Wadia 170iTransport - To mod, or not to mod?

It's been about a year now with my iTransport so I thought it was time to research mods and get opinions, recommendations.

I became interested after recently seeing the CIAudio VDC 9.0 power supply. Would this make a difference though since I plug mine into a Walker VelocitorS already? It's almost the price of the iTransport too. Plus it would require another power cord.

I'm sure there's various internal parts that would benefit, but the only other mod I had considered was upgrading the SPDIF RCA jack to a WBT NextGen Ag. I wonder if Wadia has made any changes since mine?

The first mod I would make is to upgrade to the iTouch. The solid state drive in it makes no noise unlike the iPod Classic which uses a standard hard drive. This will improve sound quality immediately.

I am having my Wadia upgraded by ASI technologies in about a week. I will let you know how it turns out. Here is the link http://www.asi-tek.com/wadia2.html

I am getting the standard mod package and the DEXA Neutron Star Flagship Clock Upgrade.

Here's a different opinion I received from Empirical Audio;

The problem with modding the iTransport is that is uses the PCM270X chip from TI. This chip, even with the best clock on the planet is very jittery. I should know, I had products based on it years ago. The AirPort Express uses it also.

The best mod for an iTransport is no mod at all. Add an external reclocker like the Pace-Car 2. This will outperfrom by a long shot any mod that you care to do to it. Also, once you put money into mods, the mods become worthless. You never get your money out of them. The Pace-Car on the other hand has a great resale and lasts maybe a day on Audiogon.
Nrostov go to computeraudiophile.com type in teardown wadia i transport and click search. Chris of computeraudiophile does a complete review of the wadia i170 and takes it apart to see whats in it. You can also read the posted commets by empirical audio about the pcm270x chip found in the wadia and J. gordan Rankin of wavelength audio said " the ipod is a great product but it's a mobile personal player. Use as a high end transport is a waste of time" It seems to me that many of these guys who design digital gear say that putting in any sort of clock into the itransport is a wast of money, your better of on getting an outboard clock. I hope that your asi mod is as good as they say however i think is a big rip off.
I posted this tear-down thread from computeraudiophile.com that Usarmyvet91 is referring to in the other 'msb ilink vs. Wadia 170 ipd dock' thread. I'll post it again here for the benefit others:

The guy at ASI is a good tech but a poor businessman.Naturally YMMV,Bob
Bombaywalla thx for the info. computeraudiophile is a good site for the latest in computer audio info.

I have had nothing but good experiences with Doug at ASi. In what way is he a poor businessman?
Nrostov i should't have said i think asi mods are a rip off because i have not listen to their mods however people that i have spoken to in the audio business tell me that putting any kind of clocks really don't work. I guess the only way to find out is when you get your back.
Several of the people saying that putting clocks inside the Wadia will do nothing are the same people selling clocks to put outside the Wadia. Do these people have a reasonable explanation how a clock inside the Wadia is worthless, but outside is pure magic? I would like to know, but haven't seen an explanation that makes sense yet.
Noshortcuts your right the couple of people that i have talked to in the mod and audio business tell me that clocks will not work inside of the wadia. Then turn around and try to sell me their outboard jitter device that has a clock in it, go figure.
Noshortcuts, Usarmyvet91
OK, here is how I understand it (an expert in this matter is free to correct me) - any product that uses the TI PCM27XX 'stereo DAC with USB interface' IC (the Wadia 170i uses the TI2705) inherently suffers from high(er) jitter because the PCM27XX family of ICs uses what is called adaptive clock recovery. I.E. the PCM27XX IC uses each 1mS burst of data on the USB to extract the clock from the data. The inherent flaw w/ this methodology is that
* the computer is not always punctual in comanding the iPod to send a 1ms burst of data, which means that the recovered clock freq can drift in the meantime
* there is a lot of interference in the total system & this noise can be injected into the data being recovered by the PCM27XX IC.
Thus the quality of the recovered clock signal is as good as the overall environment inside the 170i & basically, there is no fixed clock reference. The PCM27XX IC uses a 12MHz xtal oscillator (which you can see on the PCB if you open the 170i unit) but this clock is used for the clock recovery ckt. It is not used directly for the on-chip DAC. Once the clock is recovered, it is fed to an analog PLL as a reference freq & the analog PLL locks its VCO to this reference. The analog PLL VCO output is used as a clock to the on-chip DAC. PLLs are very useful in cleaning up "dirty" signals hence a lot of the phase noise of the recovered clock reference can be reduced. However, there is a limit to the amount of clean-up - the analog PLL VCO will somewhat track its noisy reference signal (depending on what the analog PLL bandwidth is). This will show up a high(er) jitter on the output digital stream.
What the modifying houses are doing is that they are improving the 12MHz clock to a Superclock (at high cost to the user). Yes, there is some benefit to making this 12MHz clock cleaner BUT it does not tackle the central issue of adaptive clock recovery using the USB data stream. Adaptive clock recovery is the central theme to the PCM27XX family operation & since it creates a jittery reference clock, the end result is jittery digital data out. So, let us say that the ROI of this mod is (very) low.

