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Arcam rPAC Review

post #1 of 24
Thread Starter 

ARCAM rPAC Review

 

 

 

 

 

High Res Pics in Spoiler: (Click to show)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Introduction:

This is Arcam's new rPAC which is their "Personal Audio Converter". It is an all in one headphone amp and DAC with fixed DAC line out options and no need for external power supply. I wish to thank Mr. Follis at A and R Cambridge for leasing me this unit for review.

 

Read the review here:

http://www.pandatechreview.com/arcam-rpac-review/

 

Manufacturer introduction:

 

 

Arcam Website

Meet the award-winning Arcam rPAC, the Personal Audio Converter that will transform your computer-based music - at home, at work, or on the move.

We’re all playing more music from computers - stored on their hard drives or streamed from online services such as Spotify – but Macs and PCs simply aren’t optimised for audio enjoyment.

The rPAC is a pocket-sized solution. It features hi-fi-grade hardware and software engineering, specifically designed to enhance your laptop or desktop listening. From low-bitrate internet radio to better-than-CD-quality downloads, you’ll hear more of the music you love.

And it’s not just about music: the rPAC can boost all your computer entertainment, from gaming and movies to catch-up TV services, such as BBC iPlayer and Sky Go.

Simply connect the rPAC to your computer (Windows XP, 7 or Mac OSX - please note Linux is not supported by the rPAC) using the supplied USB cable, then either on to an audio system via a standard RCA lead (also included), or out to headphones. Lovers of the latter are well served by the rPAC, which features a high-quality headphone amp, complete with volume controls.

It’s that simple. No batteries or mains needed. We even give you a carry case to help you on your way to better audio, anywhere.

 

 


 

Build Quality:

This is got to be one of THE most solid devices I have laid hands on. It is compact and is almost fully encased in a metal body. The top and sides are full metal with a slight rubber/plastic coating on top. The bottom is rubber with a metal plate(thin) in the rubber itself.

 

 (Click to enlarge)

 

There is no other word I can say then this is solid. It is average on scuffing, nothing too special but not super easy either. And weighs a lot more than you would think when you first saw it and connected the build with plastic. You and I were wrong. However because it is so encased in metal and heavy for a device of this size, I would say that this is NOT shock resistant in any way shape or form and should be handled with caution despite good stands and holdings as you can see.

 

Also on the build is DIY-ability and or self diagnosing or fixing. Arcam lets you EASILY take this apart. Seriously, if you have a screwdriver then that is it. All you need is to remove the screws that are visible(no hidden ones) and a small slide and bam. You are fine. As this was a lent sample I of course excercised caution. I wasn't going to go full iFixit on a sample like this but I was curious and so checked for hidden screws beneath the tabbed model paper on the bottom and others and took them apart meticulously.

 

 

Accessories:

The rPAC comes with a USB type A to type B cable for your computer or device, an RCA interconnect cable, cloth baggie, thank you card and startup manual

 

 

 

 

 

 

There is nothing out and amazing or anything wrong with the accessories to affect any type of judgement (such as poor quality paper or matierals etc) and so that's about it for this section. Good RCA cable and USB cable.

 

 

 

Usability:

This is what I would call the biggest deciding factor of the rPAC. The sound section below will tell you why but by itself for a $250 device, even with a feature such as asynchronous USB, it isn't going to be worth $250 to many people for what it produces. However combined with all it's uses, depending on who you are. It just may be. The rPAC's main selling point to me is it's combined function and to those that need it. It has a 3.5mm headphone jack out front, that will output audio at the same time with your DAC lined out speakers. This was actually quite nice in my opinion. No switch for DAC fixed line out. It just happens really. Plain and simple. Both outputs continuously output a signal and so you can use both, no need for an extra switch and no. Pulling out your RCA interconnect cable won't give your heapdhone amp a boost in power. Next the rPAC has steps and simple two button volume controls on tops. The steps in my opinion are many and are very low/small changes each step so it may be annoying for those that want to turn it up really fast. You can hold it down and each step that goes, the LED green with blink once, once it reaches max at either end, it stops blinking. You press both + and - at the same time to mute your music and you press either + or - to resume it. Unmuting does not work with pressing both buttons again as the double press seems to just be mapped to a mute function. 

