Articles, Reviews and Measurements of Audio Products
Tripp Lite IS250 Review (Isolation Transformer)
This is a review and detailed measurements of the Tripp Lite IS250 Isolation Transformer in the context of audio performance. I purchased it for US $140 with kind donation from a member.
The case is utilitarian but is not meant to be something you look at. Despite the low power rating of 250 Volt-Amp, the little box is quite heavy courtesy of the transformer inside. Back panel provides two outlets which is appreciated:
Notice the UL hologram/safety certification which is quite often lacking in audio tweak products.
Despite the name, please note that the safety earth ground is NOT isolated. Let me repeat: the safety ground pin in your outlet goes right through the device and comes out the same pin in the rear outlets. This is required for...
The case is utilitarian but is not meant to be something you look at. Despite the low power rating of 250 Volt-Amp, the little box is quite heavy courtesy of the transformer inside. Back panel provides two outlets which is appreciated:
Notice the UL hologram/safety certification which is quite often lacking in audio tweak products.
Despite the name, please note that the safety earth ground is NOT isolated. Let me repeat: the safety ground pin in your outlet goes right through the device and comes out the same pin in the rear outlets. This is required for...
Moondrop Blessing 2 Review (IEM)
This is a review and detailed measurements of the Moondrop Blessing 2 IEM. It was sent to me by Shenzhenaudio and costs US $320.
Blessing 2 feels substantial in hand without being overly large. The tips included are silicone and rather thin. This made it harder to mount on my headphone fixture but worked very well for my ears.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone/IEM measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I...
Blessing 2 feels substantial in hand without being overly large. The tips included are silicone and rather thin. This made it harder to mount on my headphone fixture but worked very well for my ears.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone/IEM measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I...
JBL SCL-7 Review (In-wall Speaker)
This is a review and detailed measurements of the JBL SCL-7 in-wall "custom" home theater speakers. It was purchased new by a member and kindly sent to me for testing. It costs US $1,100 each.
It is an interesting design with two mid-woofers and asymmetrical waveguide/horn. There is a near/far boundary setting. I tested it in far mode.
Measurements were performed using special mode of Klippel Near-Field Scanner which ignores everything outside of a radius in front of the speaker. As such it simulates speaker being mounted on infinitely large wall. Edge diffractions are also removed as are reflections.
Note: our company, Madrona Digital, is a dealer for Harman products including JBL line. While there is little subjective opinion in this write-up, feel free to read what level of bias you like.
JBL SCL-7 Measurements
As usual we start with our frequency response...
It is an interesting design with two mid-woofers and asymmetrical waveguide/horn. There is a near/far boundary setting. I tested it in far mode.
Measurements were performed using special mode of Klippel Near-Field Scanner which ignores everything outside of a radius in front of the speaker. As such it simulates speaker being mounted on infinitely large wall. Edge diffractions are also removed as are reflections.
Note: our company, Madrona Digital, is a dealer for Harman products including JBL line. While there is little subjective opinion in this write-up, feel free to read what level of bias you like.
JBL SCL-7 Measurements
As usual we start with our frequency response...
FiiO FD5 Review (IEM)
This is a review and detailed measurements of the FiiO FD5 IEM. It is on kind loan from a member and costs US $299.
The FD5 is very elegant looking and feeling. It is solid weight wise yet has those fine features. It is not too big so fit my ear easily.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass...
The FD5 is very elegant looking and feeling. It is solid weight wise yet has those fine features. It is not too big so fit my ear easily.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass...
64 Audio U12t Review (IEM)
This is a review and detailed measurements of the 64 Audio U12t IEM. It is on kind loan from a member and costs US $1,999.
Typical of these IEMs, the U12t is a chunky unit. While comfort was fine, it made it challenging at first to measure. Included cord was a bit too short for my taste but I think this is typical of IEMs. And alternate set of "silver" pipes come with the unit. I did not test that and stuck with the gray one you see in the picture.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I...
Typical of these IEMs, the U12t is a chunky unit. While comfort was fine, it made it challenging at first to measure. Included cord was a bit too short for my taste but I think this is typical of IEMs. And alternate set of "silver" pipes come with the unit. I did not test that and stuck with the gray one you see in the picture.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I...
Audio-Technica ATH-R70x Review (Headphone)
This is a review and detailed measurements of the Audio-Technica ATH-R70x open-back headphone. It was kindly sent to me by a member and costs US $349.
As you see the design is unusual with those support paddles. Even though the headphone is feather-light at just 205 grams, I found them uncomfortable to wear. The left cup was not quite large enough and bothered the edges of my ear. And the paddle above it felt like it was digging a hole in my head! Most headphones fit me well so this is one of the infrequent exceptions.
The connection to the headphones are locking 2.5mm connectors with long and thin cable which worked fine.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other...
As you see the design is unusual with those support paddles. Even though the headphone is feather-light at just 205 grams, I found them uncomfortable to wear. The left cup was not quite large enough and bothered the edges of my ear. And the paddle above it felt like it was digging a hole in my head! Most headphones fit me well so this is one of the infrequent exceptions.
The connection to the headphones are locking 2.5mm connectors with long and thin cable which worked fine.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other...
Sony Tapecorder 101 Review (Vintage Reel to Reel)
This is a review and detailed measurements of the Sony Tapecorder Model 101 vintage Reel to Reel tape recorder. My brother found it for me at a Goodwill store. The 101 was released in 1959 and retailed for 29,800 Japanese Yen (today's conversion and adjusted for inflation: $2,377).
I must stay it looks absolutely cute! It has a lid that covers it all. With it on, it would fit right in inside any fashion store. You can get a sense of that with a side shot:
The thing weighs a ton by the way for its size. There is a fan on the back and cute little door which exposes the AC cord connection inside it.
I have been anxious to measure it but took me a long time to find a test tape. Eventually I found one that has an odd tone of 315 Hz.
EDIT: this was an April Fool's...
I must stay it looks absolutely cute! It has a lid that covers it all. With it on, it would fit right in inside any fashion store. You can get a sense of that with a side shot:
The thing weighs a ton by the way for its size. There is a fan on the back and cute little door which exposes the AC cord connection inside it.
I have been anxious to measure it but took me a long time to find a test tape. Eventually I found one that has an odd tone of 315 Hz.
EDIT: this was an April Fool's...
Vanatoo Transparent One Encore (Powered Speaker)
This is a review and detailed measurements of the Vanatoo Transparent One Encore powered/computer speaker. It was sent to me by the company and costs US $599 for a pair (in black and cherry).
This is small speaker but is quite heavy for its size and feels quite dense. All the electronics are in one speaker and four wires drive the slave indicating active (DSP) configuration. Back panel shows very rich connectivity (including remote control which is not shown):
You are not going to find features like digital input, sub out, etc. in any budget professional monitor but you have it here and then some. That passive radiator is a serious looking thing in person as well.
Measurements that you are about to see were performed using the...
This is small speaker but is quite heavy for its size and feels quite dense. All the electronics are in one speaker and four wires drive the slave indicating active (DSP) configuration. Back panel shows very rich connectivity (including remote control which is not shown):
You are not going to find features like digital input, sub out, etc. in any budget professional monitor but you have it here and then some. That passive radiator is a serious looking thing in person as well.
Measurements that you are about to see were performed using the...