SUB THREE (Pair) - Ordered

[Schuesmp]

Last week, I placed an order for a pair of SUB THREE subwoofers and M5-HPB crossovers for use in one of my two-channel audio systems that features Audio Physic Cardeas loudspeakers and Balanced Audio Technology (“BAT”) vacuum tube amplification. The two SUB THREE’s will replace a single REL 212/SX subwoofer, which will be redeployed to an audio-video system with bass management and room correction incorporated in an Anthem processor. The Audio Physic Cardeas loudspeakers already dig deep into the low frequencies and deliver a flavor of sound and presentation I enjoy immensely, but I predict an uplift in overall system performance from partially relieving my BAT 75-watt vacuum tube power amplifier from supporting frequencies below 80 Hz - a big part of the SUB THREE’s value. I predict excellent results.

I also run a separate system using Vandersteen Quatro Wood CT loudspeakers, which are tremendous and established my appreciation for Vandersteen’s approach to optimizing in-room bass performance. I like to experiment with different loudspeaker and amplification configurations, so have gained substantial experience re-EQ’ing the bass sections of my Quatro Wood CT’s. What a powerful and effective feature!

Somewhat separately, I am SO GLAD to have a Vandersteen dealer back in Portland, Oregon. Stereotypes Audio took on Vandersteen not long ago, but have demonstrated commitment and knowledge. While visiting Stereotypes to place my order for the SUB THREE’s, I listened to several songs through the current version of the Model 2ce. So good!

[Schuesmp]

In case anyone is curious about the look and configuration of Audio Physic Cardeas loudspeakers:

[stratocaster]

Beautiful .. is the surface near the drivers glossy since the reflection is so clear…

[Schuesmp]

4 minutes ago, stratocaster said:

Beautiful .. is the surface near the drivers glossy since the reflection is so clear…

It is a treated glass material. I paused when I saw and read about this design approach, but Audio Physic is quite deliberate with its use of glass in its cabinets, and my listening experience cannot fault it.

Edited February 22, 2023 by Schuesmp

[GdnrBob]

You'll really hear a difference with the Sub 3's. REL is a good sub, but Vandy's integration is seamless.

Bob

[ctsooner]

Pretty speakers for sure. Thanks for sharing. Interesting about your take on Vandy approach. Thanks. 
 

those subs are special. I can’t wait to hear your thoughts. 

[Schuesmp]

On 2/23/2023 at 6:19 AM, GdnrBob said:

You'll really hear a difference with the Sub 3's. REL is a good sub, but Vandy's integration is seamless.

Bob

The REL has been an excellent subwoofer in the system. With its two 12-inch active drivers and two 12-inch passive radiators, it can move serious air with impressive speed and articulation. However, it is much more difficult to achieve an ideal low-frequency response and seamless blend with the main stereo loudspeakers, as compared to a Vandersteen subwoofer incorporating a high-pass filter and EQ - learned from years of use and enjoyment of my Quatro Wood CT.

[Schuesmp]

On 2/23/2023 at 7:32 AM, ctsooner said:

Pretty speakers for sure. Thanks for sharing. Interesting about your take on Vandy approach. Thanks. 
 

those subs are special. I can’t wait to hear your thoughts. 

Thanks. I should have the SUB THREE's in five or six weeks.

[Holmz]

2 hours ago, Schuesmp said:

The REL has been an excellent subwoofer in the system. With its two 12-inch active drivers and two 12-inch passive radiators, it can move serious air with impressive speed and articulation. However, it is much more difficult to achieve an ideal low-frequency response and seamless blend with the main stereo loudspeakers, as compared to a Vandersteen subwoofer incorporating a high-pass filter and EQ - learned from years of use and enjoyment of my Quatro Wood CT.

