AudioCircle
Industry Circles => Empirical Audio => Topic started by: audioengr on 14 Mar 2013, 07:09 pm
-
Background:
I recently got the 75 ohm termination plug-in for my GHz scope. Very expensive BTW. This new tool allowed me to see what I could never see before: exactly what is happening at the S/PDIF termination and the jitter there. This revealed that my current circuit, which is typical for transformer-coupled galvanically isolated S/PDIF, was holding-back the performance of both the Synchro-Mesh and the Off-Ramp 5. Bummer :scratch: Not that the jitter was high, but it should be a LOT lower that what I am measuring.
Investigation:
In order to determine the cause of this, which is incidently very difficult to observe, I embarked on a multi-week prototyping of different pulse transformers and associated circuits with several Synchro-Meshes. I got help from the transformer designer too. Yesterday I had a breakthrough. I realized that I don't need to change to a custom transformer as I had anticipated. Some circuits changes and tuning will be sufficient.
Conclusions:
1) I discovered that the impedance of the S/PDIF source is critical to getting low jitter from S/PDIF coax. Even 1 ohm off makes a big difference. This is why most manufacturers cannot get it even close and why so many users believe that S/PDIF coax is a broken standard. Most other products that I modded in the past did not even have 75 ohm output impedance, much less exactly 75 ohms.
2) Pulse transformers can be inconsistent in characteristics. They are wound with tape etc, so the spacings vary from one to the next. These differences result in ratio and impedance differences.
3) I believe based on anecdotal evidence that break-in of the device changes the impedance, so tuning it when the device is not broken-in might require a re-tuning later to optimize for jitter.
I am in the final stages of testing of the mod now. I still need to verify the repeatability of the mod and the effect of break-in. I will be posting some before and after jitter plots soon.
The impact for me and my customers is an inconvenience for both, but I believe that this one will be worth it. I expect this mod to cost about $200.00 for either product. Other companies would put it in the next product, but I believe this is so important that I have to get it out ASAP. This is another reason to stick with Empirical Audio.
Exciting development. More to come.
Steve N.
-
Great news Steve! Looking forward to reading more.
can the mod be applied to OR4?
-
Aww Steve, I am still running in my OR5.
Is this the mod to which that you have eluded previously, or are there others?
Anthony
-
I would assume that this would not apply to those of use using OR5 with I2S....?
-
Steve, does this mod replace the need to connect some BNC-RCA adapter on the unused output port of SM?
/path
-
Hard to imagine that Steve's really good stuff keeps on getting even better :thumb:
-
Great news Steve! Looking forward to reading more.
can the mod be applied to OR4?
Yes, at least the later baseboard.
-
Aww Steve, I am still running in my OR5.
Is this the mod to which that you have eluded previously, or are there others?
Anthony
No, that was a tweak that users can do using a stub, which was a BNC to RCA or similar connector.
This mostly negates the need for tweaks, although the tweak may imrpove things for some cables.
Steve N.
-
I would assume that this would not apply to those of use using OR5 with I2S....?
Correct. This is only for S/PDIF coax outputs.
Steve N.
-
Steve, does this mod replace the need to connect some BNC-RCA adapter on the unused output port of SM?
/path
Yes.
-
Hi Steve,
How long will be needed to have the mod applied?
Regards,
Jean-Pierre
-
Hi Steve,
How long will be needed to have the mod applied?
Regards,
Jean-Pierre
I can do it in an hour. I should be able to fit mods in every 2-3 days. If I get 30 at once, its obviously going to delay things...
I have a customer with 2 SMs, so maybe he will be the first to compare an unmodded to a modded in his own system. I'll ask.
Steve N.
-
No, that was a tweak that users can do using a stub, which was a BNC to RCA or similar connector.
This mostly negates the need for tweaks, although the tweak may imrpove things for some cables.
Steve N.
Hi
Not sure what this means can you elaborate or point to a thread... Thanks much.
-
Hi
Not sure what this means can you elaborate or point to a thread... Thanks much.
