Hi Bob,
they're not combined, they're alternative setup!
DCB1+LightSpeed
OR
Stepped attenuator alone
What I'm sayng is that the attenuator sounds better than DCB1+LS, IMHO
Now I can't compare anymore since both the LS and the smd attenuator are broken... (static discharge for the LS and too much soldering/desoldering for the attenuator...)
Attachments
I can confirm that a stepped attenuator with Vishay/Dale discrete resistors sounds very transparent with the MyRef. It's not my setup, but a local audiophile's (which I believe is a Valab stepped attenuator, not DACT).
Buffering the LED/LDR attenuator whilst not buffering the stepped attenuator is not comparing like for like.
There are 4 arrangements to compare.
1.) Stepped attenuator alone, determine the attenuator impedance/resistance that gives best sound at your normal listening volume.
2.) LED/LDR attenuator alone. Again determine the control currents into the LEDs for best sound quality at your normal listening volume.
3.) buffered stepped attenuator.
4.) buffered LED/LDR attenuator.
Comparing only 2 of these options and not optimising any of them to suit the MyRef input impedance and required source impedance, proves nothing other than a waste of time and typing.
There are 4 arrangements to compare.
1.) Stepped attenuator alone, determine the attenuator impedance/resistance that gives best sound at your normal listening volume.
2.) LED/LDR attenuator alone. Again determine the control currents into the LEDs for best sound quality at your normal listening volume.
3.) buffered stepped attenuator.
4.) buffered LED/LDR attenuator.
Comparing only 2 of these options and not optimising any of them to suit the MyRef input impedance and required source impedance, proves nothing other than a waste of time and typing.
OK. So how should I proceed then?
First it was claimed that I didn't need a buffer, using the 10K pot Penasa recommended, as the LM318 was acting as a buffer.
Then it was said that's not the case, and I do need buffer.
Then I thought, maybe the LDR attenuator could be used directly, as the LDR attenuator seen by the MyRefC would be just one fixed resistance.
How do you suggest I should determine the LDR control currents for that setup? Using the constant current source version?
First it was claimed that I didn't need a buffer, using the 10K pot Penasa recommended, as the LM318 was acting as a buffer.
Then it was said that's not the case, and I do need buffer.
Then I thought, maybe the LDR attenuator could be used directly, as the LDR attenuator seen by the MyRefC would be just one fixed resistance.
How do you suggest I should determine the LDR control currents for that setup? Using the constant current source version?
I am building a stereo active two way MyRef amplifier to be used in conjunction with DCX-2496. I am using INA134 to receive differential input and PGA2310 for volume control. (My amps are built using linuxguru's v1.4 PCB).
Had to go for 2310 because I need to change volume on 4 different amplifiers simultaneously, as the volume control is going to be in between cross-over and MyAmp. Any comments on this setup? Why everyone using LDR or descrete resistor based volume control instead of volume control chips such as PGA2310? I think PGA2310 is also using a resistor network internally.
Thanks!
Had to go for 2310 because I need to change volume on 4 different amplifiers simultaneously, as the volume control is going to be in between cross-over and MyAmp. Any comments on this setup? Why everyone using LDR or descrete resistor based volume control instead of volume control chips such as PGA2310? I think PGA2310 is also using a resistor network internally.
Thanks!
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It's certainly worth trying - perhaps there's a belief that the PGA2310 may not be as linear or transparent-sounding as a stepped attenuator or LED/LDR attenuator, because of the switches and other active elements inside the PGA2310. Please post your audible impressions after you build it.
No, it depends on output impedance of your CD player.
In my case it works well but yours could be different.
If you had read my previous posts you'll know that I was going to compare the same attenuator buffered and not buffered...
Andrew, is always a pleasure reading yours kind and relevant posts... 😉
Sure, I will post my overall impression (not just comparing volume control modules) compared to a couple of HT receivers..
Hey Siva,
Are you going to keep us in suspense?😉
Can you tell us what your preferred volume control is - without stepping on anyones toes?
Bob
Are you going to keep us in suspense?😉
Can you tell us what your preferred volume control is - without stepping on anyones toes?
Bob
Always glad to see fresh discussion of these amps, but maybe it's time for a new thread: Input strategies for the MyRef.