What the people, who want to sell you re-clockers, are suggesting is that you create a 2 clock system - one clock (the Wadia's) will be high(er) jitter & the 2nd clock (the re-clocker's) will be a precision clock.
In effect, let the 170i do its adaptive clock recovery thing & create a jittery digital data output stream. Then, feed this jittery digital data stream into the re-clocker running off a precision clock. The re-clocker, in all probability, has a FIFO (first-in, first-out) buffer wherein the data comes in at the jittery clock rate & gets pulled out at the precision clock rate. This is an Asynchronous Rate Conversion which converts the digital data stream from the jittery clock domain to the precision clock domain. Thus, the digital data at the re-clocker's output is very low jitter. This can now be fed into a DAC of your choice & the sonics should be much improved.
(in contrast there is no such 2 clock system native to the PCM27XX IC family so the user is stuck with the jittery recovered clock. Hence there is no method in the PCM27XX to transfer the data to a clean clock domain).
Bombaywalla - your explanation of the problems with the PCM270X chips is spot-on, however it is not fair to say that all chips that use adaptive mode have high jitter. This is simply not the case. The problem is specific to the PCM270X. I have a lot of experience trying to reduce jitter of this chip and finally gave up.

Steve N.
Empirical Audio
Bombaywalla it sounds like from what your said, the best way to improve the sound/jitter of the wadia i170 is to use a good outboard clock. I know empricial audio has one called pace car 2 very good reviews, i think it can cost as much as 2,000 if you get it fully loaded.
Appreciate your feedback re. the problem being specific to the TI PCM270X chipset.

Just so that you know my explanation above was in response to your following comment:
03-19-09: Usarmyvet91: Noshortcuts your right the couple of people that i have talked to in the mod and audio business tell me that clocks will not work inside of the wadia. Then turn around and try to sell me their outboard jitter device that has a clock in it, go figure.
It is not that I want to buy a re-clocker.

"No mod, is good mod".

Why not replace that 'jittery' TI chip [PCM270X] then, or is that what the ASI mod does? Why did Wadia use this chip (savings) if it's known to be 'jittery'?

After some reading I don't think I'm going to mod my iTransport, at least not yet. Wadia will probably have a new one soon anyhow. You know how it is with computer products; "obsolete before it's released".

I didn't know that the iPod Touch had a SSD. That would be better, but the limited capacity keeps me away. My whole CD library is on my 160 GB Classic iPod in Apple Lossless (over 500 CD's and still some room to spare). Buying multiple iPod Touch's is cost prohibitive so you don't have to dock it for other music.

And as far as an outboard clock, $1250 for the Pace-Car 2 is too much. When mods start to cost 4x as much as the product they are modding then you need a better product first.

I'm still curious if any one has tried the CIAudio VDC 9.0 power supply and what they thought. Would it even matter since mine is plugged into a Walker VelocitorS?

