Hello,
I'm looking for your help, what would be a good MC preamp in my case.
For decades I'm using my heavily modified Rega TT (with acryl platter, DDS based motor control ...) with MM pickup.
Now I've acquired a Systemdek IIX 900 and looking to buy a Goldring Eroica (or similar) into it. Low output MC (do not have good experience with high output MC).
The problem is, I do not have a transformer and with the pickup I will spend my budget for a year, can not buy a 1000 EUR transformer now.
In the 90s, I've used to have MC preamp. I had an Ortofon MC10 with preamp first, than with T5. The T5 was different, but not necessarily better to me, on the other hand, more simple to use. I've planned to get a better transformer, but never had.
Now, in the last decades I've used DAC as main source, but LP in parallel also. Lately, LP is used more and that is why I bought the Systemdek.
I'm not sure yet about the Eroica, so I'm not sure about the transformer either and that is the point when I've decided, I build a decent solid state preamp.
The chain after that is a tube riaa and preamp, similar to Audio Note M7 on circuit, than a 2A3 PSE amp.
On LP I'm listening mostly classical and jazz.
Do you have a suggestion for me for a good MC preamp circuit?
What do you think, what is the best diy MC preamp? (I mean, of course it depends on the building more, but anyway, with similar component and build quality, which is the best you would recommend?)
Thanks!
JG
I'm looking for your help, what would be a good MC preamp in my case.
For decades I'm using my heavily modified Rega TT (with acryl platter, DDS based motor control ...) with MM pickup.
Now I've acquired a Systemdek IIX 900 and looking to buy a Goldring Eroica (or similar) into it. Low output MC (do not have good experience with high output MC).
The problem is, I do not have a transformer and with the pickup I will spend my budget for a year, can not buy a 1000 EUR transformer now.
In the 90s, I've used to have MC preamp. I had an Ortofon MC10 with preamp first, than with T5. The T5 was different, but not necessarily better to me, on the other hand, more simple to use. I've planned to get a better transformer, but never had.
Now, in the last decades I've used DAC as main source, but LP in parallel also. Lately, LP is used more and that is why I bought the Systemdek.
I'm not sure yet about the Eroica, so I'm not sure about the transformer either and that is the point when I've decided, I build a decent solid state preamp.
The chain after that is a tube riaa and preamp, similar to Audio Note M7 on circuit, than a 2A3 PSE amp.
On LP I'm listening mostly classical and jazz.
Do you have a suggestion for me for a good MC preamp circuit?
What do you think, what is the best diy MC preamp? (I mean, of course it depends on the building more, but anyway, with similar component and build quality, which is the best you would recommend?)
Thanks!
JG
Have a look at the "Pearl-3"
Yes.... I know, that this is a complete riaa for both MM & MC, but first... It´s not that expensive to build, and available in the store as a complete kit,
and second...... It is really worth while.
You won´t regret it 😉
Yes.... I know, that this is a complete riaa for both MM & MC, but first... It´s not that expensive to build, and available in the store as a complete kit,
and second...... It is really worth while.
You won´t regret it 😉
I experimented with various MC preamplifiers, transistor, jFET and even tube circuits. The problem is the inherent noise and the good power supply (battery charged when not in use).
At the end I settled at a pair of Lundahl LL1678 transformers shielded with permalloy sheet. No noise an pretty much free of hum.
At the end I settled at a pair of Lundahl LL1678 transformers shielded with permalloy sheet. No noise an pretty much free of hum.
I’m less worried about a bit of hum. When I had MC preamp, it less bothered me. PSU was an issue, did tried with bunch of NiCd batteries, but it was a pain in… Nowdays I would just use a parkside pack is single rail is enough. If not, than I just build a pack from 18650s. I think what I’ve used required a single 24V, but worked fine from 15 also.
I’m more concerned it will harsh or soft or just wash away details.
Thanks,
JG
I’m more concerned it will harsh or soft or just wash away details.
Thanks,
JG
TL072 with 12V transformer adaptor. At very light load, I split it to about +/- 8.5 V, it was enough.
It works well enough on a Thorens turntable linked to a simple Philips amp, Sony speakers.
May be too basic for your tastes.
Or else just copy the MC / phono stage of 1980s Japanese amplifiers, some had extra boards off the main amp for this purpose.
5532 or equivalent chips from Mitsubishi.