See:
http://www.audiocircle.com/index.php?topic=106328.120 (http://www.audiocircle.com/index.php?topic=106328.120)
-
As promised, here are the before and after mods jitter plots of Synchro-Mesh (both use standard wall-wart):
Before Mods - the scale is 106psec/div, so most of the jitter is in the 150 psec range
(http://www.audiocircle.com/image.php?id=77091)
After Mods - the scale is 57 psec/div so most of the jitter is in the 60-70 psec range
(http://www.audiocircle.com/image.php?id=77092)
Here is the Sonos Jitter plot:
(http://www.audiocircle.com/image.php?id=77093)
As you can see, the worst case jitter is 10nsec.
Here is a zoom to one of the Sonos peaks
(http://www.audiocircle.com/image.php?id=77095)
the peaks each have around 150-170psec of jitter and then there are other smaller peaks as well, but less samples.
Steve N.
-
I'm not familiar with these graphs, but can we conclude that the mod version produces about half less jitter?
Simon
-
Oh dear, I have 2 SM on the way & this happens :lol:
-
I'm not familiar with these graphs, but can we conclude that the mod version produces about half less jitter?
Simon
That is correct 50% reduction at least.
Steve N.
-
Oh dear, I have 2 SM on the way & this happens :lol:
Sorry, just bad timing. I didn't know at the time. If you wanted to return one and pay shipping costs both ways, I'll do the mod to it for free if you can compare the modded and unmodded and report back here.
Thanks,
Steve N.
-
Very impressive work, Steve. For what it's worth, Stereophile measured about 70psec from the Simaudio Moon 650D, an $8K CD player/DAC, so that's good company to be in. Most of the average USB > S/Pdif converters are in the 300+ range.
-
Very impressive work, Steve. For what it's worth, Stereophile measured about 70psec from the Simaudio Moon 650D, an $8K CD player/DAC, so that's good company to be in. Most of the average USB > S/Pdif converters are in the 300+ range.
The SM is actually much better than that. The transformer and galvanic isolation is the impediment. I'm getting 20psec or less once I remove the transformer. I'm thinking about winding my own version now. :scratch:
I will post more plots soon.
Steve N.
-
Here is a plot using a new transformer (these may take time to procure):
(http://www.audiocircle.com/image.php?id=77145)
And just for grins, I did basically the same circuit, but no transformer:
(http://www.audiocircle.com/image.php?id=77146)
Even though the new transformer jitter is on the order of 40psec, I can hear the difference with no transformer at <20psec. It's particularly noticable in vocalists. More solid and 3-D.
Now, what to do????
I am thinking because the edge-rates are so fast with the no-transformer output that I need to sell a cable to go with that mod if I do it. Lesser cables will puke with it I think :o Even my own Bitmeister is not good enough. The user must also use the same AC outlet for the SM and DAC.
The good thing about the transformerless solution is that I can do it right away, no waiting for parts.
In the meantime, I'm enjoying it :thumb:
Steve N.
-
LOL! Well Steve, hang on to my SMR till you get all the bugs worked out. No hurry at all.
I am using an API Power Wedge Ultra 116 that features Balanced A/C, and some trick filtering. It has individual isolation transformers for each outlet. Would the no transformer solution for the SMR be a problem here? I power the entire system off this thing... It works very well btw... Even for the amps.
-
LOL! Well Steve, hang on to my SMR till you get all the bugs worked out. No hurry at all.
I am using an API Power Wedge Ultra 116 that features Balanced A/C, and some trick filtering. It has individual isolation transformers for each outlet. Would the no transformer solution for the SMR be a problem here? I power the entire system off this thing... It works very well btw... Even for the amps.
Well if the two things are not grounded together or they are on the same ground, it should be good. It's only a problem if the grounds are different.
Steve N.
-
Here is my current thinking:
Two upgrade options, OTL and OT (Output TransformerLess and Output Transformer):
OTL option:
If you have a DAC like the Overdrive SE with galvanically isolated S/PDIF coax input, remove the transformer from the SM or OR5 and make the other circuit changes. Only one transformer is needed for galvanic isolation. This also removes the RCA output jack on the SM, so includes a BNC-RCA adapter. Include a 4-foot BNC-BNC 75 ohm cable of high quality with the mod. This achieves less than half the jitter of the OT option.
