Plum Audio Dab+ Radio Tuner

[betty boop]

well I ordered one of these little devices

http://www.msml.com.au/msml/Plum_Audio.html

and it literally turned up over night which was a nice suprise. cost is $175 plus postage which is another $14, they let you pick up from their door if want to save on that.

anyways arrived safely here, comes in a neat box

http://www.dtvforum.info/index.php?act=att...ost&id=9486

and this is the unit unpacked and hooked up

http://www.dtvforum.info/index.php?act=att...ost&id=9487

which took all of a few minutes, the unit is very much plug and play, hook it up power it up and straight away it does a scan to find all stations and can then swap between the stations to listen

this is a shot of the remote, whcih is pretty much essential as unit itself has no buttons

http://www.dtvforum.info/index.php?act=att...ost&id=9489

this is how I have it hooked up

http://www.dtvforum.info/index.php?act=att...ost&id=9488

basically comes supplied with a wire antenna, which I didnt even bother unwinding, I have line of sight of the radio towers and this works fine as it is. it does have a f type connection so if wish could hook upto an external antenna or a telescopic antenna as you wish. Power is supplied with a plug pack, and audio out is via 2ch analog to my bedroom hifi system.

a shot here of the unit in my system

http://www.dtvforum.info/index.php?act=att...ost&id=9490

and system itself

http://www.dtvforum.info/index.php?act=att...ost&id=9491

the plum audio dab+ tuner is feeding a nad masterseries m3 2 channel pure analog stereo integrated, and speakers used are the pmc DB1i stand mount speakers.

Some early impressions of the plum audio dab+ tuner. It is a great little thing. pretty well put together, a bit plasticky but cost is pretty affordable. The unit in front profile is pretty contemporary in styling, but rearwards it does protrude with its back panel for connections, but I think this is intentional of the design to give the unit stability and means can hook up to some hefty interconnects without the thing tipping over...or being unbalanced in use.

In sound it is clean and clear, not the sharpest of treble, it is more a smooth airy sounding unit. But with depth of sound and good width of sound stage. Haven't done any comparisons with other source or other tuners but so far very happy with its sound. I have owned 3 other portable dab+ tuners in the pure highway, iriver b20 and b30 and so far this one suits this application to the tee.

In use it is suprisingly easy to use, just a matter of flicking between stations on the remote. an info button changes what you see on the display showing signal strength or track and artist info etc. When switched on the blue display cant be turned off or the blue led, which some might find annoying - there is a solution - tape over them, canbe done discretely !. But not really a bother for me. The LED goes from blue to red when the unit is turned off. I might get a little silver paper circle and stick that on top of the led as it really serves no purpose. when the unit is on you can see the display, when unit is off you dont see the display so dont really need an led as well ! but that is perhaps my only whinge at this stage !

The remote unit itself is fairly basic but theres not that many things you would need to do with a unit such as this and likely I will program in the basic functions of this unit into my harmony and pack away the remote.

Ideally this unit is pitched at someone with a 2ch setup or an av setup and wanting to add 2ch dab+ tuner. and it suits this application to a tee I think. price wise its miles away from the standalone hifi tuners so makes for very cheap buying. And perfect for someone looking for a dab+ tuner and not sure whether they want to spend a fortune on something at this stage. Size wise it is perfect for me as well as didnt want a full size component for my bedroom setup. and given size and shape I wouldnt want it any bigger as just fits in under my wall mounted lcd panel we have there. I'd say as a unit could also be discretly tucked away if dont necessarily want it on show.

Perhaps its not in the league of those I dont know, I'll compare it to my cambridge 650t dab+ tuner when get a chance that resides in my main hifi system.

Anyways will post a bit more in sonic comparisons when get a chance and also any further impressions of it in use

ps the remote does have a button for FM but not something played with as yet.

[MLXXX]

Thanks Al, for this review.

I suspect that generally speaking the quality of the sound will be very similar as between different DAB+ tuners, if not indistinguishable, though I recall that one DAB+ radio has its frequency response tailored to its in-built speaker.

Will be interested to see your report on comparing with the sound from your cambridge 650t.

Edited July 9, 2010 by MLXXX

[betty boop]

Thanks Al, for this review.

I suspect that generally speaking the quality of the sound will be very similar as between different DAB+ tuners, if not indistinguishable, though I recall that one DAB+ radio has its frequency response tailored to its in-built speaker.