At the most OPA2134, and sometimes these boards are available already assembled, and sometimes as ready PCB, so you can put your choice of gold plated marijuana fiber capacitors, or whatever strikes your fancy.
I stick to local Keltron caps (Sprague licence).
There are many reputed names for capacitors, just buy whatever is easily availale in your area, and if you feel like use 1% tolerance resistors.
It works well enough on a Thorens turntable linked to a simple Philips amp, Sony speakers.
May be too basic for your tastes.
Or else just copy the MC / phono stage of 1980s Japanese amplifiers, some had extra boards off the main amp for this purpose.
5532 or equivalent chips from Mitsubishi.
At the most OPA2134, and sometimes these boards are available already assembled, and sometimes as ready PCB, so you can put your choice of gold plated marijuana fiber capacitors, or whatever strikes your fancy.
I stick to local Keltron caps (Sprague licence).
There are many reputed names for capacitors, just buy whatever is easily availale in your area, and if you feel like use 1% tolerance resistors.
Can't go wrong with a W.M. Leach common-base unit. These, and numerous derivatives, both DIY and commercial, have been used since the early 80, and work quite well. Being battery powered, all the AC/DC conversion issues are avoided.
Moving Coil Cartridge Head Amps
Built my first one @'88. Built a newer one in 2019. Simple, effective, cheap and work great.
Moving Coil Cartridge Head Amps
Built my first one @'88. Built a newer one in 2019. Simple, effective, cheap and work great.
Hi seanc,
In theory, yes. However it really comes down to execution. You've got to keep an open mind.
You also would like to avoid a coupling capacitor for the input, so JFets make that task easier. Many super units use paralleled JFets on the input.
In theory, yes. However it really comes down to execution. You've got to keep an open mind.
You also would like to avoid a coupling capacitor for the input, so JFets make that task easier. Many super units use paralleled JFets on the input.
Well of course, but in general it's preferred, and held so by many highly regarded designers/designs.
For an op amp solution, AD797 or LT1115 are better choices for LOMC than JFET inputs.
The Leach does so nicely, as do many others.
1. Head amps:
here you got article about it >> MC head amp made by member Bonsai.
2. SUT:
if you got MM riaa phono you may buy it. Unfortunately there will be probably problem with proper cartridge loading in case of SUT ratio. You may buy ie Lundahl or Sowter with 2 or 3 different ratios that will help deal with it for a reasonable price.
3. Phono stage without SUT:
if you want to design something new look at project Platina. Very, very good sounding, and relatively cheap.
It will be up to you what and how much impedance and capacitance matching and gain you will use.
here you got article about it >> MC head amp made by member Bonsai.
2. SUT:
if you got MM riaa phono you may buy it. Unfortunately there will be probably problem with proper cartridge loading in case of SUT ratio. You may buy ie Lundahl or Sowter with 2 or 3 different ratios that will help deal with it for a reasonable price.
3. Phono stage without SUT:
if you want to design something new look at project Platina. Very, very good sounding, and relatively cheap.
It will be up to you what and how much impedance and capacitance matching and gain you will use.
Hi, Thanks a lot for all!
I think I try the AD797 input stage also (however, I did not prefer opamps in audio chain, but ... who knows), as well as I'm hunting what transistor or transistor array I can build a Hiraga MC.
I will not build a complete MC to riaa for sure, the AN M7 like circuit I use is performing excellent for me.
Transformers? Yes. I'm hunting some good used transformer, but I can not found yet. What makes it worst, I've ordered a Hana SL, not an Eroica, which is harder to match 🙂 More challenges. So now, I want to build a good MC preamp first.
Lundahl transformer: yes, I like them very much. I love my DAC with an Lundahl interstage after the I/ resistor and before the triode stage. But, as I see a good one (a pair) will cost more than for example an AN S2 what I'm hunting.
M. Leach, very interesting article! On the other hand, that output by two caps is a bit strange to me. I do not know. BUT, guess what was my very first amplifier what I've built? M. Leach Low TIM amplifier. I've loved it and used all the was to when I've built the 2A3 PSE. In the meantime I've built several transistor power amps, but none was able to replace my Leach Low TIM amp. So, ... I guess I have to build one. 2N4401 and 2N4403 I see at Mouser, not in any webshop in Hungary.
Thanks for all your input !!!!