OT option:
If you have a typical DAC, replace the transformer in the SM or OR5 and make the other circuit changes. This may require hand-tuning with the scope to optimize jitter performance.
Pricing for OT will be around $150.00 plus shipping.
Pricing for OTL depends on the cable cost. I expect it to be in the $200-$250 range for mod and cable. For those with the right DAC, this could save you hundreds on the cable.
Steve N.
-
Sweet! My Bel Canto has galvanic isolation on all the S/PDIF inputs... So, if you think going without the transformer is the best option, then make mine that way please.
-
Sweet! My Bel Canto has galvanic isolation on all the S/PDIF inputs... So, if you think going without the transformer is the best option, then make mine that way please.
Okay, will do.
Steve N.
-
Steve, ship me one of the modded units and I will measure it on Audio Precision 2722, then you can compare numbers with the old one John Atkinson measured in Stereophile. You can ship it with the cable of your choice (bnc will eliminate the need for adapter on AP2722).
-
Steve, a few questions below:
1) If my DAC only has RCA input, does this mean that I would not be able to use the OTL version?
2) Would the usage of a BNC-RCA adapter plug be an option on the DAC side right after your BNC-BNC cable or would it degrade sound more than just getting the OT version?
3) Would you offer a BNC-RCA version of your custom coax cable as well (for us non-BNC DAC owners)?
4) Do you remember if the Northstar m192 DAC you modded for me a few years ago already has isolated coax inputs, as required for the OTL version?
5) Just out of curiosity, when listening to your Overdrive (still on my wishlist) how does the sound compare (jitter-wise) between
a) coax input from a modded OTL OR5/SM
b) I2S connection from OR5
c) internal direct USB connection (is this still best since no external digital cable is needed?)
Best, /patrick
-
Steve, ship me one of the modded units and I will measure it on Audio Precision 2722, then you can compare numbers with the old one John Atkinson measured in Stereophile. You can ship it with the cable of your choice (bnc will eliminate the need for adapter on AP2722).
I have an OR5 that I can use for this. I need to modify it first, probably to the transformerless version (OTL).
Send me an email about this.
Steve N.
-
Steve, a few questions below:
1) If my DAC only has RCA input, does this mean that I would not be able to use the OTL version?
No, I may offer it with RCA also. I just need to find a suitable RCA plug or us a BNC to RCA adapter. I may make the cable optional.
2) Would the usage of a BNC-RCA adapter plug be an option on the DAC side right after your BNC-BNC cable or would it degrade sound more than just getting the OT version?
IT will probably degrade a bit.
3) Would you offer a BNC-RCA version of your custom coax cable as well (for us non-BNC DAC owners)?
Possible.
4) Do you remember if the Northstar m192 DAC you modded for me a few years ago already has isolated coax inputs, as required for the OTL version?
IT does not have transformers, so you need the OT version.
5) Just out of curiosity, when listening to your Overdrive (still on my wishlist) how does the sound compare (jitter-wise) between
a) coax input from a modded OTL OR5/SM
b) I2S connection from OR5
I think the OTL S/PDIF coax might be better.
c) internal direct USB connection (is this still best since no external digital cable is needed?)
The OR5 with OTL has overtaken everything because of the external Hynes supply.
Steve N.
-
Hey Steve,
I used to, in my CRT projection days..I used to transmit the HD video in analog. Hardwired inside the Projector, and hardwired into the video card.
video card modded, entire CRT projector modded, and so on.
I used mini RG-62 as cables.
I custom tweaked the impedance of each, by hand, using my eye, with variable caps and variable resistors.
I did this at each end of each cable, painstakingly, and slowly wound it down to the best pairing of end terminations for each cable. Took a month or more. Brutal work.
People thought I was nuts, but the system was so tweaked, that this effort, the effect of it...was readily visible. It made it get that much closer to perfection. I took quite the beatings for all those experiments and results, over at AVSforum.
