Articles, Reviews and Measurements of Audio Products
KIMBER KABLE: Do High-end USB Cables Make A Difference?
This is a review and detailed measurements of the KIMBER KABLE B-BUS USB cable. It is on kind loan from a member. The B-BUS in 1 meter length costs US $60 from the company.
Complain all you want about high-end cables. Where they usually distinguish themselves is the fancy look of their cables. Well, Kimber must have been absent on the day that marketing lesson was taught as the B-BUS is an ugly purple and looks as plain as it possibly could:
Some lofty claims are made about the cable:
I sure hope so after paying 10 times as much for this cable. Then there is this endorsement from the founder of audiophilestyle online blog/forum, Chris Connaker:
You don't say Chris.... Let's find out if there are such interference that have been stopping the rest of us from hearing the "original recording."
USB Cable Audio Measurements
Let's start test this USB cable with one of...
Complain all you want about high-end cables. Where they usually distinguish themselves is the fancy look of their cables. Well, Kimber must have been absent on the day that marketing lesson was taught as the B-BUS is an ugly purple and looks as plain as it possibly could:
Some lofty claims are made about the cable:
I sure hope so after paying 10 times as much for this cable. Then there is this endorsement from the founder of audiophilestyle online blog/forum, Chris Connaker:
You don't say Chris.... Let's find out if there are such interference that have been stopping the rest of us from hearing the "original recording."
USB Cable Audio Measurements
Let's start test this USB cable with one of...
Analysis Plus Oval Digital XLR Cable Review
This is a review and detailed measurements of the Analysis Plus Oval XLR "Digital" cable. It is on kind loan from a member. I had a hard time finding information on this cable as it is not listed by Analysis Plus but there are sellers who do carry it. It costs US 190 for a one meter length of it. The description on those sites raves about 75 ohm matching impedance but AES digital audio is a 110 ohm standard, not 75 ohm. Maybe that refers to the RCA version.
The Analysis Plus Oval cable doesn't look too bad and is not overly stiff:
There is a patent number on the cable which I did not other to look up.
Digital Audio Cable Audio Measurements
I thought I start by using my Audio Precision APx555 in its digital analysis mode. Here, it is able to extract jitter from the digital stream and analyze it as if it is audio:
The signal being played is J-test which is at 12 kHz and has a 250 Hz square...
The Analysis Plus Oval cable doesn't look too bad and is not overly stiff:
There is a patent number on the cable which I did not other to look up.
Digital Audio Cable Audio Measurements
I thought I start by using my Audio Precision APx555 in its digital analysis mode. Here, it is able to extract jitter from the digital stream and analyze it as if it is audio:
The signal being played is J-test which is at 12 kHz and has a 250 Hz square...
Micca RB42 Bookshelf Speaker Review
This is a review and detailed measurements of the Micca RB42 bookshelf/desktop computer speaker. I purchased my sample from Amazon and it cost US $149 including Prime shipping. This speaker also seems to be the favorite of youtube bloggers, helped partly by generous seeding of such "reviewers."
The RB42 looks stunningly good for such a budget price if you stand a bit far:
Curved cabinet with excellent fit and finish that would be at home (if it were a larger cabinet) in a high-end audio shop.
Zoom in though and you see that budget pricing doesn't get you perfection:
I don't know what the two white dots are. They would not come off easily. The lousy gluing job of the dust cap encourages one to put them far from eyesight.
The back panel impresses again with nice binding posts:
If you didn't tell me in advance and I did not look...
The RB42 looks stunningly good for such a budget price if you stand a bit far:
Curved cabinet with excellent fit and finish that would be at home (if it were a larger cabinet) in a high-end audio shop.
Zoom in though and you see that budget pricing doesn't get you perfection:
I don't know what the two white dots are. They would not come off easily. The lousy gluing job of the dust cap encourages one to put them far from eyesight.
The back panel impresses again with nice binding posts:
If you didn't tell me in advance and I did not look...
Aimpire AD10: Fake Topping D10 DAC?
A member purchased what he thought was a Topping D10 DAC from Amazon as the seller. The unit that he received however had the brand "Aimpire" and model number AD10. He asked me if I could look to see if it performs the same or is a fake.