Will be interested to see your report on comparing with the sound from your cambridge 650t.

thanks, but sorry that has not been my experience to date, I have certainly found differences between the 4 different dab+ units I have owned so far. But will certainly keep an open mind in comparing between the plum audio unit and my cambridge 650t

[MLXXX]

I guess my comment was made in the context that there are some major impacts on sound quality arising from the pre-processing that broadcasters use to give punch to their broadcasts (affecting the frequency response curve), and the fact that the processed sound has to run the gauntlet of HE-AAC compression, which is often around 64kbps. [The chip implementing the decompression algorithm in a DAB+ radio ought to deliver a decoded audio "as is", "warts and all", and operate in accordance with the defined algorithm.]

I have heard slight differences between a Pure Highway, a Roberts ecologic 4, and a Dabby USB. At some stage over the next few months I might make a simultaneous recording of all three and upload them for others to hear and compare. However I find the differences quite minor in comparison with the impact of HE-AAC compression. You'll recall my oft repeated complaint of lack of satisfaction with ABC classic FM at its nominal 80kbps. This morning I've been listening to Nova 1069 at its nominal 128kbps. It's quite something! Even though much of the music is not my cup of tea.

But will certainly keep an open mind in comparing between the plum audio unit and my cambridge 650t

As I say, I'll be quite interested in what you find.

[betty boop]

I guess my comment was made in the context that there are some major impacts on sound quality arising from the pre-processing that broadcasters use to give punch to their broadcasts (affecting the frequency response curve), and the fact that the processed sound has to run the gauntlet of HE-AAC compression, which is often around 64kbps. [The chip implementing the decompression algorithm in a DAB+ radio ought to deliver a decoded audio "as is", "warts and all", and operate in accordance with the defined algorithm.]

I have heard slight differences between a Pure Highway, a Roberts ecologic 4, and a Dabby USB. At some stage over the next few months I might make a simultaneous recording of all three and upload them for others to hear and compare. However I find the differences quite minor in comparison with the impact of HE-AAC compression. You'll recall my oft repeated complaint of lack of satisfaction with ABC classic FM at its nominal 80kbps. This morning I've been listening to Nova 1069 at its nominal 128kbps. It's quite something! Even though much of the music is not my cup of tea.

As I say, I'll be quite interested in what you find.

mlxx this thread of mine will not be a discussion of broadcast related matters I'll leave that to the myriad of other threads on the topic. It will simply be a comparison of this device vs my established benchmark in the cambridge 650t and at all times I will maintain the same broadcast material fed to the devices to keep that as a constant.

[MLXXX]

Good.

[betty boop]

Some listening comparisons :

I took the unit downstairs to my mains system, this is a combined 2ch and ht system, but am only testing this via the 2ch pure analog side in comparison to the cambridge 650t DAB+ tuner I have their.

a shot here showing the plum audio unit in my main system, can see the cambridge 650t located just below my turntable.

http://www.dtvforum.info/index.php?act=att...ost&id=9505

Some information here on the cambridge 650t is anyone is curious

http://www.cambridgeaudio.com/summary.php?PID=443

the 650t retails at $699 locally and something have owned for little while now since its release.

The system for comparison comprises off

musical fidelity a5cr pre amp

musical fidelity a5cr power amp

feeding my

Focal utopia diva main speakers that I have as front stage:

http://www.dtvforum.info/index.php?act=att...ost&id=8564

cables utilised are vdh and the same brand make and model vdh d102III hybrid was utilised for hooking up both items to my pre amp. The cambridge utilises a telescopic whip antenna, though I do not have it extended due to the excellent line of sight reception I have. The plum audio unit I am utilising the supplied whip cable antenna and do not have that extended either. Both units are showing excellent reception.

I utilised koffee dab+ broadcast to do my comparisons as quite happy with the audio quality of that station and familiar with the music it plays.

Also used an spl meter to check sound level from both units and found a slightly lower volume level from the plum unit so used a slightly louder volume setting to ensure I was comparing them at the same volume level.

My comparisons included listening through about a minute of a song on one of the devices before swapping to the next. I also included some back to back switching.

