[welwynnick]

Hello Steve,

I have been spending hours reading your website and Audio Circles Forum, and I’m still slightly confused by your mods and products, but I’m very intrigued by what I could do with my audio.  

I gather you do I2S modifications to certain DACs, and enhancements to various quality amplifiers, including the Pioneer SA-XR series.  Well, I have a Pioneer DV-47Avi player and Sony TA-DA9000ES class D amplifier, connected by i-Link.

I’m very happy with the amp, but it does seem particular about which input is used - I-link is better than SPDIF, is better than analogue. This is a good stock combo, but I was wondering if there is potential to improve it with a direct I2S interface and avoid any DAC?  A long shot, but what do you think?

Best regards,  Nick

[audioengr]

Hello Steve,

I have been spending hours reading your website and Audio Circles Forum, and I’m still slightly confused by your mods and products, but I’m very intrigued by what I could do with my audio.  

I gather you do I2S modifications to certain DACs, and enhancements to various quality amplifiers, including the Pioneer SA-XR series.  Well, I have a Pioneer DV-47Avi player and Sony TA-DA9000ES class D amplifier, connected by i-Link.

I’m very happy with the amp, but it does seem particular abou ...

An I2S interface would probably improve it, however it is not all that easy to do a custom installation, and it can be expensive, many times the price of the Sony.  It is not simply a matter of bringing-out the I2S signals.  The sample rate must usually be decoded and there must be some kind of mute mechanism or damage to speakers can occur.  The I2S signals must be terminated properly and a receiver used.  The other inputs will be dead unless a selector is inserted.  If all of this circuitry is added it usually means a custom circuit-board, sometimes a flex-circuit, which can cost $200 each in small quantities.  Custom designs like this can cost upwards of $4-5K, particularly if it is a one-off.

I have focused on adding or modifying I2S on several DAC's including the Benchmark DAC-1, the Northstar and the Lite DAC-60.  I also have a design for the DEQX and may have one for the TacT as well in the future.  These are high-performance units and I will be doing many of them, so it makes it worthwhile to design custom boards for them.  If I do many of them, then I can order dozens of circuit boards and the cost comes down to a reasonable amount, like $500 for the Benchmark.

Steve N.

[brj]

I have focused on adding or modifying I2S on several DAC's including the Benchmark DAC-1, the Northstar and the Lite DAC-60.

You have a mod package including I2S interface for the DAC-60?  Are there details and pricing posted anywhere?

Thanks!

[welwynnick]

Thanks Steve, I was afraid of that, but I appreciate your answer.  I know of one person who has an I2S modified DVD player & DAC, and he really rates it.  Otherwise, it sounds like a home entertainment PC and an Off-ramp is the solution for an "I2S" source.

Anyway, my other question was going to be, given that you do some much modification work, why don't you just design and build a DAC yourself?  Quite an undertaking, but you must really know what makes them tick by now!  And it could be designed around spdif, I2S and USB inputs from the outset!

I bet you wouldn't have too many problems with economies of scale with that!

Best regards,   Nick

[brj]

Anyway, my other question was going to be, given that you do some much modification work, why don't you just design and build a DAC yourself?

He has already announced his intention to release an Emperical Audio USB DAC.  I don't know that he has mentioned details yet, but it has been alluded to a few times.

From his website:

New Products under development:
 USB interface for DEQX - first one complete. Flex-circuit for additional ones being fabricated.
Off-Ramp WIFI - first proto-board version shipped. Circuit board in house and 2 being assembled. S/PDIF, AES or I2S outputs.
Off-Ramp Turbo2 - First protos being fabricated - expected 6/22/05
USB DAC - Q4 2006

I confess that I'd also be interested in some details and pricing estimates, however....

[audioengr]

I have focused on adding or modifying I2S on several DAC's including the Benchmark DAC-1, the Northstar and the Lite DAC-60.

You have a mod package including I2S interface for the DAC-60?  Are there details and pricing posted anywhere?

Thanks!

No details posted yet because I'm toying with the idea of doing my own USB tubeDAC based on the DAC-60.  I have designed a flex-circuit for the I2S interface that can be used in it and I can remove the front panel and the optional XLR backpanel and get these further machined for the USB interface and my logo on the front panel.  I would do the DAC mods, install the USB interface and I2S interface and then replace the front panel.  Have no idea what the pricing would be.  The first one that I "wire-modded" was $2560.00 not including the DAC, which was already modded by Sonicraft.

Steve N.

[audioengr]

Thanks Steve, I was afraid of that, but I appreciate your answer.  I know of one person who has an I2S modified DVD player & DAC, and he really rates it.  Otherwise, it sounds like a home entertainment PC and an Off-ramp is the solution for an "I2S" source.

Anyway, my other question was going to be, given that you do some much modification work, why don't you just design and build a DAC yourself?  Quite an undertaking, but you must really know what makes them tick by now!  And it could be ...

Nick - it's in the works. In the meantime I have a dozen other projects on my plate including:

DEQX USB interface
Lite DAC-60 USB interface
Off-Ramp Turbo2
Rev 2 Off-Ramp I2S
Off-Ramp WIFI - based on AirPort Express - S/PDIF and I2S
Northstar Transport and DAC mods

Steve N.

