Dear reader,
I think it's time for you to put your own OREAD-EQ into practice.
Perhaps the original discussion and finding thread has become a bit too long and confusing, so I'm starting a brand new container for all our own builds of this interesting and certainly much underrated MM phono equalizer.
To get you in the mood, here is a PDF document containing all the image files backwards, i.e. up to just before the beginning.
I wish all DIY enthusiasts a lot of fun with OREAD, a daring concept. You will find all the necessary information in the thread itself, the components used are available worldwide and with @catd's circuit boards you can easily and absolutely safely rebuild OREAD.
Other board versions are also very welcome.
All the best to you,
hbt.audio
I think it's time for you to put your own OREAD-EQ into practice.
Perhaps the original discussion and finding thread has become a bit too long and confusing, so I'm starting a brand new container for all our own builds of this interesting and certainly much underrated MM phono equalizer.
To get you in the mood, here is a PDF document containing all the image files backwards, i.e. up to just before the beginning.
I wish all DIY enthusiasts a lot of fun with OREAD, a daring concept. You will find all the necessary information in the thread itself, the components used are available worldwide and with @catd's circuit boards you can easily and absolutely safely rebuild OREAD.
Other board versions are also very welcome.
All the best to you,
hbt.audio
The initial concern of the protagonists (@Chestnutspread and myself) was to show how easy it can be to go your own way - to set up a functional mm-equalizer without being dependent on a dictate or a doctrine. Everything should reflect the joy of one's own idea and realization and at the same time inspire reflection.
I hope that a not immodest number of oreads will see the light of day in 2025.
I hope that a not immodest number of oreads will see the light of day in 2025.
Hello Ed,
I completely agree with you. The so-called +1 error was deliberately not corrected or particularly addressed because I didn't want to unsettle the thread creator chestnutspread at the time and wanted to make the concept structured, simple and absolutely safe to rebuild. However, I touched on it in the form of mention the fourth time constant and claimed that we can neglect it as long as the edge falls constantly to >200kHz - and it does.
EXakt Mk2 corrects everything completely. But that's another story.
greetings,
HBt.
I completely agree with you. The so-called +1 error was deliberately not corrected or particularly addressed because I didn't want to unsettle the thread creator chestnutspread at the time and wanted to make the concept structured, simple and absolutely safe to rebuild. However, I touched on it in the form of mention the fourth time constant and claimed that we can neglect it as long as the edge falls constantly to >200kHz - and it does.
EXakt Mk2 corrects everything completely. But that's another story.
greetings,
HBt.
It should also be noted that developers such as Mr. Nick S. believe that there is still significant audio information above 20kHz on the vinyl pressing of a long-playing record and therefore the dubious Neumann constant must be included ..!
None of this is the case in reality, but what's the point?
The point is :
with the term +1 error I wanted to stimulate thought, essentially it expresses that a non-inverting amplifier cannot attenuate the input signal, but only boost it. This means that the required theoretical transfer function is (as usual) not 100% achievable.
The potential self-builder should not be confused. With a gain of +40dB at f=1kHz, everything is fine in any case.
None of this is the case in reality, but what's the point?
The point is :
with the term +1 error I wanted to stimulate thought, essentially it expresses that a non-inverting amplifier cannot attenuate the input signal, but only boost it. This means that the required theoretical transfer function is (as usual) not 100% achievable.
The potential self-builder should not be confused. With a gain of +40dB at f=1kHz, everything is fine in any case.
My casual observation is that my pre-amp with no systematic EQ error seems quieter than my pre-amp with the +1 error, but the two were several decades and phono cartridges apart.
Ed
Ed
Let's not digress here in the construction thread, but note that T3R = 75µsec is a wonderful (special) thing 😉. I'd love for this thread to be about crafting - and for us to see many new incarnations of the Oread theme.
Good night,
HBt.
Fire free
Good night,
HBt.