Immediate impression when even adjusting for volume level was the plum audio unit sound was weak in comparison to that from the cambridge 650t. The 650t is richer in every way vs the plum audio more flat sounding in comparison. Listening in a bit more depth, a couple of standouts the soundstage of the 650t is quite a bit more voluminous spreading out past the speakers vs when switching to the plum audio unit it seems to collapse to between the speakers and a lot more constrained. Listening a bit more closer it also appears the plum audio unit really misses the emphasis on transients vs the cambridge which seems to make them a lot more clear hence the feeling of the cambridge sounding a lot richer. The detail on an icehouse track for instance of the key board riff almost lost on the plum audio but quite distinct on the cambridge.

To be honest I am quite taken aback at the difference in sound quality. I boosted a bit of volume while listening to the plum audio unit but that didnt seem to make up for things. The very interesting thing though is that both units are certainly not miles away in sound charecter between them. As in one has an overblown bass or one has a warm sound vs more stringent sound of the other or anything. They are similar in sound to each other in that if listening to eithers sound in isolation I doubt anyone would be able to say that sounds like the plum unit or that the 650t. its just in comparison that the richer sound the cambridge has that is so blatantly obvious. I am though a bit of a fussy bugger when comes to audio with some pretty high standards so something to keep in mind ...

Some conclusions for me,

in isolation with the listening have done with it in my bedroom system the plum unit is pretty decent really, a good step up from the other portable units I've owned. And I think quite suitable for my bedroom system there where it will be mainly for back ground music and providing a music source upstairs when needed. I like its simplicity, its compact nature, its excellent reception with the antenna supplied - something I struggled and was a bit hit and miss with in the other portable units used. Also the nice big display of it is excellent too a lot more legible than the display of the cambridge.

The cambridge is in another league there is no question, but then there is a huge disparity in price between the units. You can buy 4 plum audio units for the price of the cambridge!. So I guess comes down to you do get what you pay for. The cambridge is a substantial unit too with I know a very decent torroidal power supply vs the plug pack of the plum unit, plus I know the cambridge also has a very decent wolfson dac configuration plus decent analog stage along the lines of their cd players. All likely miles apart from probably a pretty basic dac and analog stage of the plum considering the dollars it goes for and size limitations of the unit.

Look for the money I would still recommend the plum at only $175 its still less than what I paid for any of the dab+ portable units I've owned and more suited to applications where hooking upto a hifi or ht system. And what you get with the plum is pretty decent really for the money, as a dab+ tuner sitting somwhere between the portable units and more expensive standalone units like the cambridge 650t. And probably a good choice if you dont necessarily want to get a full size component tuner either due to cost or other limitations. Just dont compare it to something like the cambridge !

[laurie]

Thanks Al for the heads up may go direct to pickup one next week I'm going to modify it to work in the car as I have already built a DC-DC converter anyone here that may want to try it in the car this device will do the trick http://www.jaycar.com.au/productView.asp?I...mp;SUBCATID=665

cheers laurie

[betty boop]

Thanks Al for the heads up may go direct to pickup one next week I'm going to modify it to work in the car as I have already built a DC-DC converter anyone here that may want to try it in the car this device will do the trick http://www.jaycar.com.au/productView.asp?I...mp;SUBCATID=665

cheers laurie

Go for it laurie !

It should panel mount pretty easily or off a couple of brackets on the back. There's plenty of screw mounts you could pick up off.

The real beauty with this item is it has a proper f type antenna connection on it, so can hook unto any variety of commercial antennas available from the 15 dollar conventional extendable flex, or other boom antennas or just with the supplied wire antenna. Could even try teeing off your fm antenna of the car !

Look forward to hearing how you find it. It should be just fine in a car environment. Otherwise can be used setup indoors. Looking forward to your thoughts on the device

[MLXXX]

To be honest I am quite taken aback at the difference in sound quality. I boosted a bit of volume while listening to the plum audio unit but that didnt seem to make up for things. The very interesting thing though is that both units are certainly not miles away in sound charecter between them. As in one has an overblown bass or one has a warm sound vs more stringent sound of the other or anything. They are similar in sound to each other in that if listening to eithers sound in isolation I doubt anyone would be able to say that sounds like the plum unit or that the 650t. its just in comparison that the richer sound the cambridge has that is so blatantly obvious.

Thanks Al, for this.

I have heard distinct differences between FM radios. It seems we have to contend with marked differences between DAB+ tuners, too.