It just goes to show that a thing can be very real, and it's reality can simply be in the observing and noting of it. That it does not need to be verified via measurement before it is allowed to exist.
That the ears are the most complex system of sensory input in the human body. More neural horsepower is dedicated to hearing than nay other sense. That the senses do not need to be of a visual nature in order for the given sense to verify. Hearing can be believing too, as it is a case of even more neural input than any other sense.
I trust my ears to about as much as I trust my capacity for rumination and deduction. That some of us self trust, hear better and ruminate a bit more objectively than others might. Even though it may be delegated as being entirely subjective due to no measurements being applied. Many of us are like this. And many are not. Thus the arguments are born.
It is good that you have measured it, and please whack a few linear-minded moles for me, they need it.
-
Hi Steve,
(1) I'm thinking to upgrade my digital RCA cable, possibly Cabledyne Silver or Nordost Heimdall 2 (I'm currently using Grover digital RCA cable with a RCA to BNC adapter on SM side). After I read this thread, I'm thinking OTL option for my SM. It seems to be more user-friendly to those who aren't tech savvy like myself. Will I still be able to use "other cables" mentioned above or it must be used with yours? My dac is Metrum Octave that only has RCA inputs.
By the way, I'm also on your waiting list for your modded version of Paul Hynes 12v power supply for my SM.
(2) One other separate question. Is there a specific reason you recommend digital cable to be 1.5m (not 1m or 2m)?
Best,
-
Hi Steve,
(1) I'm thinking to upgrade my digital RCA cable, possibly Cabledyne Silver or Nordost Heimdall 2 (I'm currently using Grover digital RCA cable with a RCA to BNC adapter on SM side). After I read this thread, I'm thinking OTL option for my SM. It seems to be more user-friendly to those who aren't tech savvy like myself. Will I still be able to use "other cables" mentioned above or it must be used with yours? My dac is Metrum Octave that only has RCA inputs.
You can certainly use any cable you want. I was just surprised that even my Bitmeister was outclassed by the silver coax 75 ohms with BNC's that I built. It is a 4-footer. That's why I want to make an inexpensive cable that delivers.
(2) One other separate question. Is there a specific reason you recommend digital cable to be 1.5m (not 1m or 2m)?
Yes, 1.5m is a good middle-ground that works with all interfaces. I think certainly with OTL you could go to a 1m length, but never 0.5m. The reflections come too soon and effect the jitter. Longer is okay, but starts to affect performance if too long.
Steve N.
Best,
[/quote]
-
Steve,
1) Are you now actually able to measure the performance degradation in terms of jitter which occurs when signal goes through a digital coax cable (e.g. using the SM output and comparing jitter with to without cable inserted)?
2) Do you think about offering your newly designed/assembled digital coax cable as a stand alone product as well? (the price / performance ratio seems rather astonishing)
/patH
-
Steve,
1) Are you now actually able to measure the performance degradation in terms of jitter which occurs when signal goes through a digital coax cable (e.g. using the SM output and comparing jitter with to without cable inserted)?
I have not specifically looked at this yet. All I know is the 75 ohm coax I made sounds better than my expensive Bitmeister for the first time ever.
2) Do you think about offering your newly designed/assembled digital coax cable as a stand alone product as well? (the price / performance ratio seems rather astonishing)
/patH
I am thinking about this. They are not too difficult to build, but I still have to buy an expensive crimper and make the optimum size crimps from scratch, probably brass tubing.
Steve N.
-
Steve,
Are your latest plots of jitter measurements on modded SM in OT and OTL version done with standard wall-wart power supply or with your modded Paul Hynes SR3-12 power supply?
(on the first measurement plots you indicated "standard wall-wart")
/patH
-
Steve,
Are your latest plots of jitter measurements on modded SM in OT and OTL version done with standard wall-wart power supply or with your modded Paul Hynes SR3-12 power supply?
(on the first measurement plots you indicated "standard wall-wart")
/patH
These are all with the wall-wart. The Hynes is in the system and I'm listening to it so I don't want to take it out :nono:
Steve N.
