Hi guys,
I could'nt follow this topic for over one (or more) year. In the beginning; the word "audiophile" sounded me too attractive and in fact I decided to make a clone of this, but by the time I lost my focus because of "unknown" reasons.
Anyway,
Now I am getting warm to this project again. 😀
But I have some question that strongly possible to asked and answered many times in this topic, but if you take consider its about 120 pages topic (woav) then have a quick answer from an experienced person is a better way to me
Please may somebody (an experienced one pls 🙂 answer these;
- A lot of versions available for this project (As I counted 4).... Which is the most stable and most audiophile one? For example; in the above photo there is a 22k/47K local positive feedback line for the LM3886. But the older versions have 10K/10K at the same position.... Should I use that one or older ones.
- May LM3875 instead of LM3886 usable in this project? Because I have a lot of LM3875 in my drawer 😀
- LM318 is the BEST for this position? Or a better one is tested?
- Do I need a buffer for this? May be its a stupid question.. But the complete circuit looks like me very complex and I cannot understand the working principle..
- Do I also need a DC servo for this?
- A PCB or kit is available for this project? So an instant solution....
Thats all...
Thx in advance..
I could'nt follow this topic for over one (or more) year. In the beginning; the word "audiophile" sounded me too attractive and in fact I decided to make a clone of this, but by the time I lost my focus because of "unknown" reasons.
Anyway,
Now I am getting warm to this project again. 😀
But I have some question that strongly possible to asked and answered many times in this topic, but if you take consider its about 120 pages topic (woav) then have a quick answer from an experienced person is a better way to me
Please may somebody (an experienced one pls 🙂 answer these;
- A lot of versions available for this project (As I counted 4).... Which is the most stable and most audiophile one? For example; in the above photo there is a 22k/47K local positive feedback line for the LM3886. But the older versions have 10K/10K at the same position.... Should I use that one or older ones.
- May LM3875 instead of LM3886 usable in this project? Because I have a lot of LM3875 in my drawer 😀
- LM318 is the BEST for this position? Or a better one is tested?
- Do I need a buffer for this? May be its a stupid question.. But the complete circuit looks like me very complex and I cannot understand the working principle..
- Do I also need a DC servo for this?
- A PCB or kit is available for this project? So an instant solution....
Thats all...
Thx in advance..
This takes you to MyRef Nirvana: http://twistedpearaudio.com/revc/revc.aspx
The MyRef RevC boards and parts are out of stock, but maybe they will be in again soon. I built several MyRef amps with those kits and I´m convinced they are worth every penny.
The MyRef RevC boards and parts are out of stock, but maybe they will be in again soon. I built several MyRef amps with those kits and I´m convinced they are worth every penny.
I have not built this amp, so I don't have hard facts, but some things appear clear to me (but don't nail me down on these):
With something other than the LM318 it's not the MyRev anymore and your one your own -- Mauro spent big effort on the compensation scheme, which is tricky and very specific for the LM318.
LM3875 looks suitable, at least considering the local compensation. Careful checking of the datasheets is still necessary.
I don't see the need for an input buffer, unlesse your source is extremely high impedance.
An english explanation of the circuit is given here:
http://www.twistedpearaudio.com/docs/project_my_ref.pdf
Or look at Mauro's site for more info (mostly italian, though)
http://www.webalice.it/mauro.penasa/Progetti_audio.html
- Klaus
With something other than the LM318 it's not the MyRev anymore and your one your own -- Mauro spent big effort on the compensation scheme, which is tricky and very specific for the LM318.
LM3875 looks suitable, at least considering the local compensation. Careful checking of the datasheets is still necessary.
I don't see the need for an input buffer, unlesse your source is extremely high impedance.
An english explanation of the circuit is given here:
http://www.twistedpearaudio.com/docs/project_my_ref.pdf
Or look at Mauro's site for more info (mostly italian, though)
http://www.webalice.it/mauro.penasa/Progetti_audio.html
- Klaus
SmellOfPoo said:
So I am missed the last bus again!
Do you think it sounds better than Pedja's JFET buffered gainclone?
Thx..
KSTR said:
Thanks Klaus... I'll examine the PDF then may be I will start that project.
Dxvideo said:
So I am missed the last bus again!
/B]
Well for a bit more of the long green you can always order Mauros more advanced My evolution kit which is still worth the money.
protos said:
I coulnt find on Twisted Pear... Just;
Twisted X Overture,
Twisted Power Module,
and MyRef RevC is listed... But MyRef is not available...
Requests for RevC
Hello Folks,
I have to say RevC seems to be enjoying a bit of a renaissance in terms of interest. Brian and I get email several times a week it seems showing interest.
I was quite a beginner with my first few revisions as you can see from that horrid schematic posted above. It actually humbling to look at it. It exposes how little I knew back then. 🙂 Not that I know much now.
I have a new PCB (for my own use) already in the works.
My new PCB will allow for both a faithful reproduction of Mauro's revisions A and C as well as something new. 😉
If there is enough interest I would not mind making more than enough for myself.
This circuit will not be the same as Mauro's "Evolution". I will not even attempt to reproduce that circuit as Mauro already has fine boards for that amp available. Anyone wanting that amp should get it from him. I will only distribute more PCBs if Mauro once again gives me explicit permission.
Many thanks to Mauro. It is largely this project he created that acted as a catalyst to my understanding (as elementary as it may be) of electronics.
To be honest I have so many other projects going on right now, I would not expect anything to happen too quickly. I will post if there are developments.
Cheers!
Russ
Hello Folks,
I have to say RevC seems to be enjoying a bit of a renaissance in terms of interest. Brian and I get email several times a week it seems showing interest.
