49990 sounds best in my system,but they are SOIC and you will need 4(2 per channel) with this type of adapter 2 Dual SOIC to DIP 8 Convert PCB Adapter SMD OPA627 | eBay
I am not sure about low gain as people were complaining for too much gain Here It Is: The All Singing All Dancing HTMCPS - Page 18 - AudioKarma.org Home Audio Stereo Discussion Forums
Infect you can try lower resister value for DL-103.If you feel that gain is low try putting lower value resisters in place of 390 ohms.
Regards,
Sachin
All burr brown Opamps sound laid back.I have tried OPA2132/2134/2107 all were very laid back with good bass.If your system is neutral it may sound too plain.Try LM4562 which I sent you.AD823 was little forward and HF sounded shrill smoetimes.LMe49990 sounds best in my system,but they are SOIC and you will need 4(2 per channel) with this type of adapter 2 Dual SOIC to DIP 8 Convert PCB Adapter SMD OPA627 | eBay
I am not sure about low gain as people were complaining for too much gain Here It Is: The All Singing All Dancing HTMCPS - Page 18 - AudioKarma.org Home Audio Stereo Discussion Forums
Infect you can try lower resister value for DL-103.If you feel that gain is low try putting lower value resisters in place of 390 ohms.
Regards,
Sachin
sachu888
Well-Known Member
Please check your mail.I have just sent you Power supply manual.Post pics here before power it up.Be careful handling 230V mains current.Ask questions if in doubt.
Regards,
Sachin
kuruvilajacob
Well-Known Member
Dear Sachin,
I am happy to inform you that the MC phono stage for my DL 103 which i received last week has been soldered and put in a nice cabinet as directed in your mail. The initial result is very encouraging. It should improve as I use it for some more time. Perhaps 30 hrs ?. I am getting clean sound with good imaging and separation. I am looking forward to get better results as the burn in period gets over . Very good work Sachin. keep it up
I am happy to inform you that the MC phono stage for my DL 103 which i received last week has been soldered and put in a nice cabinet as directed in your mail. The initial result is very encouraging. It should improve as I use it for some more time. Perhaps 30 hrs ?. I am getting clean sound with good imaging and separation. I am looking forward to get better results as the burn in period gets over . Very good work Sachin. keep it up
Some opamp rolling questions:
1) any one has an idea what is the ideal supply voltage for opamp LM833? I tried running my Hypnotoad MC phono pre with +9V/0/-9V dual battery supply and it just creates some sort of croaking sound. I am suspecting that my supply voltage may be incorrect. Datasheet for LM 833 says "Dual Supply Operation: +/-5V to +/-18V".
2) I also tried TL072 and got nil output. Any idea if the DIP TL072 is dual opamp? And after checking the spec sheet, I realised that it couldn't have made any noise as the expected Vcc are +/- 18V! And I am driving it with +/-9V.
Need to try OPA 2132 too. I also bought NE5532 for the heck of it as they were darned cheap (Rs 10 a piece). I would love to lay my hands on AD823 and OPA 2107.
BTW, I have been using the LME49990 which Sachin sent me. This replaces the stock OPA2134 on the Hypnotoad MC phono preamp.
I find that the biggest change that the LM49990 brings about (compared to the OPA 2134) is a much more strident treble. So far this new sound hasn't really settled in my ears and I still like the OPA2134 more. I will allow more burn in time to form a better opinion. This could also mean that - for all I know - my VTA is less than ideal, and therefore treble sounds harsh when a more revealing component is introduced in the chain.
1) any one has an idea what is the ideal supply voltage for opamp LM833? I tried running my Hypnotoad MC phono pre with +9V/0/-9V dual battery supply and it just creates some sort of croaking sound. I am suspecting that my supply voltage may be incorrect. Datasheet for LM 833 says "Dual Supply Operation: +/-5V to +/-18V".
2) I also tried TL072 and got nil output. Any idea if the DIP TL072 is dual opamp? And after checking the spec sheet, I realised that it couldn't have made any noise as the expected Vcc are +/- 18V! And I am driving it with +/-9V.
Need to try OPA 2132 too. I also bought NE5532 for the heck of it as they were darned cheap (Rs 10 a piece). I would love to lay my hands on AD823 and OPA 2107.
BTW, I have been using the LME49990 which Sachin sent me. This replaces the stock OPA2134 on the Hypnotoad MC phono preamp.