-
I have been getting some ORs and SM back for this mod already, so here is a result for an OR5 with OT mod:
(http://www.audiocircle.com/image.php?id=77545)
Here is a loaded OR4 before the OTL mod - not shabby :thumb::
(http://www.audiocircle.com/image.php?id=77546)
Here is the same loaded OR4 after the OTL mod - more than cuts it in half:
(http://www.audiocircle.com/image.php?id=77547)
All of these used the wall-wart that I am currently shipping with OR5 and SM.
BTW, I did a shootout between the SM with OTL and the OR4 with OTL above. The OR4 beats the SM. I used Jimi Hendrix "all along the watch tower" with both 96 and 44.1 SM with OTL. Its not detail that is different. There just seems to be more HF energy and jump factor with the OR4. I think this is one artifact of upsampling. If you like a slightly more mellow laid-back sound, but all of the detail and same imaging, the SM does this. Vocalists were virtually identical as well as soundstaging. Its the percussion where the OR wins. If you are using PM rather than my favorite version of Amarra, they would probably be identical.
Steve N.
-
Thanks Steve, I think that is my OR4! Just clarifying that the standard deviation of the jitter is the stat that matters, they all seem to have the same mean. I guess the mean is some function of the sample rate, and the scatter around that mean is related to the timing errors.
looking forward to hearing the modded OR4!
I was interested to read your comments that a modded OR5 with hynes power supply beats the inboard USB of overdrive. What are your thoughts for the future development of the overdrive? I can see it going two ways: a) try to implement the same power supply improvements to the inboard USB interface through upgraded substation or b) conclude that perhaps external USB interface has technical benefits and consider the option of a trimmed down overdrive which does not have an internal USB interface.
Thanks for doing the mod on my OR4 so quickly and posting the jitter analysis. Great to see you are really pushing the boundaries of what is possible in digital audio.
Cheers,
Andrew
-
Steve, one more question: Is the wall-wart that you are currently shipping with OR5 the same as the one you were using for OR4 in December 2011?
Cheers,
Andrew
-
Thanks Steve, I think that is my OR4! Just clarifying that the standard deviation of the jitter is the stat that matters, they all seem to have the same mean. I guess the mean is some function of the sample rate, and the scatter around that mean is related to the timing errors.
The Std Dev and the P-P is what matters. The thinness of the peaks also seems to matter. The thinner, the better.
I was interested to read your comments that a modded OR5 with hynes power supply beats the inboard USB of overdrive. What are your thoughts for the future development of the overdrive? I can see it going two ways: a) try to implement the same power supply improvements to the inboard USB interface through upgraded substation or b) conclude that perhaps external USB interface has technical benefits and consider the option of a trimmed down overdrive which does not have an internal USB interface.
There are some internal tweaks that I can do to the Overdrive yet, including more Hynes regs. I intend to give these a try to see what difference it makes. Also, the digital supply of the Overdrive could be driven from a linear with Hynes reg. This is even easier to try. That's probably what I'll try first.
Thanks for doing the mod on my OR4 so quickly and posting the jitter analysis. Great to see you are really pushing the boundaries of what is possible in digital audio.
Its exciting to know that there is a lot of performance left in there trying to get out.
Steve N.
-
Steve, one more question: Is the wall-wart that you are currently shipping with OR5 the same as the one you were using for OR4 in December 2011?
Cheers,
Andrew
No, its a new one. Smaller and faster responding.
Steve N.
-
I have received my OR4 with the OTL mod ( same one which Steve showed the jitter plots earlier in the thread). The OR4 has dual Turboclock and USB Hynes reg. Output is Via BNC plug to BNC input of Audio Research DAC8. Downstream of that is Conrad Johnson ACT2, CJ Prem140 and Dynaudio C1. All cabling is Kimber Select (1030,1036,3035), except Steves new BNC-BNC digital cable. Source is a modded 2011 Mac Mini with SSD, fanless, Wifi and Bluetooth antennae removed, external DC linear power supply, Mountain Lion and Audirvana+, Kimber Ag Bus USB cable.