I think this highlights a problem with specifications for DAB+ radios. With a medium priced FM tuner you can see the manufacturer's specifications for THD, IMD, frequency response, stereo separation, quieting sensitivity, and signal to noise ratio. Hi-fi magazine reviewers will do their own objective measurements, as well as provide their subjective impressions. The cheaper the FM radio, the more abbreviated the specs may be.

How does this translate to DAB+ radios? We seem to be buying most of them "blind". No published specifications. And review magazines that possess no test equipment for DAB+ at this point in time.

I see the Cambridge 650T at least has some published specs for its DAB performance: Frequency response 20Hz - 20KHz ±0.3dB, and a very low figure for distortion, "<0.005%, @1kHz 2vrms o/p". Presumably this is for single test tones encoded with MP2 at a high bitrate.

I suggest that what a buyer of a DAB+ radio needs to know is how accurate the AAC+ decompression algorithm is at different bitrates. Is it bit perfect? I assume good designs are.

Edited July 10, 2010 by MLXXX

[betty boop]

a good point mlxx, the cambridge does have listed specifications, for FM, AM and DAB+ capability :

http://www.cambridgeaudio.com/specificatio...=Specifications

Azur 650T DAB+ / FM / AM RDS tuner

D/A Converters: Wolfson WM8740 24-Bit/192kHz capable

Frequency Range: FM (87.5 – 108MHz) Europe

FM (88 – 108MHz) US

AM (531 – 1620kHz) Europe

AM (530 – 1720kHz) US

DAB Band 3 (175MHz – 240MHz)

DAB L Band (1453MHz – 1491MHz

Aerial Inputs: 50 ohm F-Type (DAB)

75 ohm (FM)

Loop Antenna (AM)

Sensitivity: -25dBm typical

Signal to Noise: 105dB typical (DAB)

60dB typical (FM)

47dB typical (AM)

DAB Codec types supported: DAB (MP2) / DAB+ (AAC+)

Frequency Response: 20Hz – 20kHz ±0.3dB (NCT at Flat, DAB)

20Hz – 18kHz ±1dB (NCT at Flat, FM)

Distortion: <0.005%, @1kHz 2vrms o/p (DAB)

<0.3%, @ 1kHz, 50kHz deviation (FM)

<0.9%, @1kHz (AM)

S/P DIF output sample rate: 48kHz

Input Voltage: 220 – 230V AC ~ 50/60Hz (Europe)

115V AC ~ 50/60Hz (US)

Stereo Separation: @ 1kHz >50dB (FM)

Max. Power Consumption: 15W

Standby Power Consumption: <1W

Dimensions (H x W x D): 70 x 430 x 305mm (2.75 x 16.9 x 12.2’’)

Weight (unboxed): 4.8kg (10.6lbs)

Weight (boxed): 4.10kg (9lbs)

below are only specs I have been able to find on the plum audio unit, that are in the instruction manual

Specifications

Frequency range

DAB BAND III 174.928 - 239.200MHz

Frequency rage for quick scan is:

7A 188.928MHz to 13B 232.496MHz

Frequency range for full scan is:

5A 174.928MHz to 13F 239.200MHz

FM 87.5-108MHz

Audio output level

650mV (RMS)

Power supply

DC 9V 550mA

Power consumption

5W

Operating TEMP

0 to 50 deg C

make of that what you will...

[laurie]

Forget specs of devices if the stations bitrate are around 64Kb/s the only reason why I'm getting the Plum!

cheers laurie

[laurie]

Al

Are you sure the power consumption for the Plum is 5W because you wrote the Power Supply is 9v@500mA 5W=5000mA! maybe it should be .5W

cheers laurie

[betty boop]

Al

Are you sure the power consumption for the Plum is 5W because you wrote the Power Supply is 9v@500mA 5W=5000mA! maybe it should be .5W

cheers laurie

Hi Laurie, just posted what it says in the manual.

P=V x I

So plug pack rated at 9v and 550mA or 0.55A would be able to provide 9 x 0.55 = 4.95 W

And yeah it says power consumption of the unit is 5 W.

[laurie]

Hi Laurie, just posted what it says in the manual.

P=V x I

So plug pack rated at 9v and 550mA or 0.55A would be able to provide 9 x 0.55 = 4.95 W

And yeah it says power consumption of the unit is 5 W.