I was quite a beginner with my first few revisions as you can see from that horrid schematic posted above. It actually humbling to look at it. It exposes how little I knew back then. 🙂 Not that I know much now.
I have a new PCB (for my own use) already in the works.
My new PCB will allow for both a faithful reproduction of Mauro's revisions A and C as well as something new. 😉
If there is enough interest I would not mind making more than enough for myself.
This circuit will not be the same as Mauro's "Evolution". I will not even attempt to reproduce that circuit as Mauro already has fine boards for that amp available. Anyone wanting that amp should get it from him. I will only distribute more PCBs if Mauro once again gives me explicit permission.
Many thanks to Mauro. It is largely this project he created that acted as a catalyst to my understanding (as elementary as it may be) of electronics.
To be honest I have so many other projects going on right now, I would not expect anything to happen too quickly. I will post if there are developments.
Cheers!
Russ
had a read about half the pgs but i still wonder if the LM318-LM3886 combo does indeed operate in class A output.
Also pcbs are not available at Russ'. Has anyone any other place?
cheers
Also pcbs are not available at Russ'. Has anyone any other place?
cheers
Re: Requests for RevC
Don't sell yourself short Russ. I noticed how quickly you've picked up this electronics lark with jealousy...
Stuey
Russ White said:
Don't sell yourself short Russ. I noticed how quickly you've picked up this electronics lark with jealousy...
Stuey
Oooh, I just ordered a kit from chipamp.com as the RevC's were 'not available'. I'd been waiting to get a job where I had some spending money, lol, now that I have it I can't get the revC kit, so that'd be awesome. I'll get one!
--
Nathan
--
Nathan
Hi All,
Having never owned a chip amp, I had to try this circuit and as most have reported, it is a very musical amp. I have been using it in the bedroom system for a couple weeks now, but haven't tried it with my Thors in the main system yet [Aleph 5]. With my Pinnacle bookshelves it has a very balanced uncolored sound, much better than expected.
Many thanks to Russ White for the artwork on the Twisted Pear website, which made it very easy.
If anyone is considering a chip amp I definately recommend that you try Mauro's design, it is outstanding.
Best to all, Bill
Having never owned a chip amp, I had to try this circuit and as most have reported, it is a very musical amp. I have been using it in the bedroom system for a couple weeks now, but haven't tried it with my Thors in the main system yet [Aleph 5]. With my Pinnacle bookshelves it has a very balanced uncolored sound, much better than expected.
Many thanks to Russ White for the artwork on the Twisted Pear website, which made it very easy.
If anyone is considering a chip amp I definately recommend that you try Mauro's design, it is outstanding.
Best to all, Bill
updated TP PCBs...
Uh, c'mon, Russ, tell us more... what's new?
will it have reg. PSU for the 318? class-A output mod for it? different input op-amp? (maybe one of the "SuSy" ones?) different power chip? balanced current-pump drive, perhaps with full "SuSy" structure? 😎
what else?
Russ White said:
Uh, c'mon, Russ, tell us more... what's new?
will it have reg. PSU for the 318? class-A output mod for it? different input op-amp? (maybe one of the "SuSy" ones?) different power chip? balanced current-pump drive, perhaps with full "SuSy" structure? 😎
what else?
Hi all,
I was thinking to make an "audiophile" gainclone for a long time. (As you can see under a lot of topics 🙂 )
Anyway, after a couple of project idea (like Pedja Rogic's JFET buffered LM3875 amplifier and some native GC attempts) I decided to make this project.
However, I already have a regulated power supply which is suitable for any gainclone. And I want to use that psu with this project (with some modifications on the project)
So, this is the "audiophile"gainclone modified by me;
And the power supply (with start up delay) I will use with that;
The output voltage will be +/-33v and the transformer is 225VA 2 x 30v toroidal.
Do you think it will sound as good as the original version? Or I will face a problem?
Thx..
I was thinking to make an "audiophile" gainclone for a long time. (As you can see under a lot of topics 🙂 )
Anyway, after a couple of project idea (like Pedja Rogic's JFET buffered LM3875 amplifier and some native GC attempts) I decided to make this project.
However, I already have a regulated power supply which is suitable for any gainclone. And I want to use that psu with this project (with some modifications on the project)
So, this is the "audiophile"gainclone modified by me;
An externally hosted image should be here but it was not working when we last tested it.
And the power supply (with start up delay) I will use with that;
An externally hosted image should be here but it was not working when we last tested it.
The output voltage will be +/-33v and the transformer is 225VA 2 x 30v toroidal.
Do you think it will sound as good as the original version? Or I will face a problem?
Thx..
I'm not the most qualified person to answer (Mauro would be the one... 🙂 ), but I don't see any reason why a regulated PSU shouldn't work. 🙄 Generally speaking, the only reasonable concerns w/r to a regulated PSU that come to my mind are:
1) regulator(s) bandwidth:
do they have low impedance and good enough regulation up to the full bandwidth of the amplifier? (i.e. at least up to ~50-100KHz?)
(mmmh, an interesting idea could be to design and build a wide-bandwidth PSU regulator using... another 3886! 😎 ).
2) noise:
regulators may introduce higher freq. noise which may be much worse than the simple PS ripple (at LF the 3886 have a quite high PSRR, but that falls down very quickly with increasing frequency...).
If these issues are properly worked out, that may be quite an interesting mod... I would be quite curious to see (hear...) which effects it may have on the sound.
BTW: in his new Evolution, also Mauro have adopted something better than the simple Zener that was used for the 318 in the original my_ref.