 

The rPAC overal is for someone that has headphones, speakers and likes to take it places, wants a strong build, name they have heard of and like, no hassle of external plugged power and just plug and go simplicity. By itself for each of these at such a price range, the rPAC is a bit hard to swallow but for it's combined usage, I can see many audiophiles or not that want such functions to readily grab this device. 

 

Asynchronous USB:

This unit proudly displays and packs asynchronous USB technology. Asynchronous USB is a standard that says or tries to fix any problems that may occur between device and computer by sending feedback to the computer on if it has received something and everything. This two way connection is said to improve audio quality by being more timed and set and can lead to less errors and also better playback. With my testing, A-USB was smoother and took longer to play or scroll through a song with. On units with A-USB, scrolling/scrubbing through a song was near instantaneous with a small delay and then playing. This delay was more apparent on the rPAC by about half a second and the playing and stopping of a song with Foobar using WASAPI was also more delayed which I guess I'll attribute to the A-USB. Overall this technology is becomming more mainstream with a few popular sub $200 products like the HRT Music streamer II already carrying it along with iBasso's and others. And I honestly can tell you that although the jitter was less pronounced when I scrubbed through a song or paused and played, I could not say I could even "hear" A-USB difference really.

 

 

 


Video Unboxing:

 


Testing Setup:

 

My reference setup will be:

ComputeràS/PDIFàAudio-gd NFB 12.1 Dual Wolfson WM8741 Fixed DAC outàCustom O2 with Burr Brown OPA2228.

700

 

For testing DAC to DAC comparisons it was:

Audio gd NFB 12.1 WM 8740 2.2vRMS Fixed line out-->  Custom O2

 

Arcam rPAC TI/BB PCM5102 2.15vRM Fixed line out--> Custom O2

 

The difference in fixed line out was accounted for.

 

Tested with

Sennheiser HD 215

Ultimate Ears TF10

AKG Q701

Shure SRH440

Ultrasone HFI 580

Sony XB500

Logitech Z623

 


 

Sound Quality:

 

Headphone out:

The sound of the Arcam rPAC as a whole is quite mellow. It doesn’t stand out overly, but nor is it just like flat soda and lifeless. The DAC and amp together gives a soft and not as pronounced but more mixed in low frequency bass hits. It is noticeable however that the rPAC as a whole however does have nice staging that is not visible on many other units which quite surpised me. As a whole the staging although it did have a more pulled back and surround kind of effect was still burdened by it’s amplifier section.  A few other things were that on times when the song would get into a very emotional or violent moment be a quickening and sudden drop of bass and quickening of tempo or massive highs, the rPAC would in a sense quiver delivering an ill sound that can only be described as unmatched. Where the highs wouldn’t exactly go to where  I want and the bass would have a slight muddy upslur instead of a steady and smooth transition. The lower frequency range of the rPAC unit is also not as drastic or as welcoming as I would have liked. The bass was a bit muddy and didn’t exactly punch with not a whole lot of detail to it. Adequate depth of the bass was there though.

 

The rPAC’s sound has good staging but in the end is still burdened by it’s lack of actual depth to the actual contents of the song. The highs weren’t harsh which were good but they were a bit overly sharp in the sense that the high frequency piercings would linger a bit after or had trouble “dropping” and keeping with the rest of the song at times and smoothing out. The highs would also constantly run into the vocals and mids mixing up the upper and center mids and muddying them up or distorting them.

 

DAC Out:

Basically as a whole unit, the rPAC does have a few sonic ills to be noted but can also be forgived, as I will get to later on. The majority of the rPAC’s ills actually stage from the amplifier section of the unit and how it is and on purpose or by design underpowered and also not of much high end. This was confirmed by using DAC out of the rPAC into the reference amp of this price range, the Objective 2 of which mine is a custom one made for high performance desk use with a Burr Brown op amp, RCA in, quarter inch out and various gains and JRC NJM4556. I used the DAC out of the Arcam rPAC into the O2 and also used the DAC out of the Audio Gd NFB 12.1 into the O2 to compare a popular desktop unit the Audio gd to the rPAC.  Both and all units were at around the same price range. 