Looking on Amazon, one clearly sees the issue:
Yet the picture of what the device looks like the one that the member received:
This curious note on Amazon page makes the buy think this is a newer version:
Stacking the real Topping D10 on top of Aimpire AD10 shows the striking similarity:
In use however, the display of sample rate on AD10 fake is dim and not matching the PCM/DSD. The reverse is true on real Topping D10 where the sample rate is bright and clear and the PCM/DSD is merely in sharper front.
Plugging either DAC in gets identified as "D10" so clearly the identity of the USB...
Looking on Amazon, one clearly sees the issue:
Yet the picture of what the device looks like the one that the member received:
This curious note on Amazon page makes the buy think this is a newer version:
Stacking the real Topping D10 on top of Aimpire AD10 shows the striking similarity:
In use however, the display of sample rate on AD10 fake is dim and not matching the PCM/DSD. The reverse is true on real Topping D10 where the sample rate is bright and clear and the PCM/DSD is merely in sharper front.
Plugging either DAC in gets identified as "D10" so clearly the identity of the USB...
Headroom Balanced Desktop Ultra Amp Review
This is a review and detailed measurements of the Headroom Balanced Desktop Ultra Amplifier. It is on kind loan from a member. Better known as "BUDA," the unit came out in 2011 I think and cost US $1,189.
The BUDA reminds me of getting my first headroom amplifier circa 1999 (bought a portable and then a desktop unit with the latter being a disappointment). It is a chunky unit with outboard power supply:
You can use two headphones with 1/4 stereo jacks or one balanced headphone with dual male XLR connectors.
The back panel is what you expect:
The large, 40 watts external power supply gave me hope of lots of power into low impedance loads. Alas, measurements showed this hope was misplaced.
I used the XLR Input for all of my testing.
Headphone Amplifier Measurements
Here is our performance with 4 volts in using XLR, and 4 volts out using stereo 1/4 jack...
The BUDA reminds me of getting my first headroom amplifier circa 1999 (bought a portable and then a desktop unit with the latter being a disappointment). It is a chunky unit with outboard power supply:
You can use two headphones with 1/4 stereo jacks or one balanced headphone with dual male XLR connectors.
The back panel is what you expect:
The large, 40 watts external power supply gave me hope of lots of power into low impedance loads. Alas, measurements showed this hope was misplaced.
I used the XLR Input for all of my testing.
Headphone Amplifier Measurements
Here is our performance with 4 volts in using XLR, and 4 volts out using stereo 1/4 jack...
Selah Audio RC3R 3-way Speaker Review
This is a review and detailed measurements of the Selah Audio vintage RC3R 3-way speaker. It is on kind loan from a local member. From what I can tell, the Rc3R came out around 2003 and it cost full built for around US $1,300. Kits were available for half the price.
Please excuse the poor mobile phone picture as the unit is still on the measurement stand:
The cabinet seems quite solid and finish nice.
As you can tell, it is a 3-way design. Here are the specs for the drivers which I had a hell of a time to find:
Drivers
(1) Scan-Speak 18W8545
(1) Morel MDM-55
(1) ATD LeRibbon
I am only going to present the measurements as I have to rush to our audiophile society meeting where I can return this and other speakers to their owners.
Measurements of the Selah Audio vintage RC3R were performed using the Klippel Near-field Scanner (NFS)...
Please excuse the poor mobile phone picture as the unit is still on the measurement stand:
The cabinet seems quite solid and finish nice.
As you can tell, it is a 3-way design. Here are the specs for the drivers which I had a hell of a time to find:
Drivers
(1) Scan-Speak 18W8545
(1) Morel MDM-55
(1) ATD LeRibbon
I am only going to present the measurements as I have to rush to our audiophile society meeting where I can return this and other speakers to their owners.
Measurements of the Selah Audio vintage RC3R were performed using the Klippel Near-field Scanner (NFS)...
Emotiva Airmotiv 6s Powered Speaker Review
This is a review and detailed measurements of the Emotiva Airmotiv 6s. It is on kind loan from a member. The 6s is discontinued but I think it cost US $400 for a pair.
The 6s is a chunky and large monitor as these devices go:
I was surprised that there was no gain control available:
Input sensitivity even with XLR input was very high. I had to drive it with just 0.13 volts for the testing.
The 6S is quite heavy as well with a dense cabinet.
