This is a review and detailed measurements of the Teac S-300HR bookshelf coaxial speaker. It is on kind loan from a member. I can't find a price for it unfortunately.
I must say the finish on the S-300HR is one of the best if not the best I have seen on a speaker:
Even the back panel looks nice with that detailed Teac label:
I think these speakers went with their smaller electronics.
Measurements that you are about to see were 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 and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Using computational acoustics, far-field response is computed and that is what I present. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber.
I performed over 1000 measurement which resulted in error rate of about 1%. Clean high frequency response is responsible for ease of measurement in this regard.
Reference axis is approximately the center of the tweeter. Grill was not used.
Teac S-300HR Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker is and how it can be used in a room. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:
Gosh, this looks pretty poor. Bass output is low at just 81 to 82 dB. Response then gradually rises with multiple peaks indicating resonances. The only positive is that until you get to 8 kHz, resonances repeat in early window and sound power which means you should be able to EQ them down. Then again, you will have a very inefficient speaker when you do that.
Looking at the driver responses we see signs of the same resonances:
We can see them in the impedance curves as well:
I was surprised how much smoother early window reflection sum was:
This as such moderates our predicted in-room response:
So outside of bass, we really have a coupe of problem areas, one around 900 Hz to 1.5 kHz and anther peak around 4.5 kHz.
The beam width is variable due to woofer beaming (narrowing):
Looks a bit better in this view:
Benefit of coaxial design easily comes to light in the vertical directivity which is better than any traditional 2-way speaker:
I have a carpet on the floor and tall ceiling though so won't be doing me a lot of good.
Here is our center frequency 3-D horizontal Directivity Baloon:
We get a bit wiggly around 2 kHz but in grand scheme of things, it is decent and very nice by 3 kHz. Again, the coaxial design helps here.
Had a request in the last review to show three steps for distortion starting at 76 dBSPL. To whoever suggested that, I hate you I can't figure out a good way to show it without it taking up so much space!
Here is the relative distortion:
Clearly our little woofer is getting upset but the tweeter is sailing along.
Teac S-300HR Listening Tests
First impression wasn't bad. There was some of that "showroom sound" with heightened detail and some brightness. I brought out the EQ tools and tried to use the on-axis response to correct the resonances. While I got rid of the brightness, subjectively I still did not like the sound as it had gotten too dull. As I was writing the review I realized why: I should have used the predicted in-room response and corrected less. 90% of the time I find on-axis correction works best but this the 10% that works better with PIR.
Even with that EQ though, the main problem here is lack of bass. It is very muted so lets the rest of the spectrum stand out too much. I have a minimum standard that even a bookshelf speaker should provide satisfying response without the need for a sub. This speaker doesn't get there.
I should note that the woofer is graceful in handling volume, likely because it is not working too hard.
FYI the entire cabinet resonates with every bit of music. I am used to feeling something with bass notes and such in speakers. But here, the cabinet is acting like a musical instrument, vibrating consistently and all the time. Up close I thought I heard it contribute a "zingy" overtone to the speaker. Yes, that is a technical term!
Conclusions
The Teac S-300HR is gorgeously built. Alas, that doesn't extend to the objective performance. On-axis response is a mess with many resonances. Coaxial nature brings some value but I am not sure they are important things. Subjectively without sufficient bass, you are just going to be frustrated with the sound even if you EQ it as there is not enough headroom here to push the speaker.
Overall, I can't recommend the Teac S-300HR but do appreciate some aspects of it.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
I must say the finish on the S-300HR is one of the best if not the best I have seen on a speaker:
Even the back panel looks nice with that detailed Teac label:
I think these speakers went with their smaller electronics.
Measurements that you are about to see were 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 and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Using computational acoustics, far-field response is computed and that is what I present. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber.
I performed over 1000 measurement which resulted in error rate of about 1%. Clean high frequency response is responsible for ease of measurement in this regard.
Reference axis is approximately the center of the tweeter. Grill was not used.
Teac S-300HR Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker is and how it can be used in a room. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:
Gosh, this looks pretty poor. Bass output is low at just 81 to 82 dB. Response then gradually rises with multiple peaks indicating resonances. The only positive is that until you get to 8 kHz, resonances repeat in early window and sound power which means you should be able to EQ them down. Then again, you will have a very inefficient speaker when you do that.
Looking at the driver responses we see signs of the same resonances:
We can see them in the impedance curves as well:
I was surprised how much smoother early window reflection sum was:
This as such moderates our predicted in-room response:
So outside of bass, we really have a coupe of problem areas, one around 900 Hz to 1.5 kHz and anther peak around 4.5 kHz.
The beam width is variable due to woofer beaming (narrowing):
Looks a bit better in this view:
Benefit of coaxial design easily comes to light in the vertical directivity which is better than any traditional 2-way speaker:
I have a carpet on the floor and tall ceiling though so won't be doing me a lot of good.
Here is our center frequency 3-D horizontal Directivity Baloon:
We get a bit wiggly around 2 kHz but in grand scheme of things, it is decent and very nice by 3 kHz. Again, the coaxial design helps here.
Had a request in the last review to show three steps for distortion starting at 76 dBSPL. To whoever suggested that, I hate you I can't figure out a good way to show it without it taking up so much space!
Here is the relative distortion:
Clearly our little woofer is getting upset but the tweeter is sailing along.
Teac S-300HR Listening Tests
First impression wasn't bad. There was some of that "showroom sound" with heightened detail and some brightness. I brought out the EQ tools and tried to use the on-axis response to correct the resonances. While I got rid of the brightness, subjectively I still did not like the sound as it had gotten too dull. As I was writing the review I realized why: I should have used the predicted in-room response and corrected less. 90% of the time I find on-axis correction works best but this the 10% that works better with PIR.
Even with that EQ though, the main problem here is lack of bass. It is very muted so lets the rest of the spectrum stand out too much. I have a minimum standard that even a bookshelf speaker should provide satisfying response without the need for a sub. This speaker doesn't get there.
I should note that the woofer is graceful in handling volume, likely because it is not working too hard.
FYI the entire cabinet resonates with every bit of music. I am used to feeling something with bass notes and such in speakers. But here, the cabinet is acting like a musical instrument, vibrating consistently and all the time. Up close I thought I heard it contribute a "zingy" overtone to the speaker. Yes, that is a technical term!
Conclusions
The Teac S-300HR is gorgeously built. Alas, that doesn't extend to the objective performance. On-axis response is a mess with many resonances. Coaxial nature brings some value but I am not sure they are important things. Subjectively without sufficient bass, you are just going to be frustrated with the sound even if you EQ it as there is not enough headroom here to push the speaker.
Overall, I can't recommend the Teac S-300HR but do appreciate some aspects of it.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/