The results came back were as I expected with most of the ills of the device stemming directly from it’s amplifier stage. The staging that I noticed and liked in the rPAC was still there and even better and more pronounced and clear and detailed and the qualms for the most part were less pronounced was gone. The vocals were warmer and more forward and more detailed. The highs were smoothed out but yet again another problem came and it was that the highs were noticeably more fatiguing now. They were smoothed out by a good amount while still maintaining that sharpness but it did have some fatigue in them when listening now.


 

 

Overall headphone out:

 

Highs:

Sharp but is sonically problematic. The highs are nice and sharp but it gets very jumpy around in that range where it wouldn’t smooth out and go as the song wanted to and would constantly muddy up the vocals and mids. They weren’t harsh but nor were they detailed. I guess you can say it was a bit everywhere in it’s own confined space. They were still highly useable though as they were still sharp and could still pierce through songs.

Mids and vocals:

Prominent with adequate depth and separation. Staging of the separation is also a nice feature and add on. Not as natural as I would like them to be however as they were a bit thin compared to other units.  I would call this section to be a quite normal really. The guitars and vocals and other instruments had a nice and warm sound that wasn’t too warm or metallic. Nothing wrong with them, but nothing exciting with them either. They don’t have an affinity for male or female vocals, of European/American or Asian accents.

 

Lows:

The lows of this song have a good amount of depth and kick. Able to kick with the song without overpowering or being too little. However like any amp. It’s only easy to tell apart if that amp has problems with it’s design or implementation which this one didn’t have so really it’s nothing special past many out there. However what was easy to spot out was the punch of the lows of the unit. Which wasn’t very punchy. A bit muddy actually, more comparable to something for subs than a headphone. They didn’t have the detail or actual “oomph” to go along with many songs as with comparable units.

 

Conclusion:

The rPAC’s headphone out is underpowered by design but does have enough juice for most headphones, although most of the ones that it does have juice is, is below the devices own price range. Driveability is not 100% proportional to price but it is something that does have a relationship with and most won’t have headphones past the price of their amp and DAC at this price point.

The rPAC is underpowered or doesn’t have enough for many reference class headphones at this price because it uses USB for power. Consumer USB ports generally give out 500mA’s of power so the rPAC has to be designed to be in those limits for both the amp, DAC and other lighting and

components on it.

 

The sonic qualities of the rPac are ok for the price. Nothing special besides it’s staging that isn’t very enticing with this section. Some sonic problems however do put a damper on thigns such as a mellow sub detailed low frequency response and extension and a high frequency range that can muddy and lose control easily. Of course these are still better than a $20 device, one should be note all these sayings on the device are price related as I wouldn’t and can’t test and compare the rPAC to a thousand dollar popular device as I could probably call everything out then as can the rPAC to other devices at another price point.


Overall DAC out:

 

Highs:

 Take 75% of the qualms of the previous section and remove it and add some others and that’s about it. The highs have signifigantly improved, the highs of course are still in their confined area but this time don’t muddy up the mids (for the most part) and is for the most part smoother than before. It is still sharp and piercing with a nice new revitalizing of detail but also a new revitalized fatigue came with it as well. IT’s a lot nicer but also a bit more fatiguing to the ears.

 

Mids and Vocals:

They were largely unchanged but now instead of normal with problems are just normal. They are more pronounced and detailed with a bit more depth. The upper mids that had problems before due to mingling with the uncertain highs are for the most part rectified with this output.

 Seperation and spatial have and are the biggest things anyone will notice. The separation was improved as other sectors before were being muddied up making it hard to even tell what was separate at some parts.  The spatial aspect is also improved and is something you would want for your speakers or even games.

 

Lows:

They are more detailed with a lot more body and punch than before but still falling short of the Dual WM8741 Wolfson Flagships found in the Audio gd. Again the lows in my opinion still hold more for those with subs as they although aren’t punchy, do have more buddy and the “oomph” that you would want with a sub.