But what ‘order’ are the Audio Physic crossovers?
It gets difficult to mix-n-match, and the Vandy subs may only work a treat with the Vandy 1st order XO?
(Dunno… Maybe they work a treat elsewhere too…)

[Schuesmp]

21 minutes ago, Holmz said:

But what ‘order’ are the Audio Physic crossovers?
It gets difficult to mix-n-match, and the Vandy subs may only work a treat with the Vandy 1st order XO?
(Dunno… Maybe they work a treat elsewhere too…)

In my configuration, the Vandersteen SUB THREE system is augmenting bass up to only around 80-100 Hz, and the Audio Physic Cardeas loudspeakers have an efficiency rating that sits nicely within the range specified by Vandersteen for incorporating SUB THREE(s). The likelihood of the pair of SUB THREE, after proper EQ, not significantly improving the overall sound is remote in my view. If I’m wrong, my audio system using Quatro Wood CT’s would take on the SUB THREE’s, or I may consider adding them to another audio system using VLR CT’s. Plan B and Plan C are pretty sweet. I previously owned two Vandersteen 2Wq subwoofers, which I used with multiple non-Vandersteen loudspeakers, and they always delivered.

[Holmz]

I am pretty sure it will sound good @Schuesmp.

I tried to give a set of my HPFs to my ski buddy on loan, but he likely going a different route.
(On his Maggys)

[Schuesmp]

15 minutes ago, Holmz said:

I am pretty sure it will sound good @Schuesmp.

I tried to give a set of my HPFs to my ski buddy on loan, but he likely going a different route.
(On his Maggys)

Maybe someday, Richard Vandersteen will share how he developed his high-pass filters designed to operate between users’ (in some cases) very fancy interconnects and very fancy power amplifiers without noticeably robbing their character. I find his filters pretty darn transparent.

[Richard Vandersteen]

2 hours ago, Schuesmp said:

Maybe someday, Richard Vandersteen will share how he developed his high-pass filters designed to operate between users’ (in some cases) very fancy interconnects and very fancy power amplifiers without noticeably robbing their character. I find his filters pretty darn transparent.

We cheat!  Turns out when you put a first order low frequency transfer function on any system the sound improves dramatically especially transient response.  It also lowers the distortion of the main amplifier because the load on the power supply is reduced effectively as if the power supply has been significantly enlarged.  Now we know anytime something is added in the signal path the sound will take a step back, but the previously described improvements improve the sound more than the step backwards.  Like the drunk who falls back a step for every two steps he goes forward!  Ah, but he still moves a step forward in the process.  If you don't see the step backwards one only notices the progress.  As I said we cheat but you benefit!  RV

[Schuesmp]

54 minutes ago, Richard Vandersteen said:

We cheat!  Turns out when you put a first order low frequency transfer function on any system the sound improves dramatically especially transient response.  It also lowers the distortion of the main amplifier because the load on the power supply is reduced effectively as if the power supply has been significantly enlarged.  Now we know anytime something is added in the signal path the sound will take a step back, but the previously described improvements improve the sound more than the step backwards.  Like the drunk who falls back a step for every two steps he goes forward!  Ah, but he still moves a step forward in the process.  If you don't see the step backwards one only notices the progress.  As I said we cheat but you benefit!  RV

For the win!

[Schuesmp]

Hello, everyone. I took delivery of the pair of SUB THREE subwoofers and M5-HPB crossovers on April 7th. At the moment, I am running only one of the two subwoofers. I configured the M5-HPB crossovers using a digital voltmeter, Vandertones, and Vandersteen’s technique demonstrated by Richard in a YouTube video (very helpful). The M5-HPB crossovers connect to the inputs of my Balanced Audio Technology (“BAT”) VK-76SE vacuum tube stereo power amplifier. The main loudspeakers in play are Audio Physic Cardeas, which Audio Physic states have an impedance of 4 Ohm. The BAT VK-76SE power amplifier has 4-, 6-, and 8-Ohm output taps. I use the 4-Ohm output taps, which sound the best to my ears.

I am struggling to achieve sufficient output from the SUB THREE, which I suspect is user error. At each of multiple subwoofer placements in my room, with the SUB THREE’s sensitivity (level) dial set to nearly maximum, and after substantial effort to EQ using the subwoofer’s 11 bands, I cannot achieve a full, balanced sound. Even when using rather extreme EQ settings, the 60 Hz and below frequency bands are approximately 8 dB or more below the target.