Thanks Al I'm having another senior moment gees 5w = 5000mA :blush: the reason I asked Al I thought a 9v battery will work in the car as a temp power supply

cheers laurie

[betty boop]

Thanks Al I'm having another senior moment gees 5w = 5000mA :blush: the reason I asked Al I thought a 9v battery will work in the car as a temp power supply

cheers laurie

Ah ok Laurie, there are 9v batteries and 9 v batteries !

Ps perhaps a phone charger that runs off the cigarette lighter imagine theres some 9v types with sufficient wattage

[laurie]

Ah ok Laurie, there are 9v batteries and 9 v batteries !

Ps perhaps a phone charger that runs off the cigarette lighter imagine theres some 9v types with sufficient wattage

I think most phone chargers are 3.7v @125Ma

cheers laurie

[laurie]

Picked mine up today very happy so far thanks again Al for the heads up

cheers laurie

[betty boop]

Picked mine up today very happy so far thanks again Al for the heads up

cheers laurie

Good stuff Laurie glad so far to your satisfaction. Do post back how you find it and how using it.

Definitely cost effe tie little device, filling the gap in the market place for people looking for a dab+ and fm tuner for their hifi av systems without breaking the bank !

[laurie]

Good stuff Laurie glad so far to your satisfaction. Do post back how you find it and how using it.

Definitely cost effe tie little device, filling the gap in the market place for people looking for a dab+ and fm tuner for their hifi av systems without breaking the bank !

I'm surprised how many expensive units don't supply line out sockets just headphone sockets given up on car install was told by owner he tried it but the reception varied as you drove down hills and between buildings unless you can tap into the radio aerial I have no inclination to pull the dash apart

cheers laurie

[betty boop]

I'm surprised how many expensive units don't supply line out sockets just headphone sockets given up on car install was told by owner he tried it but the reception varied as you drove down hills and between buildings unless you can tap into the radio aerial I have no inclination to pull the dash apart

cheers laurie

Yeah Laurie, I su spect those with headphone socket only really only ever designed to work that way and more for either desktop or portable use. This is certainly the first little unit have come across with line out sockets and a proper antenna f type connector.

Not surprised re the comment incar. I did have the pure highway and yeah was ok around my way where have line of sight of the towers but head inner city and soon even just go under a railway over pass and signal would drop out. Let alone in the city itself with all the building around. This was with even the pure supplied antenna. Using the headphone lead as antenna was even more hopeless.

Yeah they got a bit of work to do for incar in regards dab+. And probably till there's properly factory fitted dab+ radios in car it's probably not really ever going to be a reality.

[betty boop]

a couple of pics of the innards of the plum audio dab+ tuner here

http://www.dtvforum.info/index.php?act=att...ost&id=9691

http://www.dtvforum.info/index.php?act=att...ost&id=9692

can see its a pretty basic unit in design and implementation. can compare it with the cambridge audio 650t tuner have posted some pics of here

http://www.dtvforum.info/index.php?s=&...t&p=1588457

interestingly both use the same brand Gyro dab+ tuners, the plum uses a Gyro 1128 vs the 1128B of the cambridge, different customer numbers too so not sure the specific differences, but very clear the difference in analog and power supply implementation between the two units. with the cambridge being a lot more extensive in that area, not clear the dac utilised by the plum audio unit either.

either way for your money for the relative pittance the plum goes for its still fantastic value as a standalone tuner, keeping in mind the cambridge though a better sounding unit does cost many multiples more ...

[myrantz]

either way for your money for the relative pittance the plum goes for its still fantastic value as a standalone tuner, keeping in mind the cambridge though a better sounding unit does cost many multiples more ...

Are you thinking what I'm thinking? Don't even know where to start .. The board of the Cambridge is really really nice and clean though.

[betty boop]

Are you thinking what I'm thinking? Don't even know where to start .. The board of the Cambridge is really really nice and clean though.

haha I know what your thinking ! no my curiosity ends at taking a peak ! wont be taking any solder to it

yeah the cambrdige is beautifully made actually even the casing etc really well done. theyve definitely put some effort in the design of the thing

[Juffa]

Sorry to bring back this thread from the dead, but is still possible to buy one of these units.  Google has brought up the msml site, and the associated thirstforlife site....which still indicates you can buy them, but no actual way of buying it.  Have sent them an email, but thought I would also ask here. 

There is the cord and ezy-dab, but I would love coaxial or optical output, RCA output also good, but not really interested in a 3.5mm out put.

 

TIA