 

Conclusion:

DAC fixed line out on the rPAC is signifigantly better than the headphone out. It truly shows off the spatial object placements that the rPAC has. This is not a hear it and it is there aspect as much as it is one that you hear after being tuned to it and comparing. IT is subtle but there and a good add on. I will more or less say that the DAC out encompasses exactly what Arcam wanted, DAC lineing out to speakers with sub units. If the headphone out was like the DAC out with the O2 then this would be a very good device for many.

 


 

Overall Conclusion:

The Arcam rPAC is a very interesting unit, it packs Asynchronous USB, headphone out, no external power source, RCA fixed line out, stepped buttons, and good build in all the same unit which is farily compact at such a price. I would not recommend this device as a desktop unit alone for headphone audiophile's as there are many other that do it's job a multitude of times better but for one that can use all it's functions, this may be a good unit for you. It continuously outputs a singal to both RCA line out and headphone out allowing for ease of use and plug and play without affecting sound. It is small with a good build and only requires the USB cable it comes with for power. This unit is somewhat of a home entertainement unit you can bring around everywhere for your or your friends speaker setups. Just plug into your computer and then into your speaker or recievers and boom. Good sound with a good build, wherever you go. A few other devices from FiiO like the E7 and E17 can line out their WM8740's for the same purpose and are even cheaper but I was not able to test them at this time for their DAC out sound.

 

All in all, I would only recommend this device to those that have read this review and know what they are getting and can put this device to good use. I can imagine someone picking this up and taking it to a next location and simply plugging it in. With it's Asynchronous USB features that some tout is better than optical or coaxil S/PDIF with even less jitter. The value of this device for those that can use it is high, but for those that just want an headphone amp and DAC as this headphone forum usually is more inclined towards, it won't score as high there.

 

Ratings:

Audio/Sonic Quality headphone out: 6.5/10

Audio/Sonic Quality DAC out: 8.5/10

Features: 9/10

Build:10/10

Usability: 9/10

Value:8.5/10

 

These scores are based on price.

 

 

Specs:

 

 

Arcam Site
  • DAC - TI PCM5102
  • Input - USB (Asynchronus)
  • Frequency response - 10Hz — 20kHz, ±0.1dB
  • Total Harmonic Distortion + Noise - 0.002%
  • Signal-to-noise ratio (A –Weighted) - 106dB (24-bit)
  • Line output level - 2.15Vrms
  • Supported sample rates - 44.1kHz, 48kHz, 88.2kHz, 96kHz
  • Bit depth - 16-bit, 24-bit
  • Headphone output power - 138mW
  • Headphone signal-to-noise ratio - 98dB
  • Power requirements - 2.5W max
  • Dimensions (wxdxh, mm) 100 x 62 x 25
  • Weight 300g

 

Pricing:

$250 MSRP; $210 Street

 

 

Again, thank you to Mr. Follis for this lent sample.


Edited by bowei006 - 2/22/14 at 9:38pm
post #2 of 24
Good review.
I've got to say that your writing feels better than it did on previous ones. I don't know what you did, but it feels like a considerable improvement.


Although you used "it's" where you should have used "its" 14 times (yes, I counted) in this review. Don't mix them up!


Also: it would be awesome if you could measure the output impedance of this amp.
It's not difficult and I can teach you how to do it. It'd be a nice addition to future reviews.
post #3 of 24
Thread Starter 
Quote:
Originally Posted by Tilpo View Post

Good review.
I've got to say that your writing feels better than it did on previous ones. I don't know what you did, but it feels like a considerable improvement.
Although you used "it's" where you should have used "its" 14 times (yes, I counted) in this review. Don't mix them up!
Also: it would be awesome if you could measure the output impedance of this amp.
It's not difficult and I can teach you how to do it. It'd be a nice addition to future reviews.

Thanks. I leveled out the Sound Quality section of this one more.

 

Its quite weird that you would even count so man, but that's just how it's device setting usage will have to be done by me.

 

Measure output impendence? Sure that's fine :)

 

I keep a pretty consistent outline for how my reviews like. Only differences is added sections depending on product and that the sound section usually is a bit different.

post #4 of 24
Quote:
Originally Posted by bowei006 View Post

Thanks. I leveled out the Sound Quality section of this one more.

Its quite weird that you would even count so man, but that's just how it's device setting usage will have to be done by me.