Steve also sent me one of the smaller wallwarts to replace the one issued with the OR4.
When I installed the modded OR4 I could immediately hear a dramatic improvement. It is particularly noticeable on high quality recordings like Madeleine Peryoux Careless Love (44.1/16, on the fly upsampling to 88.2 in Audirvana).
I would describe the improvements as consistent with what the standard offramp does, but taking it to a new level. There is a significantly improved soundstage, and overall a more realistic, natural sound. The improved realism of piano notes is quite noticeable. Seems like the new OR is capturing the transient of the piano notes better.
I havent yet tried swapping back the old wallwart or my old digital cables (Kimber 2020 0.75m and CanbleDyne Silver 1.5m). I will report back when I try these swaps.
The next upgardes I have in mind are: Steves new Hynes power supply for the OR when it becaomes available, Better quality power supply for the mac mini (thinking about Teddy Pardo 12/4 supply), and a higer end USB cable like Audioquest Diamond.
For anyone with an existing OR, the new mods are strongly recommended. The improvements are not subtle. It feels like an improvement that should cost thousands, not hundreds of dollars.
-
New to this forum but I just got OR-5 back from Steve with OT Mod and his new BNC-BNC cable. Still settling in but it’s a huge improvement. Sound is 3D and wide open with lots of new delicate realistic detail. Less artificial, more real. Great!
Front end: JPlay 5.1. > Dual PC > EA Short Block > OR-5 with turbo clocks, S/PDIF Hynes regulator, OT Mod w/ EA BNC to BNC Cable > NAD M-51 DAC/Pre.
Highly recommended.
-John Lambert
-
Thought I would share my findings of the SMR with OTL Mod and the new digital cable Steve sent with it. Here is the quote I emailed him:
"Gulp.....WOW! It's back, and with a vengeance! Keener resolve, quieter, more jump, and much tighter focus. That about sums it up."
If you have an SMR and your DAC is galvanically isolated at the S/PDIF input, I would suggest that you get it to Steve to have the OTL mod done to it.
I also compared his cable to my Oyaide Silver BNC to BNC cable. While the Oyaide is very good, it is a little softer in presentation. It is very close, however....Steve's cable is better.
With Steve's cable, the images are more dense, with better focus, and the overall presentation has more jump and better detail discernability.
-
Any idea when the Off Ramp 6 will be released?
-
Any idea when the Off Ramp 6 will be released?
Probably late in the year, maybe 6 months. Lots of design work going on, including custom XMOS chip design.
Steve N.
-
Steve, are you still planning on sending me Offramp 5 for AP measuements?
-
Hi Steve,
Will there be a possibility to trade in my OR5 towards the purchase of an OR6?
Or should I go for the OT mod right away?
Best regards,
Jean-Pierre
-
Just some feedback, now that I got my SM back with the OT mod (my DAC does not allow for OTL) and new EA digital coax cable.
I must say I am absolutely blown away by the effect of the latest mods, which puts the SM in an entirely different class now. What surprizes me most is the extension in perceived bandwidth and absolute clarity and density at both ends of the spectrum, as if I had upgraded the amp and the speakers as well. And best of all, the rather polite sound of my modded Northstar DAC is now explosive and incredibly live sounding with a rock solid sound stage even when I move around in my room. WOW!
Such extremely low degree of jitter somehow reveals musically interesting, subtle and involving aspects in just about every recording I listened to, across all genres. Even very low volume listening is now possible, no need to turn it up to get fully immersed in musical enjoyment.
I took the time to compare EA's new digital coax to my silver reference Cabledyne cable (about same price) and the difference is substantial. There's no going back for me, Steve's got a winner there!
The least I could say is that my latest investment definitely does not follow the law of diminishing returns. Not at all.
/patrick
-
Steve, are you still planning on sending me Offramp 5 for AP measuements?
Yes, but I need to keep one for the Newport Beach show (can't risk it) as well as ship one to the EMC labs for radiation testing.
I'll have to build another one or two when the orders slow. Did you want the OTL version?