I find that the biggest change that the LM49990 brings about (compared to the OPA 2134) is a much more strident treble. So far this new sound hasn't really settled in my ears and I still like the OPA2134 more. I will allow more burn in time to form a better opinion. This could also mean that - for all I know - my VTA is less than ideal, and therefore treble sounds harsh when a more revealing component is introduced in the chain.
sachu888
Well-Known Member
Hi Joshua,
+/-12V is ideal supply voltage for LM833.Are you using rechargeable batteries?I once tried those batteries in my CNC and it did sound like this.
OPA2132 and 2134 both are same you will hardly feel any difference. OPA2107 is better than both,laid back but more detailed than 2134.I can send you few Opamps for testing purpose.You can send m back after testing.I have LM4562, OPA2107, OPA2132, AD823 etc.
BTW I have also tried LM49720HA(Metal can).You can see the pic here http://www.audiokarma.org/forums/showthread.php?t=371889&page=101
Regards,
Sachin
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sachu888
Well-Known Member
Hi Anil,
Omishra is building Pearl 2.It costs very high,boards alone are $200+expensive PP caps.Pearl Gerber files are available so PCBs can be made.We can atleast save $100 if 10 r more members join.
I am not sure about NJFET RIAA.I once asked Salas for Gerber files for DCB1.He said he could not provide Gerber files as boards are already on sale on DIY audio store.
There is also an improved design for HTMCPS,but will only work for Low output MC carts.It uses 4X Opamps and sounds even better than well respected JFEts Phono stages DIY High End Moving Coil Phono Stage - AudioKarma.org Home Audio Stereo Discussion Forums
Regards,
Sachin
I am game for Pearl 2 GB. Let's check the interest level. Have a look at Salas RIAA amp. There are board designs in that thread at DIYAUDIO. Supposed to be quite good.
Fundamentally the noise floor is much lower for jFET based designs compared to opamps. I somehow always liked discrete designs compared to opamp based ones. There is a very big difference in quality between these from my personal experience. Coming from Pass Labs or Salas will be definitely superior.
I am also game for Pearl 2.
And also game for the new, improved Hypnotoad MC pre too, whenever the kit is made available. Apparently it is optimised for the AD797 opamp used in the input stage, for its low noise and low impedance. The output stage can be an opamp roller's delight. Again
@Sachin: are you and Hypno planning board only or will you bless us again with a complete kit buy of the new HTMCPS?
And also game for the new, improved Hypnotoad MC pre too, whenever the kit is made available. Apparently it is optimised for the AD797 opamp used in the input stage, for its low noise and low impedance. The output stage can be an opamp roller's delight. Again
@Sachin: are you and Hypno planning board only or will you bless us again with a complete kit buy of the new HTMCPS?
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sachu888
Well-Known Member
I am also game for Pearl 2.
And also game for the new, improved Hypnotoad MC pre too, whenever the kit is made available. Apparently it is optimised for the AD797 opamp used in the input stage, for its low noise and low impedance. The output stage can be an opamp roller's delight. Again
@Sachin: are you and Hypno planning board only or will you bless us again with a complete kit buy of the new HTMCPS?
Hi Joshua,
The first run of PCBs for new HTMCPS have already completed.I could not even keep one PCB for myself due to high demand in AK.Initial impression are very good,everyone has liked it.There is a good demand for PCBs in AK so another run is definitely on.Unfortunately that thread is moved to Barter town section of AK and only AK subscriber can see that.So you don't see any update there.
Newer Opamps are better and quieter.JFETs are always good.Pearl Phono is a Pass design it must be very good,I have no doubt.In a lighter note CNC MM Phonostage beats JFETs based Boozhound Laboratory Phonostage in every dept.That doesn't mean BHL product is not good but Lenco members now prefer CNC over BHL.Please read a very good review of williamsunique http://www.lencoheaven.net/forum/index.php?topic=9021.15
He is very experienced diyer and built various equipment and phonostages.He is so impressed that he changed his profile pic to CNC.
Regards,
Sachin
Yes, I'm using rechargeable 9V batteries. A downside to using 9V batteries is the rather low life. They don't last me 34-36 hours on a charge anymore.
I could not complete my OPS build for want of cabinet. Hopefully this will be resolved once Bibin starts shipping out his B1 cabs.
BTW, where do you buy genuine opamps from? I got only 4 different types here in Lamington Road.
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