Measure output impendence? Sure that's fine smily_headphones1.gif

I keep a pretty consistent outline for how my reviews like. Only differences is added sections depending on product and that the sound section usually is a bit different.

Is this a troll, or do you really not know how to use it correctly?

If you want to measure output impedance you need two things:
A multimeter capable of measuring AC voltage.
A resistor with a resistance of anything between about 10 to 100 ohm. A little more or less is good too.
post #5 of 24
Thread Starter 
Quote:
Originally Posted by Tilpo View Post


Is this a troll, or do you really not know how to use it correctly?
If you want to measure output impedance you need two things:
A multimeter capable of measuring AC voltage.
A resistor with a resistance of anything between about 10 to 100 ohm. A little more or less is good too.

I do know how to use it. Its just too hard.

 

I don't readily have the resistor.....ok I lie. I do but it's not readily availble. Plus it would take too long for me to look through all the color bands to find a 10 ohm one.

post #6 of 24
Quote:
Originally Posted by bowei006 View Post

I do know how to use it. Its just too hard.

I don't readily have the resistor.....ok I lie. I do but it's not readily availble. Plus it would take too long for me to look through all the color bands to find a 10 ohm one.

Why look through the color bands?

It only takes a couple seconds to measure resistance on a multimeter.
post #7 of 24
Thread Starter 
Quote:
Originally Posted by Tilpo View Post


Why look through the color bands?
It only takes a couple seconds to measure resistance on a multimeter.

......good point...but there are so many......

 

Anyway, next steps after that please? confused_face_2.gif

post #8 of 24
Quote:
Originally Posted by bowei006 View Post

......good point...but there are so many......

Anyway, next steps after that please? confused_face_2.gif

Make a sound file with a 60Hz sine wave in Audacity.
Most multimeters are most accurate around these frequencies.

Play back the sine wave at moderate volume. Don't do it on max volume, as that will give you bad measurements, especially if the thing starts clipping.
On most amps something like putting the pot halfway will be fine. Though you can always check by doing measurements once, and then lowering the volume to see if you get the same thing.


Then while the tone is playing, you've got to measure AC voltage between ground and left channel. You can do this by inserting a male-male 3.5mm cable in to the headphone jack. Then measure the voltage between the sleeve and tip (see picture).
You could do it with an RCA cable too, but that will make it harder to add the resistor later. You could also use sleeve and ring, but tip is more convenient. For reference TRS = Tip - Ring - Sleeve = left - right - ground.
Note that you don't HAVE to use alligator clips like I do, but it does make it easier if you have them.



Then note down the reading in to the first box (V1) of this calculator:
http://www.sengpielaudio.com/calculator-InputOutputImpedance.htm

Measure the resistance of the resistor. Or look up whatever it should be from the color codes if you have an imprecise multimeter.
Then put that value in the second box (Rload).

Then add a resistor in between the tip and the sleeve like so:
It may be a bit of a pain to wrap it around like that, but once you've done it once you can reuse the resistor for future measurements.


Then measure the voltage between sleeve and tip a second time like you've done before. Record the reading in the third box (V2) and you're done.



The measurements will be most precise if you use a resistor that is near the output impedance's value.
If you don't notice a difference between the voltage with or without the resistor you can try the following:
- lower the resistors value
- lower or higher the volume (try both)

If there still isn't a difference then that means that the output impedance is very low (<0.1Ohm).
Edited by Tilpo - 8/26/12 at 3:32pm
post #9 of 24
Thread Starter 
Quote:
Originally Posted by Tilpo View Post


Make a sound file with a 60Hz sine wave in Audacity.
Most multimeters are most accurate around these frequencies.
Play back the sine wave at moderate volume. Don't do it on max volume, as that will give you bad measurements, especially if the thing starts clipping.
On most amps something like putting the pot halfway will be fine. Though you can always check by doing measurements once, and then lowering the volume to see if you get the same thing.
Then while the tone is playing, you've got to measure AC voltage between ground and left channel. You can do this by inserting a male-male 3.5mm cable in to the headphone jack. Then measure the voltage between the sleeve and tip (see picture).
You could do it with an RCA cable too, but that will make it harder to add the resistor later. You could also use sleeve and ring, but tip is more convenient. For reference TRS = Tip - Ring - Sleeve = left - right - ground.
Note that you don't HAVE to use alligator clips like I do, but it does make it easier if you have them.