Steve N.
-
No preferences on my end. Whichever one measures and/or sounds better. You can send me both as it doesn't take a whole lot of time to measure them once setup is ready. My dac at home has input transformers on both aes/ebu and spdif inputs. I have squeezebox transporter at work I can connect it to and provide jitter plots on the analog out.
-
No preferences on my end. Whichever one measures and/or sounds better. You can send me both as it doesn't take a whole lot of time to measure them once setup is ready. My dac at home has input transformers on both aes/ebu and spdif inputs. I have squeezebox transporter at work I can connect it to and provide jitter plots on the analog out.
Perfect, then OTL it is. I really wanted to ship you a Hynes supply with it. I only have one and I don't know when I'll get the next one. :scratch:
Steve N.
-
Hi Steve,
Will the new OT mod come up on the SMR order page? Thanks!
Charles
-
Hi Steve,
Will the new OT mod come up on the SMR order page? Thanks!
Charles
Its standard now. The only option is OTL.
Steve N.
-
Hi Steve,
Is it worth sending you my OR5 right away for OT mod or better to wait for OR6? (How much better will it be?)
Do you plan to offer upgrade plans from OR5 to OR6 in the future?
Best regards,
Jean-Pierre
-
Hi Steve,
Is it worth sending you my OR5 right away for OT mod or better to wait for OR6? (How much better will it be?)
Do you plan to offer upgrade plans from OR5 to OR6 in the future?
Best regards,
Jean-Pierre
I think the mod is worth it. The OR5 will be upgradable to OR6, but it will not be cheap, probably $500 upgrade. It will be quite a few months before OR6 is available. No telling if it will sound better or not.
Steve N.
-
SM OTL mod is absolutely fantastic! Wholeheartedly agree with path73 and others. I did not order (or try) his new BNC cable from Steve however.
BTW, can't wait for the day Steve is able to ship out Paul Hynes 12v supply.
-
does anyone know the difference between Spartan6 FPGA and XMOS? Is DSD support the only difference, does one sound better than the other?
-
does anyone know the difference between Spartan6 FPGA and XMOS? Is DSD support the only difference, does one sound better than the other?
DSD is a function of the design, not the chip. Both of these are capable. in theory the same designer can make them sound identical. The jitter depends on the ancillary design stuff, the kind of stuff that I do for instance.
Steve N.
-
USB power?
Does the OR5 / OR6 need the power from the USB cable? Can I use a USB cable with no power leg it in?
-
USB power?
Does the OR5 / OR6 need the power from the USB cable? Can I use a USB cable with no power leg it in?
OR5 does not need +5
OR6 will need it.
Steve N.
-
OR5 does not need +5
OR6 will need it.
Steve N.
Now that is a surprise. Most of the high-end converters (and DACs that make an attempt to take USB seriously) make a point to completely avoid any reliance on the Vbus because it's full of noisy crap. That also lets you cut the supply off using the switch on the SoTM card, or the Short Block, etc. I've always knocked Berkeley for powering the receiver half of their Alpha USB using the Vbus, even if its supposedly separated from the output half via opto-isolators or however they did it.
I've also seen plenty of claims about devices that do use Vbus power being able to "clean it up" via regulators, and it never works. All of them are greatly improved when the Vbus line is substituted with another 5V supply from a battery, or the iUSB, or similar devices.
What's the reason for the change?
-
Now that is a surprise. Most of the high-end converters (and DACs that make an attempt to take USB seriously) make a point to completely avoid any reliance on the Vbus because it's full of noisy crap. That also lets you cut the supply off using the switch on the SoTM card, or the Short Block, etc. I've always knocked Berkeley for powering the receiver half of their Alpha USB using the Vbus, even if its supposedly separated from the output half via opto-isolators or however they did it.
I've also seen plenty of claims about devices that do use Vbus power being able to "clean it up" via regulators, and it never works. All of them are greatly improved when the Vbus line is substituted with another 5V supply from a battery, or the iUSB, or similar devices.
What's the reason for the change?