[welwynnick]

Thanks for the good replies, guys.

I'm still struggling to see how I2S can fit in.  I understand what it achieves and how it does, but on a practical note how do you implement it?   For convenience I would prefer to use a CD player, but they are not exactly thick on the ground.  

After a bit of research (some of which led me straight back here) I found out that Audio Alchemy produced some players that had I2S outptus.  I'm a bit surprised that i haven't seen much mention of them in these pages, though.   Does anyone have any experience of using one with a recent I2S enabled DAC?

Cheers,   Nick

[audioengr]

Thanks for the good replies, guys.

I'm still struggling to see how I2S can fit in.  I understand what it achieves and how it does, but on a practical note how do you implement it?   For convenience I would prefer to use a CD player, but they are not exactly thick on the ground.  

After a bit of research (some of which led me straight back here) I found out that Audio Alchemy produced some players that had I2S outptus.  I'm a bit surprised that i haven't seen much mention of them in these pages, thoug ...

Yes, I am collaborating with Bauls Audio that sells Bastani speakers to do some I2S interfaces.  They have been using the Alchemy Transport with my P-3A DAC for a while now.  We are trying to mod the Northstar Transport and 192 DAC so that it will be suitable for the Bastanis.  The Northstar Transport is compatible with my DAC's, with a minor mod to it and a custom cable.  It outputs 24/192 which is compatible with the Northstar and the Benchmark DAC-1.  Outstanding sound with the Northstar transport driving Benchmark DAC-1 with I2S.

Steve N.

[welwynnick]

The Northstar Transport is compatible with my DAC's, with a minor mod to it and a custom cable.  It outputs 24/192 which is compatible with the Northstar and the Benchmark DAC-1.  Outstanding sound with the Northstar transport driving Benchmark DAC-1 with I2S.

Steve N.

Thanks, that's what I was hoping to hear.  

How does it compare with PC audio / Off-Ramp Turbo / I2S Benchmark DAC?

[audioengr]

The Northstar Transport is compatible with my DAC's, with a minor mod to it and a custom cable.  It outputs 24/192 which is compatible with the Northstar and the Benchmark DAC-1.  Outstanding sound with the Northstar transport driving Benchmark DAC-1 with I2S.

Steve N.

Thanks, that's what I was hoping to hear.  

How does it compare with PC audio / Off-Ramp Turbo / I2S Benchmark DAC?

I think it is very close, although the jitter is lower with the Off-Ramp I2S and the I2S benchmark DAC-1.  Lowest jitter I have heard in ANY DAC.

Steve N.

[brj]

Steve, do you have a list of the jitter levels for your various mods somewhere, ideally compared to the pre-mod jitter level?

Assuming a highly resolving system, how small of a change in jitter level can a reasonably experienced listener perceive?

Thanks!

[welwynnick]

The answer has probably been staring me in the face for some time now.  I guess I should just get a USB Freeway 2, and connect it directly to the SPDIF in on my amp.  That would work well, wouldn't it?

BTW, I just had a look at the Head Fi site.  They don't seem to think of computer audio as a route to improved sound quality.  It's all snake oil, placebo's, the power of suggestion, that sort of thing.

Maybe I'm just open to suggestion, but I do think amplifiers, transports, power cables and everything in the digital domain does sound different. 

Nick    

[audioengr]

Steve, do you have a list of the jitter levels for your various mods somewhere, ideally compared to the pre-mod jitter level?

Assuming a highly resolving system, how small of a change in jitter level can a reasonably experienced listener perceive?

Thanks!

Beats me.  I only know that I have heard differences that I cannot see with 5 nsec/division resolution on my scope.

[audioengr]

The answer has probably been staring me in the face for some time now.  I guess I should just get a USB Freeway 2, and connect it directly to the SPDIF in on my amp.  That would work well, wouldn't it?

BTW, I just had a look at the Head Fi site.  They don't seem to think of computer audio as a route to improved sound quality.  It's all snake oil, placebo's, the power of suggestion, that sort of thing.

Maybe I'm just open to suggestion, but I do think amplifiers, transports, power cables and everything in the digital domain does sound different. 

Nick    

Yes, the Off-Ramp Turbo 2 would work well.

I believe based on the posts, many of the folks posting on Head-Fi do not have resolving systems and therefore they do not believe that digital makes much difference.  They even seem to believe that Toslink is the best solution for computer audio.    BLAAAAAH!!!

Steve N.

[audioengr]

The Northstar Transport is compatible with my DAC's, with a minor mod to it and a custom cable.  It outputs 24/192 which is compatible with the Northstar and the Benchmark DAC-1.  Outstanding sound with the Northstar transport driving Benchmark DAC-1 with I2S.

Steve N.

Thanks, that's what I was hoping to hear.  

How does it compare with PC audio / Off-Ramp Turbo / I2S Benchmark DAC?

I cannot answer this because I have not heard one completely broken-in.  However, I believe that the Northstar DAC, like the P-3A will not beat the Benchmark, because they both use the older CS4396/7 DAC chip.  The AD1853 in the Benchmark is a superb DAC chip.  Just as good as the BB PCM1704 AK IMO.

Steve N.