If you still have a suggestion, I aim the best MC preamp I can build. Best would be, if the transistors (or arrays even better) can be sourced easier. I know that 2SC1775A is available on ebay for example, but I have doubts if those are really 2SC1775As.
-by the way, I have some THAT300 in a headphone amp I'm not using-
I think I try the AD797 input stage also (however, I did not prefer opamps in audio chain, but ... who knows), as well as I'm hunting what transistor or transistor array I can build a Hiraga MC.
I will not build a complete MC to riaa for sure, the AN M7 like circuit I use is performing excellent for me.
Transformers? Yes. I'm hunting some good used transformer, but I can not found yet. What makes it worst, I've ordered a Hana SL, not an Eroica, which is harder to match 🙂 More challenges. So now, I want to build a good MC preamp first.
Lundahl transformer: yes, I like them very much. I love my DAC with an Lundahl interstage after the I/ resistor and before the triode stage. But, as I see a good one (a pair) will cost more than for example an AN S2 what I'm hunting.
M. Leach, very interesting article! On the other hand, that output by two caps is a bit strange to me. I do not know. BUT, guess what was my very first amplifier what I've built? M. Leach Low TIM amplifier. I've loved it and used all the was to when I've built the 2A3 PSE. In the meantime I've built several transistor power amps, but none was able to replace my Leach Low TIM amp. So, ... I guess I have to build one. 2N4401 and 2N4403 I see at Mouser, not in any webshop in Hungary.
Thanks for all your input !!!!
If you still have a suggestion, I aim the best MC preamp I can build. Best would be, if the transistors (or arrays even better) can be sourced easier. I know that 2SC1775A is available on ebay for example, but I have doubts if those are really 2SC1775As.
-by the way, I have some THAT300 in a headphone amp I'm not using-
@Giordano
I skipped the amp and built Leach's preamp with his stepped attenuator. it needs some cap maintenance now but it's been my only preamp ever since.
when my turntable was up and running I was using the original Leach pre-preamp
too. good stuff.
Leach's upgrades to these preamps look interesting but I'm leaning towards replacements designed by Wayne Colburn at the moment.
the 4401-03 pair are good units.
I skipped the amp and built Leach's preamp with his stepped attenuator. it needs some cap maintenance now but it's been my only preamp ever since.
when my turntable was up and running I was using the original Leach pre-preamp
too. good stuff.
Leach's upgrades to these preamps look interesting but I'm leaning towards replacements designed by Wayne Colburn at the moment.
the 4401-03 pair are good units.
Hi Giordano,
I wouldn't expect any obsolete transistor to be available in quantity anywhere. It can happen, but I would be extremely careful about it.
You don't like op amps? Too bad, everything you listen to has already been through more op amps than you can count. Today's op amps are a far cry from the LM741 or TL072. Even the NE5534 performs better than most other technologies you can build. That goes for subjective opinions. What is probably suspect is the layout of the board or configuration.
I wouldn't expect any obsolete transistor to be available in quantity anywhere. It can happen, but I would be extremely careful about it.
You don't like op amps? Too bad, everything you listen to has already been through more op amps than you can count. Today's op amps are a far cry from the LM741 or TL072. Even the NE5534 performs better than most other technologies you can build. That goes for subjective opinions. What is probably suspect is the layout of the board or configuration.
4401/3 are certainly still good low-noise, but can be bettered today.
THAT300 is NPN only, you need at least 1-NPN + 1-PNP. I used the THAT340, 2 x matched NPN + 2 x matched PNP in the same package. The matching allowed eliminating emitter degeneration for lowest noise. I built the updated "Current Mirror" version, went way overboard with chassis design & switching functions, but basic circuit doesn't need it.
re: op amps. The right ones are eminently suitable for LOMC amplification. I've built an AD797 unit that is excellent. Not stand-alone though, an expansion card to the Apt Holman preamp:
Apt Holman plug-in MC expansion board
The basic circuit is simple, and could be used stand-alone with an appropriate power supply.
I run both above at 32-33dB gain, even at that much, they are very qui
Nice implementation!
Them thar THATs remind me of the Motorola units Dick Marsh used in his passive phono preamp in 1980.
And these new units would be neat for his Pooge-3 line stage too.
Them thar THATs remind me of the Motorola units Dick Marsh used in his passive phono preamp in 1980.
And these new units would be neat for his Pooge-3 line stage too.