Necessaryfor some of thecircuitsforgalvanIc isolaton. Will not affect jitter, only improve it.
Steve N.
-
OR5 does not need +5
OR6 will need it.
Steve N.
I agree with DaveBSC on this. This is strange. Why go backwards?
-
I agree with DaveBSC on this. This is strange. Why go backwards?
I don't consider it a step backwards. With galvanic isolation, the Short-Block will not be necessary. Galvanic isolation is a bit better than a filter I predict. Jitter will be just as low as the OR5.
Steve N.
-
Alpha guts exposed. Apparently their method of isolating the input side of the Alpha USB from the output is an Analog Devices ADuM chip, plus a shield that's part of the chassis. The clocks are Crystek CCHD-957s. Steve, I'm curious if you think the OR6 will be improved by adding something like the iUSB or a 5V battery inplace of computer power. It seems to make a significant improvement in every other design I've seen that uses Vbus power, including those with galvanic isolation.
(http://imageshack.us/a/img145/1596/alphausb4.jpg)
-
There are significant differences in my design. Looking at the BADA design, I don't see any signs of true reclocking across the isolation interface.
I will be using a faster isolation chip too.
I fully expect the +5V in the cable to not matter and the cable will not matter either. This is what I already have with my Synchro-Mesh, so I know it can be accomplished.
Steve N.
-
So let me make sure I understand here.
There will be no need for my SOtM PCIe USB card to have it's own power supply? And no need for a fancy pants USB cable?
Also will the OR6 still be housed in a black enclosure? Or will there be a choice of colors?
-
So let me make sure I understand here.
There will be no need for my SOtM PCIe USB card to have it's own power supply? And no need for a fancy pants USB cable?
Also will the OR6 still be housed in a black enclosure? Or will there be a choice of colors?
Right, the USB interface should not matter anymore. I plan to offer the OR6 in a silver chassis with the Overdrive type front panel.
Steve N.
-
Hi Steve,
OR6 sounds very promising if it can finally eliminate the effects of USB circuitry and cabling.
Will it use the same outboard power supply as OR5?
Best regards,
Jean-Pierre
-
Hi Steve,
OR6 sounds very promising if it can finally eliminate the effects of USB circuitry and cabling.
Will it use the same outboard power supply as OR5?
Best regards,
Jean-Pierre
Same supply. Plan is that OR5 will be upgradable.
Steve N.
-
Steve - I am thinking of replacing the pulse transformer on my DAC, which is not one of your products. How do you evaluate pulse transformers? Do you have any recommendations as to readily-available pulse transformers, such as the Lundahls or those from Scientific Conversion, Inc?
-
Steve - I am thinking of replacing the pulse transformer on my DAC, which is not one of your products. How do you evaluate pulse transformers? Do you have any recommendations as to readily-available pulse transformers, such as the Lundahls or those from Scientific Conversion, Inc?
Both of these are good quality. The important thing is to replace it with the same type, as in 1:1. If it has a shield, this must be grounded.
Most of the time, the bigger problem is that the resistors used to match impedance are the wrong values, or the resistor network is not an optimum one.
Steve N.
-
Hi,
Does anyone know if the Apogee Minidac can be used with the SM with OTL mod? I searched the web but couldn't find any info on whether the minidac has input transformers.
I'm about to get the SM but unsure if I can go with OTL option.
Thanks in advance for any advice
-
I recently sent my OR5 to Steve for the OTL mod and it does not disappoint. The improvements are easily as significant as adding the Dynamo power supply. Depth, layering, separation, (insert buzzword here), all took a step forward. I most appreciate the tonal realism. Brass instruments are now extremely realistic. Also, micro dynamics exhibit finer gradation which is particularly noticeable on piano.
My Aqua La Scala Optologic sounds so fantastic fed by the OR5 OTL that I haven't even been tempted to try the Aqua's onboard USB. You don't need an expensive DAC to hear the differences, though. I also own an uber-modded Eastern Electric DSD Supreme and the OTL mod is plainly audible there, too.
If you are on the fence about whether the OTL mod is worth it, I can assure that it is. :thumb:
Jake