Fire free
on the current PCB circuit it is present.
https://www.diyaudio.com/community/attachments/oread_04_circ-jpg.1293012/
http://suzuki-gt250.de/misc.electronics/AUDIO/OREAD/
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I am building a new preamp specifically for the AT-VM95ML cartridge.
I am going to see how good this cart can be.
I am going to see how good this cart can be.
What peculiarities of this cartridge do you want to address and how?
I only know of the relatively low connection capacitance values that are given for the AT systems, otherwise no special features.
I would recommend the NPN version of the OREAD for this, as mentioned here: https://www.diyaudio.com/community/threads/oread-a-diy-mm-phono-approach.406480/post-7759014
I only know of the relatively low connection capacitance values that are given for the AT systems, otherwise no special features.
I would recommend the NPN version of the OREAD for this, as mentioned here: https://www.diyaudio.com/community/threads/oread-a-diy-mm-phono-approach.406480/post-7759014
Audio Technica
Hello ...
@stocktrader200
I use the simplest VM95C (blue) and it works perfectly with my OREAD version.
I hope you enjoy it,
HBt.
Hello ...
@stocktrader200
I use the simplest VM95C (blue) and it works perfectly with my OREAD version.
Would you like to realize our EQ, that would be a great honor for catd and me, great.
I hope you enjoy it,
HBt.
...
The MM system itself is an absolute standard and well known, the decisive difference here will be the needles with their cut. Of course, no MM can mutate into an MC, which means that there is no electronic trick to get more out of a tactile pickup than its physics dictates. No Neumann constant, no electrical cooling, or any other phrase can do this, not even a polshift through an atomatic offset correction.
If you have your own idea of an ingenious implementation of the equalization and preamplification process, I look forward to seeing it soon.
#
The MM system itself is an absolute standard and well known, the decisive difference here will be the needles with their cut. Of course, no MM can mutate into an MC, which means that there is no electronic trick to get more out of a tactile pickup than its physics dictates. No Neumann constant, no electrical cooling, or any other phrase can do this, not even a polshift through an atomatic offset correction.
If you have your own idea of an ingenious implementation of the equalization and preamplification process, I look forward to seeing it soon.
#
Therefore, in my case, the line capacity of my cables (and connectors) is already sufficient and there is no additional Cx on the oread print necessary. The same for the newest supra24.
A little advertising on our own behalf is allowed, a two-stage (very simple) active equalizer design:
Eiskalt MC-EQ
With standard components (without agony of selection and pairing) two-stage, for MC's. The 75µs de-emphasis is implemented here as it should be in principle. The "ice-cold approach" rounds off the EQ issue for me, because according to some experts it should simply be completely useless - but it is not
😉.
... back to the many buildings of our nice little OREAD EQ.
kindly,
HBt.
Eiskalt MC-EQ
With standard components (without agony of selection and pairing) two-stage, for MC's. The 75µs de-emphasis is implemented here as it should be in principle. The "ice-cold approach" rounds off the EQ issue for me, because according to some experts it should simply be completely useless - but it is not
😉.
... back to the many buildings of our nice little OREAD EQ.
kindly,
HBt.
Hello "stocktrader200"
Can you already report on your phono EQ investigation in conjunction with the audio technica VM95 (ML) ?
Fantastic! I finally signed up here, and I really appreciate being welcomed.
To be honest, I don’t even know exactly what I’m doing here 😂. I’m completely inexperienced in this field, but I’ve read all the discussions about this phono preamp, and I actually enjoyed confusing myself trying to understand concepts that, in reality, are beyond my grasp—both theoretically and practically. Well, maybe practically a little less… after all, I do know how to use a soldering iron and a few basic tools.
The truth is that, in a nostalgic moment of my 60s, I’ve thrown myself headfirst back into analog, and from there, my obsession with phono preamps has only grown. It all started when I bought a Project Phono Box for just under 100 euros, and as I always do, I opened the case to see what was inside. The result? I felt completely ripped off! The outer casing is nice, compact, and solid, and that’s basically the only thing I paid for because the internal components are embarrassing—even for a beginner like me.