With regards to USB DAC's; I auditioned a number of them in my system ($100 to $3500), including the 'Brick' and 'Cosecant v2'. I have the iTransport, which tells you what I thought. I also tried the SB3 before that and preferred it to the USB DAC's but it had constant drop-out issues. That Weiss Minerva FW DAC looks cool. But then I already have a superb DAC.
Why not replace that 'jittery' TI chip [PCM270X] then, or is that what the ASI mod does?
Ach, can't do that! the whole 170i is built around the PCM270X IC. You remove this IC & you basically have nothing!
I believe that the better thing to do is to re-clock the digital signal. You can use more modest re-clockers such as Monarchy DIP, GW Labs, Genesis Digital Lens. Some of these are available used.

No, the ASi mods are quite extensive but it does not replace the PCM270X IC. The ASi mods offer upgrading caps & voltage regulators, replacing the clock with a Superclock, chassis damping, better quality connectors, etc, etc. You can read more on their website. I don't have the address handy but Google it.

Why did Wadia use this chip (savings) if it's known to be 'jittery'?
yes, I'm sure that the end cost must have played a part in selecting this commodity IC. The 170i is a $380 docking station for a $250 iPod. The prices of both items match - people buying the iPod would consider the 170i as a mate. What if the 170i cost $1250 (like the Pace Car 2) - would an iPod buyer consider it as favourably as he would a $380 170i? Some would but most will not!

That Weiss Minerva FW DAC looks cool
yup! have a couple friends that own it. this DAC can go all the way to 192KHz so it can playback standard redbook & upsampled redbook. Seems to have all the flexibility that one would need today. It's the FireWire connection that allows it to support 192KHz.
Thanks, Bombaywalla

I agree, most iPod users would not see the iTransport as favorable a mate if priced like the Pace Car 2. But to me the iTransport was meant for Audiophiles, not MP3 listeners. Wadia should [have] offer a 'cost no object' version.

The GW Labs DSP is more affordable. But the problem I have with adding an outboard re-clocker is the need for another digital cable to match the one I have, as well as another power cord, and raising the cost. I also want to keep my system simple. That's one aspect of the 'computer audio' DIY I've never liked - all those extra parts, and wires, and connectors, and plugs, and cords,... aaaaggh! Doesn't work with my OCD perfectionism. ;-) Not the kind of high-end audio I want.

The Minerva is intriguing (I could use my iMac via Fire Wire), but I think my Reimyo DAP-777 is still a strong contender. I also realized from my music server trials that it takes a special set up (DAC) to match what I had with my previous CDP. The USB DAC's I auditioned just weren't delivering the sound I was accustom to. Fortunately the Reimyo DAP and iTransport did just that, and more.

I admit though, the rest of my system does make up for what the iTransport/iPod lacks so there's room for improvement at the source. It's that kind of situation where you'd have to hear it to know it. But I knew from the USB DAC's I auditioned that I'd have to find a superb DAC if I wanted to hear what I was used to hearing before. It's not as simple as getting a music server as many seem to think/imply. You can't match what you had unless it's the same DAC, or better; i.e, buying the Olive music server would not be as good unless it was running through my DAC, or it's internal DAC was comparable to what I had.

Their are quite a few companies doing mods: Great northern sound co. i have one, Hot rod audio mods, asi and auidocom-uk.com my mod from GNS was around $750 that was including the wadia i170. Some mods can run as high as $1,800 from asi they claim their modded wadia can sound as good as the best cd transports from esoteric and cec.

seems that some guys have the same ideas and questions, that i have.
Latest review from german "Stereoplay" testing the standard Wadia with their reference DAC, the Accustic Arts Tube-DAC II SE(7000Euro) looks not so bad. They compared the 170i(Ipod Touch) with the 6900Euro Acustic Arts Drive II SE and the result was, that each of the both have advantages in some sonic aspekts, but they cannot prefer one of them. Having a look upon the price, that´s an impressiv result for our little friend, from my point of view.
I think Bombaywalla exactly knows of what he´s speaking, and the result of this review with the external Clock/DAC tells the same story.
Thanks a lot !
I'd focus my attention on the clock and DAC downstream of the Wadia. IMHO, it only makes sense to mod the Wadia if you use its analog outputs.