Measurements of the Emotiva 6s was performed using the Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics) to subtract room reflections. It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Both of these...
The 6s is a chunky and large monitor as these devices go:
I was surprised that there was no gain control available:
Input sensitivity even with XLR input was very high. I had to drive it with just 0.13 volts for the testing.
The 6S is quite heavy as well with a dense cabinet.
Measurements of the Emotiva 6s was performed using the Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics) to subtract room reflections. It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Both of these...
Denafrips ARES II USB R2R DAC Review
This is a review and measurements of the Denafrips ARES II USB DSD DAC based on R2R architecture. It is on kind loan from a member. I think it costs US $680 so not too high for a custom DAC.
The overall look of the ARES II is rather plain:
The LED indicators are quite tiny so standing top of it, I could not tell they were on.
There is a large toroidal transformer in there making the ARES II quite heavy. So at least on that front, you get the feeling that you are getting your money's worth.
The back panel has the usual connectors:
I was pleased to see balanced XLR outputs as this increases the cost substantial in R2R implementations. I used that for all of my testing.
R2R DAC Audio Measurements
As usual we start with our 1 kHz dashboard:
Oh, this is pretty good! THD+N is 10 times better than the specification and the highest distortion product...
The overall look of the ARES II is rather plain:
The LED indicators are quite tiny so standing top of it, I could not tell they were on.
There is a large toroidal transformer in there making the ARES II quite heavy. So at least on that front, you get the feeling that you are getting your money's worth.
The back panel has the usual connectors:
I was pleased to see balanced XLR outputs as this increases the cost substantial in R2R implementations. I used that for all of my testing.
R2R DAC Audio Measurements
As usual we start with our 1 kHz dashboard:
Oh, this is pretty good! THD+N is 10 times better than the specification and the highest distortion product...
KEF LS50 Bookshelf Speaker Review
This is a review and detailed measurements of the famous KEF LS50 speaker. It was kindly loaned to me by a local member. The LS50 costs US $1,500 but seems to be on sale for US $1,300 on Amazon and elsewhere.
The LS50 nails the look of the speaker with the bright color and shape of the concentric driver:
80% of the success of a speaker in this super crowded market is the industrial design and KEF nails that. The enclosure itself feels like it is solid all the way to its core!
Not much exciting on the back other than nice sized speaker terminals and a port that has benefited from good simulations:
My company became a KEF dealer for a short period of time when the LS50 had just come out. We set it up with a Revel sub optimized for the room with DSP and it sounded good in our little room. Since then I have heard it at shows but no opportunity for careful analysis of it.
Of course...
The LS50 nails the look of the speaker with the bright color and shape of the concentric driver:
80% of the success of a speaker in this super crowded market is the industrial design and KEF nails that. The enclosure itself feels like it is solid all the way to its core!
Not much exciting on the back other than nice sized speaker terminals and a port that has benefited from good simulations:
My company became a KEF dealer for a short period of time when the LS50 had just come out. We set it up with a Revel sub optimized for the room with DSP and it sounded good in our little room. Since then I have heard it at shows but no opportunity for careful analysis of it.
Of course...
Harbeth Monitor 30 Speaker Review
This is a review and detailed measurements of the Harbeth Monitor 30 25th anniversary speaker. It is on kind loan from a local member. This specific speaker came out around 2002 I think and cost US $3,200 around that time. Being patterned after the famous BBC LS 5/9 speakers, I imagine the design is still the same to this day. The latest model seems to go by 30.1 designation.
The Harbeth logo was in danger of coming off so the owner pulled it off. Here is what it looks like (I know, very bland):
It barely fit in my little photo booth so not very large. The grill is tricky to remove so I did not attempt to do so. I am told the recommendation is to use it with the grill so that is how I measured it.
The back panel shows ability for bi-wiring:
Love the bit about the speaker being in their log book. Well, its measurements are now in our log book as well.
Let's get into...
The Harbeth logo was in danger of coming off so the owner pulled it off. Here is what it looks like (I know, very bland):
It barely fit in my little photo booth so not very large. The grill is tricky to remove so I did not attempt to do so. I am told the recommendation is to use it with the grill so that is how I measured it.
The back panel shows ability for bi-wiring:
Love the bit about the speaker being in their log book. Well, its measurements are now in our log book as well.
Let's get into...