Before I continue experimenting, I ask the group whether use of a vacuum tube power amplifier with one or more SUB THREE subwoofers and M5-HPB crossovers changes the setup and calibration approach described in the Operation Manual? I currently use in a separate audio system a pair of Vandersteen Quatro Wood CT loudspeakers, and I have owned in the past Vandersteen 2Wq subwoofers, so I have a sense of the magnitude and quality of bass output that I should expect from the SUB THREE.

I invite all suggestions, thoughts, and views. Thanks!

[Holmz]

1 hour ago, Schuesmp said:

I invite all suggestions, thoughts, and views. Thanks!

Well IME there are only 2 possibilities:

1. The amp has no umph at the lower freqs  
2. The speakers and teh sub are out of phase with each other.

Assuming you do not have a mic and do not have REW, then I would take readings with just the speakers at 20, 30, 40 -100 Hz.
And then turn on the sub and take readings at those same freqs.

If the sub is out of phase then you should find that you can twist the pots to make the readings go right to zero when the sub and the main speakers have identical output.

If that was the case, then I am not sure , but maybe it is possible to wire the main speakers, or the subs, out of phase.
I am not sure how we know about the amp not having the umph, but a transformer coupled and/or capacitor output can also be in place to save the amp from trying to put out DC.

 

If I was any good, I would be able to mathematically noodle it out… but a man has to know is limitations.

[Schuesmp]

11 minutes ago, Holmz said:

Well IME there are only 2 possibilities:

1. The amp has no umph at the lower freqs  
2. The speakers and teh sub are out of phase with each other.

Assuming you do not have a mic and do not have REW, then I would take readings with just the speakers at 20, 30, 40 -100 Hz.
And then turn on the sub and take readings at those same freqs.

If the sub is out of phase then you should find that you can twist the pots to make the readings go right to zero when the sub and the main speakers have identical output.

If that was the case, then I am not sure , but maybe it is possible to wire the main speakers, or the subs, out of phase.
I am not sure how we know about the amp not having the umph, but a transformer coupled and/or capacitor output can also be in place to save the amp from trying to put out DC.

 

If I was any good, I would be able to mathematically noodle it out… but a man has to know is limitations.

Holmz:

Thank you. You have given me ideas for experimenting further tomorrow; specifically, I intend to try (1) reversing the SUB THREE's polarity and (2) evaluating SPL meter results from playing Vandertones with and without the SUB THREE/M5-HPBs in the chain, focusing on 20-100 Hz. I do have a measurement microphone, but I use a program called AudioTools, instead of REW. This is perhaps subjective, but I view my BAT VK-76SE power amplifier as having plenty of oomph. Without augmentation using a subwoofer, the amplifier gets the Audio Physic Cardeas loudspeakers rocking. 

Thanks, again.  

[Holmz]

AudioTools should work like a champ.
I think it does sweeps too.

[Richard Vandersteen]

8 hours ago, Schuesmp said:

Holmz:

Thank you. You have given me ideas for experimenting further tomorrow; specifically, I intend to try (1) reversing the SUB THREE's polarity and (2) evaluating SPL meter results from playing Vandertones with and without the SUB THREE/M5-HPBs in the chain, focusing on 20-100 Hz. I do have a measurement microphone, but I use a program called AudioTools, instead of REW. This is perhaps subjective, but I view my BAT VK-76SE power amplifier as having plenty of oomph. Without augmentation using a subwoofer, the amplifier gets the Audio Physic Cardeas loudspeakers rocking. 

Thanks, again.  

Do not use the SUB THREE, 2W or 2Wq without the signal hi-passed!  The input opp amps may fail (non warrantee) because it was not designed for the 30 dB excess signal.  RV

[Richard Vandersteen]

10 hours ago, Schuesmp said:

Hello, everyone. I took delivery of the pair of SUB THREE subwoofers and M5-HPB crossovers on April 7th. At the moment, I am running only one of the two subwoofers. I configured the M5-HPB crossovers using a digital voltmeter, Vandertones, and Vandersteen’s technique demonstrated by Richard in a YouTube video (very helpful). The M5-HPB crossovers connect to the inputs of my Balanced Audio Technology (“BAT”) VK-76SE vacuum tube stereo power amplifier. The main loudspeakers in play are Audio Physic Cardeas, which Audio Physic states have an impedance of 4 Ohm. The BAT VK-76SE power amplifier has 4-, 6-, and 8-Ohm output taps. I use the 4-Ohm output taps, which sound the best to my ears.