After a heavy work out with loud rock, one of my older amps started buzzing pretty badly, so I finally hooked up one of my "new" Ultimate BOM MyRef's, and the results are marvelous: slightly more detail and transparency without a hint of brightness, and a more spacious soundstage. I used a nude Vishay at R12 instead of a Shinkoh tant. Still got a Shinkoh at R10; all the rest are PRP's. Caps are what came with the ultimate BOM, except for the Sonicap at C13 and silver mica's in a couple places. Wow.
My new speakers are finally operating, but they need some fine tuning and finishing. MyRef runs the mids/tweets with a passive xover, while Class D runs the bass bins. ESP active xovers between bass and mids/tweets. I made a preliminary post in Multi Way, but there didn't seem to be any interest in my build. Maybe I'll start another thread there. I'll be selling my B&W 802's because they are completely outclassed.
Peace,
Tom E
After a heavy work out with loud rock, one of my older amps started buzzing pretty badly, so I finally hooked up one of my "new" Ultimate BOM MyRef's, and the results are marvelous: slightly more detail and transparency without a hint of brightness, and a more spacious soundstage. I used a nude Vishay at R12 instead of a Shinkoh tant. Still got a Shinkoh at R10; all the rest are PRP's. Caps are what came with the ultimate BOM, except for the Sonicap at C13 and silver mica's in a couple places. Wow.
My new speakers are finally operating, but they need some fine tuning and finishing. MyRef runs the mids/tweets with a passive xover, while Class D runs the bass bins. ESP active xovers between bass and mids/tweets. I made a preliminary post in Multi Way, but there didn't seem to be any interest in my build. Maybe I'll start another thread there. I'll be selling my B&W 802's because they are completely outclassed.
Peace,
Tom E
Personally I have no doubts that only a passive remote controlling can compare to an LDR, TVC or stepped pot. When the signal goes through ANY volume control chip or input switching chip, it will go through passive and active parts that will hurt the sound quality.
It's little use putting top quality passive parts outside if you then go through such chips.
Hopefully not too off topic.
Hi Tom,
Great to hear of the progress on your new speaker design.I remember you mentioning them months ago. I would be interested in your approach - meaning what specific elements of the units like the B&Ws were you trying to improve upon? I am familiar with the honeycomb internal bracing they use for rigidity and it looks like you took a diferent approach. Can you relay what is significant in the size/shape of the molded baffle? (Probably on the other thread)
I am also working on a bi-amp setup, but I'm using the MyRefs and the LM3886x3 board from Jim's Audio on eBay. I have a DBX 2/3/4 way unit and hope I won't have to go to a DIY to make good music.
Linuxguru commented a while back that one might get a more concise/unified result from a single MyRef compared to a bi-amped setup. It will be interesting to see the outcomes. I know others have tried this and it would be good to hear from them.
I like the idea of a new thread for "MyRef input experiences". I hope it gets started.
Regards, Bob M
Hi Tom,
Great to hear of the progress on your new speaker design.I remember you mentioning them months ago. I would be interested in your approach - meaning what specific elements of the units like the B&Ws were you trying to improve upon? I am familiar with the honeycomb internal bracing they use for rigidity and it looks like you took a diferent approach. Can you relay what is significant in the size/shape of the molded baffle? (Probably on the other thread)
I am also working on a bi-amp setup, but I'm using the MyRefs and the LM3886x3 board from Jim's Audio on eBay. I have a DBX 2/3/4 way unit and hope I won't have to go to a DIY to make good music.
Linuxguru commented a while back that one might get a more concise/unified result from a single MyRef compared to a bi-amped setup. It will be interesting to see the outcomes. I know others have tried this and it would be good to hear from them.
I like the idea of a new thread for "MyRef input experiences". I hope it gets started.
Regards, Bob M
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Not wishing to sound sarcastic or critical, and probably doing so, I'd say that if we don't imagine ways to improve the MyRef from the outside, there's no much that can be done about it.
That's one of the reasons I lost interest on the original MyRef thread, where Mauro Penasa was an active participant. But you couldn't change anything or the whole thing would not work.
You couldn't use other chip than the LM318; you couldn't bridge or parallel it; you couldn't improve on the zener regulation for the 318 with something better; it was claimed that using a high current regulator for the whole thing was a waste of money. And so and so.
What was the fun of that? Where was the DIY curiosity then?
If through experimenting with input interfaces we can get things moving, let them come!