But does a good MM phono preamp exist that isn’t just a commercial gimmick with a few cheap components thrown together on a tiny board? Do you have any recommendations for an easy-to-build yet truly high-quality kit, available on eBay or elsewhere? The market is huge, and I wouldn’t want to end up with something disappointing.
I would absolutely love to build a phono preamp like the Oread—I’ve read everything about it, and the only thing I fully understood is that it sounds amazing! Too bad it’s beyond my skill level… and, well, my nickname says it all 😂.
The real issue is that once you realize that what they sell you is worth only a tenth of the price you pay, it becomes really hard to justify buying these “tin boxes.” If this phono preamp were sold as a kit, how much would it actually cost?
To be honest, I don’t even know exactly what I’m doing here 😂. I’m completely inexperienced in this field, but I’ve read all the discussions about this phono preamp, and I actually enjoyed confusing myself trying to understand concepts that, in reality, are beyond my grasp—both theoretically and practically. Well, maybe practically a little less… after all, I do know how to use a soldering iron and a few basic tools.
The truth is that, in a nostalgic moment of my 60s, I’ve thrown myself headfirst back into analog, and from there, my obsession with phono preamps has only grown. It all started when I bought a Project Phono Box for just under 100 euros, and as I always do, I opened the case to see what was inside. The result? I felt completely ripped off! The outer casing is nice, compact, and solid, and that’s basically the only thing I paid for because the internal components are embarrassing—even for a beginner like me.
But does a good MM phono preamp exist that isn’t just a commercial gimmick with a few cheap components thrown together on a tiny board? Do you have any recommendations for an easy-to-build yet truly high-quality kit, available on eBay or elsewhere? The market is huge, and I wouldn’t want to end up with something disappointing.
I would absolutely love to build a phono preamp like the Oread—I’ve read everything about it, and the only thing I fully understood is that it sounds amazing! Too bad it’s beyond my skill level… and, well, my nickname says it all 😂.
The real issue is that once you realize that what they sell you is worth only a tenth of the price you pay, it becomes really hard to justify buying these “tin boxes.” If this phono preamp were sold as a kit, how much would it actually cost?
OREAD is not a commercial product.
To put together a kit, someone would have to buy the parts privately and then resell and ship them. That would be more expensive than if you got the parts yourself.
You can get the empty OREAD boards from me. Send me a PM if you want some.
There is a BOM (bill of materials) for the required components. You can see this and some notes here:
http://suzuki-gt250.de/misc.electronics/AUDIO/OREAD/
To put together a kit, someone would have to buy the parts privately and then resell and ship them. That would be more expensive than if you got the parts yourself.
You can get the empty OREAD boards from me. Send me a PM if you want some.
There is a BOM (bill of materials) for the required components. You can see this and some notes here:
http://suzuki-gt250.de/misc.electronics/AUDIO/OREAD/
Grazie mille, ma devo restare fedele al mio soprannome... 😉 Sarebbe troppo impegnativo e mi bloccherei al primo ostaco, visto che non sono molto esperto. Ecco perché un kit già pronto su eBay sarebbe l'ideale per me. Ma visto che non ne so niente, quale?
Google translate added by Moderator:
Thank you very much, but I have to stick to my nickname... 😉 It would be too much work and I would get stuck at the first obstacle, since I'm not very experienced. That's why a ready-made kit on eBay would be ideal for me. But since I don't know anything about it, which one?
Google translate added by Moderator:
Thank you very much, but I have to stick to my nickname... 😉 It would be too much work and I would get stuck at the first obstacle, since I'm not very experienced. That's why a ready-made kit on eBay would be ideal for me. But since I don't know anything about it, which one?
Last edited by a moderator:
Dear member, this is an English speaking forum. Always add a translation please.
Translate:
Gentile membro, questo è un forum in lingua inglese. Si prega di aggiungere sempre una traduzione.
Translate:
Gentile membro, questo è un forum in lingua inglese. Si prega di aggiungere sempre una traduzione.