I'm using mine with the Playback Designs MPS-5 as the DAC. The designer claims zero jitter and I can't hear anything to dispute this. When I compare iPod to Wadia to PD output to the PD using it's internal transport. If your DAC or separate clock is going to reclock the Wadia's output, then the ICs and connections make little or no difference, IME.

I made up my mind: TADAC
I'll let you know how it goes when I get it here and up and running.

i just had a look upon what the modifiers do with the 170i.
My opinion, and please correct me if you think it´s wrong, is, that to give the wadia a better POWERUNIT, a better PLUG(WBT Next Gen?) to the digital output and a better DIG.CABLE, may also bring a better performance using a external DAC, cause the incoming digital signal should be less jittery , to make the job a little bit easier for your converter.
ALL THE OTHER MODIFICATIONS, i think, are only intersting for people who have no digital input in their other equipement, cause it only makes the internal DAC and it´s analog output-transformer better.
I´m very interested in the experiances of the people, who have the mods on their player, using an additional DAC.
Logical thinking on good sound, very often seems not the wright way to improve............

In some aspekts of High End i was wrong over decades.

In the result, today i listen to everthing i read, even it seems to be impossible.

hello everyone,

if you click on my system you will see my comments on the upgrade i did to my wadia.
Wow, the TADAC solved everything I wanted solved in my system.

I had Wadia > Onkyo 885 > Sunfire TGA-7400 > Salk SongTowers.

I wanted to improve the already great sounding digital path of music in 2 channel audio while keeping it all user friendly (WAF).

I added a TADAC with HT bypass: Onkyo pr-sc885 Pre > TADAC > Sunfire TGA-7400 > bi-wired to Salk SongTowers (because TGA-7400 has current source and voltage source outputs).

The TADAC, as far as I know, is the only DAC with HT bypass available. It also is a superb preamp, re-clocks the incoming music data (de-jittering), and offers beautiful tube sound.

Thumbs up TADAC: Wow, wow, wow.
I thought my system sounded good before .

Improvements: detail, texture, separation, LIVE-liness !!!


* Sound, sound, sound.
* HT bypass working flawlessly. The TADAC can be ON or OFF and HTbypass works perfectly.
* No problems, hum, difficulties.
* It is all working via Harmony remote (turn on Activity "Digital Music" and the Onkyo 885 preamp shuts off and the Harmony uses the TADAC's volume control and mute. Turn on a DVD or TV, etc., and the Onkyo comes on and feeds front channels though the TADAC which has stayed on but the music was stopped automatically.
* Sound, sound, sound.


* It's not the prettiest.
* It does not power on/off via remote but by a large toggle on the rear.
* To keep the signal path short, the outputs do not mute when the headphone jack is used. You have to unplug the outputs to use headphones. Mine are hard to reach so it's a good thing I rarely want to use headphones. When I do, maybe it will be extra great with the short signal path....

Last positive: Paul is great to order from. He designs and builds the TADAC and he answers all questions via email.

Last negative: Paul has stopped building the TADAC but the good news is that he is building a new "PreDAC" which I assume will be similar but better?!

For me this answers the question to mod or not. At least for now. The music is so much improved.
I need to fix something in my last post (and don't see a way to edit).

After adding the TADAC, the stereo path is: WADIA/Ipod (not Onkyo) > TADAC > Sunfire TGA-7400 > bi-wired to Salk SongTowers (because TGA-7400 has current source and voltage source outputs).

I will continue to watch for other iTransport improvements such as Nrostov's great results with Wadia mods (linked above). Keeps me wondering how much better SQ can get?

One mod I didn't get because I didn't feel like spending the money was to mod the Wadia so that it is battery powered. Even though I am using a Shunyata python as a power cord, and running it through a Shunyata V-Ray, I would imagine taking it completely off the electrical grid would be an improvement. Given my setup though I don't know how much of an improvement it would be. Is say a 3% improvement in sound quality worth an extra $695? In these tougher economic times these are the things I think about. Even though I can afford it I always ask is it worth the money.
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