That's one of the reasons I lost interest on the original MyRef thread, where Mauro Penasa was an active participant. But you couldn't change anything or the whole thing would not work.
You couldn't use other chip than the LM318; you couldn't bridge or parallel it; you couldn't improve on the zener regulation for the 318 with something better; it was claimed that using a high current regulator for the whole thing was a waste of money. And so and so.
What was the fun of that? Where was the DIY curiosity then?
If through experimenting with input interfaces we can get things moving, let them come!
Hi Bob - my preferred volume control is no volume control 🙂.
But on a more serious note, the best I've heard is a stepped attenuator driven directly from the CD player; I haven't heard an LED/LDR based attenuator, buffered or unbuffered, as yet.
My own setup uses a lowly carbon-track pot, and is adequate but nowhere as transparent as a good stepped attenuator. I'll upgrade to a stepped attenuator eventually.
bi-amping myrefC
I put 4 myrefC boards into a bi-amping mono-block configuration, and the results were very good, though The speakers (elsinores), are intended to be bi-amped (passive crossovers).
I built them for my brother and i figured they would be easy to convert to a stereo pair if the bi-amping monos proved unnecesary. In my brothers paticular set up, bi-amping did bring a solid improvement. I was concerned about the input impedance drop bi-amping would bring, but it did not SOUND like a big deal.
I optioned for uriah's LDR deal during the group buy last year, and well, bye,bye attenuators( I spent a lot of time messing around with attenuators, and resistors before I got the LDR) . Right now I am incorporating the Lighternote into a DAC build for my brother, to tie into the myrefC's. I will spend some time playing around with the impedance of the lightspeed to find the sweet spot. I am curious as to where it will end up being.
Who else has tried the bia-amping configuration? How did it turn out? Was it worthwhile?
I also like the idea of a myrefC input thread.
Ben
I put 4 myrefC boards into a bi-amping mono-block configuration, and the results were very good, though The speakers (elsinores), are intended to be bi-amped (passive crossovers).
I built them for my brother and i figured they would be easy to convert to a stereo pair if the bi-amping monos proved unnecesary. In my brothers paticular set up, bi-amping did bring a solid improvement. I was concerned about the input impedance drop bi-amping would bring, but it did not SOUND like a big deal.
I optioned for uriah's LDR deal during the group buy last year, and well, bye,bye attenuators( I spent a lot of time messing around with attenuators, and resistors before I got the LDR) . Right now I am incorporating the Lighternote into a DAC build for my brother, to tie into the myrefC's. I will spend some time playing around with the impedance of the lightspeed to find the sweet spot. I am curious as to where it will end up being.
Who else has tried the bia-amping configuration? How did it turn out? Was it worthwhile?
I also like the idea of a myrefC input thread.
Ben
Hi Folks,
It sounds like there is solid interest in an “input” discussion. Let me suggest that we try to determine if that is part of the “Build Process” or a topic that deserves its own thread. All comments and opinions are welcomed and encouraged.
My interest is based on my desire to use uncompressed FLAC and Apple Lossless media as the core to work from. IMHO they are the formats of the future. I have heard nothing better and it’s hard for me to believe a giant tube amp and a multi-thousand dollar CD player would offer significant improvement. Ones and zeros from a USB stick are identical to ones and zeros stuck on the bottom of a CD platter.
What I have tried so far:
1. USB memory stick -> computer -> Denon HT -> Lexicon DAC -> MyRef.
2. Apple iPod -> Lighter Note -> MyRef. (for Apple Lossless)
3. Sansa Clip -> Lighter Note -> MyRef. (for PC based files)
4. MP3 decoder (see link 1. below) as source. Surprisingly good performance but as yet unable to decode uncompressed media.
I also purchased a DIY DAC (see link 2. below) to be part of a super straight forward signal path consisting of Memory stick (USB or high speed SD card) -> DAC -> LN -> MyRef. I don’t think one can get more “straight through” unadulterated than that.
So just in my experiments, there are multiple paths and topics to have fun with. I really want to explore all the possibilities to enhance the MyRef experience at the same time understanding the need to keep a sense of clarity and simplicity in a forum topic.
What say you?
1. MP3 hardware decoder+Remote control unite | eBay
2. WM8740 x2 DIR9001 PCM2706 RCA/USB input DAC kit ! | eBay
It sounds like there is solid interest in an “input” discussion. Let me suggest that we try to determine if that is part of the “Build Process” or a topic that deserves its own thread. All comments and opinions are welcomed and encouraged.