Then note down the reading in to the first box (V1) of this calculator:
http://www.sengpielaudio.com/calculator-InputOutputImpedance.htm
Measure the resistance of the resistor. Or look up whatever it should be from the color codes if you have an imprecise multimeter.
Then put that value in the second box (Rload).
Then add a resistor in between the tip and the sleeve like so:
It may be a bit of a pain to wrap it around like that, but once you've done it once you can reuse the resistor for future measurements.

Then measure the voltage between sleeve and tip a second time like you've done before. Record the reading in the third box (V2) and you're done.
The measurements will be most precise if you use a resistor that is near the output impedance's value.
If you don't notice a difference between the voltage with or without the resistor you can try the following:
- lower the resistors value
- lower or higher the volume (try both)
If there still isn't a difference then that means that the output impedance is very low (<0.1Ohm).

Holy...... I don't even know what to say but I get what you mean..

 

I would ...be less lazy and do it if I had an 10 ohm resistor but you know.

 

Thanks and just so you know, that post of yours is thread worthy in DIY audio or something biggrin.gif

post #10 of 24

I love this DAC. It offers the widest soundstage, awesome highs and low. The rPAc doesn't tale up any desk space either. 

post #11 of 24

Nice review. Thank you very much.

I'll go for an audio-gd instead arcam.
 

post #12 of 24
Thread Starter 
@hanglee
What is compared to it at this price range should matter but highs and lows as reviewed are its weakest points as compared


@manzana
I prefer the audio gd for audiophile music listening as well
post #13 of 24

Strictly from an AMP/DAC headphone perspective:  How does this compare with the FiiO E17?

 

I found a like new Arcam rPAC for around $140 (which is a little more than what I paid for my e17) and am wondering if this would be considered an "upgrade".

 

Also, would I be able to connect my e17 to this and would it make any difference in the sound quality? For example can I use this as the primary DAC source for my laptop and use the e17 as the amp?

 

My main headphone at the moment is the Denon D2000 and primary earphone is the UE TF10 if that helps. 

post #14 of 24

I was considering pairing the rPac with a set of AKG Q701s. Does the rPac lack the power to drive these particular headphones? I'm not interested in listening at very high volumes, but I would like my music to be clearly audible.

post #15 of 24
Thread Starter 
Quote:
Originally Posted by AFRO insomniac View Post

Strictly from an AMP/DAC headphone perspective:  How does this compare with the FiiO E17?

 

I found a like new Arcam rPAC for around $140 (which is a little more than what I paid for my e17) and am wondering if this would be considered an "upgrade".

 

Also, would I be able to connect my e17 to this and would it make any difference in the sound quality? For example can I use this as the primary DAC source for my laptop and use the e17 as the amp?

 

My main headphone at the moment is the Denon D2000 and primary earphone is the UE TF10 if that helps. 

Sorry, I have too many threads I follow

 

The E17 from headphone out sounds better. No word on DAC out comparison between WM8740 and this DAC.

 

It depends on what you want to use it for, it is a specific product for specific uses. I mentioned what it is for in my review.

 

The kinda loose and somewhat boomy bass on the TF10 probably wouldn't work well with this. I never tried it as I got the TF10's JUST as I gave the unit to the next reviewr.

Quote:
Originally Posted by hugothedog View Post

I was considering pairing the rPac with a set of AKG Q701s. Does the rPac lack the power to drive these particular headphones? I'm not interested in listening at very high volumes, but I would like my music to be clearly audible.

IT depends. I have a different hearing volume preference than others. For example on the E17 I prefered E17 on 12dB gain at 45 volume when others using the same setup would prefer 6dB gain at 30 volume. If you like it quiet, the rPAC has enough power, if you want it loud. Then no.

 

The rPAC is a bit more of a fun unit. It depends on what you prefer but at the price, an ODAC and O2 combo may be better. I do not have the ODAC but I really liked the O2 with it.

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