My interest is based on my desire to use uncompressed FLAC and Apple Lossless media as the core to work from. IMHO they are the formats of the future. I have heard nothing better and it’s hard for me to believe a giant tube amp and a multi-thousand dollar CD player would offer significant improvement. Ones and zeros from a USB stick are identical to ones and zeros stuck on the bottom of a CD platter.
What I have tried so far:
1. USB memory stick -> computer -> Denon HT -> Lexicon DAC -> MyRef.
2. Apple iPod -> Lighter Note -> MyRef. (for Apple Lossless)
3. Sansa Clip -> Lighter Note -> MyRef. (for PC based files)
4. MP3 decoder (see link 1. below) as source. Surprisingly good performance but as yet unable to decode uncompressed media.
I also purchased a DIY DAC (see link 2. below) to be part of a super straight forward signal path consisting of Memory stick (USB or high speed SD card) -> DAC -> LN -> MyRef. I don’t think one can get more “straight through” unadulterated than that.
So just in my experiments, there are multiple paths and topics to have fun with. I really want to explore all the possibilities to enhance the MyRef experience at the same time understanding the need to keep a sense of clarity and simplicity in a forum topic.
What say you?
1. MP3 hardware decoder+Remote control unite | eBay
2. WM8740 x2 DIR9001 PCM2706 RCA/USB input DAC kit ! | eBay
Totally agreed. Since the beginning, this design was looked at as being something magical, people even got angry when changes were proposed.
On the other hand, people are not afraid of screwing up Nelson Pass designs by trying to improve them, for example.
Totally un-understandable.
It's not exactly so...
LM318 could be changed but you must know how to prevent oscillation when the compensation network is gone.
Improving PS is easier and it gives good results (I've had great reports from Suburra using batteries instead of Zeners).
Even Penasa himself changed LM318 PS using zeners + transistors on MyRef Evolution.
On the MyRef Evolution also C9 was replaced by a DC servo...
I think there is space for DIY, isn't it? 😉
I'm good at component selection but I'm not able in circuit design... someone want to design a simple TL431 regulator for LM318?
The only one that got angry at proposed changes was Penasa, which is understandable as the MyRef was his son. But people didn't have to agree so willingly.
As long as you don't go into oscillation or something, changing distortion in any way (which I think is what most of the times happens when changes are perceived), you should be allowed to change things.
Nelson Pass is one of the few that seems to take changes to his designs with an open mind, and even helping if something goes wry. I believe the DIYForum is a think-tank, and should be considered as a place where people want to try different things, certainly not to ruin something someone else did.
Do you know of anyone who tried a different chip with its own compensation network instead of the 318 and was happy with it?
About the LM318 regulation, I mean putting something a little bit better than a zener, which is very poor as audio-applied regulator. Even a 7XXX, which I think is poor too, might be an improvement. Did someone try it?
Where can I get some info about this DC servo used on the Evolution version?
Here there are two versions of simple regulators with TL431, which would probably be better than the zeners in MyRefC.
TL431 Shunt Regulator Calculator
3K9 and 820 ohms for the resistors will get you 14.4v.
Using the version with LM317 will probably sound better, but should difficult to fit on the MyRef existing board.
As long as you don't go into oscillation or something, changing distortion in any way (which I think is what most of the times happens when changes are perceived), you should be allowed to change things.
Nelson Pass is one of the few that seems to take changes to his designs with an open mind, and even helping if something goes wry. I believe the DIYForum is a think-tank, and should be considered as a place where people want to try different things, certainly not to ruin something someone else did.
Do you know of anyone who tried a different chip with its own compensation network instead of the 318 and was happy with it?
About the LM318 regulation, I mean putting something a little bit better than a zener, which is very poor as audio-applied regulator. Even a 7XXX, which I think is poor too, might be an improvement. Did someone try it?
Where can I get some info about this DC servo used on the Evolution version?
Here there are two versions of simple regulators with TL431, which would probably be better than the zeners in MyRefC.
TL431 Shunt Regulator Calculator
3K9 and 820 ohms for the resistors will get you 14.4v.
Using the version with LM317 will probably sound better, but should difficult to fit on the MyRef existing board.
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