I am struggling to achieve sufficient output from the SUB THREE, which I suspect is user error. At each of multiple subwoofer placements in my room, with the SUB THREE’s sensitivity (level) dial set to nearly maximum, and after substantial effort to EQ using the subwoofer’s 11 bands, I cannot achieve a full, balanced sound. Even when using rather extreme EQ settings, the 60 Hz and below frequency bands are approximately 8 dB or more below the target.

Before I continue experimenting, I ask the group whether use of a vacuum tube power amplifier with one or more SUB THREE subwoofers and M5-HPB crossovers changes the setup and calibration approach described in the Operation Manual? I currently use in a separate audio system a pair of Vandersteen Quatro Wood CT loudspeakers, and I have owned in the past Vandersteen 2Wq subwoofers, so I have a sense of the magnitude and quality of bass output that I should expect from the SUB THREE.

I invite all suggestions, thoughts, and views. Thanks!

What is the sensitivity of the Cardeas?  If you need more sensitivity, you can drive both inputs and get a 6 dB bump.  You do have the high pass at 80 Hz?  RV

[Schuesmp]

6 minutes ago, Richard Vandersteen said:

Do not use the SUB THREE, 2W or 2Wq without the signal hi-passed!  The input opp amps may fail (non warrantee) because it was not designed for the 30 dB excess signal.  RV

Richard: Thank you for chiming in. In my experiment, which perhaps I did not articulate clearly enough, the SUB THREE and M5-HPB would always be used together. The SPL meter readings would be taken (1) with the SUB THREE/M5-HPBs in the chain and (2) completely without (i.e., main loudspeakers only).

[Schuesmp]

3 minutes ago, Richard Vandersteen said:

What is the sensitivity of the Cardeas?  If you need more sensitivity, you can drive both inputs and get a 6 dB bump.  You do have the high pass at 80 Hz?  RV

The sensitivity of the Cardeas is 89 dB.

My use of the single SUB THREE, thus far, has involved running four speaker cables between the stereo power amplifier and the subwoofer (Right +/- and Left +/-), so I believe I am achieving the 6 dB bump.

I configured the high pass at 80 Hz using a digital voltmeter and Vandertones - 1.00 V at 1000 Hz, and around 0.725 V at 80 Hz.

[Richard Vandersteen]

1 hour ago, Schuesmp said:

The sensitivity of the Cardeas is 89 dB.

My use of the single SUB THREE, thus far, has involved running four speaker cables between the stereo power amplifier and the subwoofer (Right +/- and Left +/-), so I believe I am achieving the 6 dB bump.

I configured the high pass at 80 Hz using a digital voltmeter and Vandertones - 1.00 V at 1000 Hz, and around 0.725 V at 80 Hz.

 

1 hour ago, Schuesmp said:

The sensitivity of the Cardeas is 89 dB.

My use of the single SUB THREE, thus far, has involved running four speaker cables between the stereo power amplifier and the subwoofer (Right +/- and Left +/-), so I believe I am achieving the 6 dB bump.

I configured the high pass at 80 Hz using a digital voltmeter and Vandertones - 1.00 V at 1000 Hz, and around 0.725 V at 80 Hz.

When you are measuring your speakers only it won't take phase into account.  Only when combining them with a known phase correct second source will the sum of the two show how phase correct the speaker is.  I would try running the SUB THREE out of phase and see it you get better summing.  Remember most of the world thinks phase does not matter!  RV

[Schuesmp]

1 minute ago, Richard Vandersteen said:

 

When you are measuring your speakers only it won't take phase into account.  Only when combining them with a known phase correct second source will the sum of the two show how phase correct the speaker is.  I would try running the SUB THREE out of phase and see it you get better summing.  Remember most of the world thinks phase does not matter!  RV

Thank you, Richard. I will do what you suggest.

Phase matters, of course, which I learned the first time I attempted to record a kick drum using three microphones placed too close together.

[Schuesmp]

Running the SUB THREE out of phase (i.e., with polarity reversed) did the trick. After redoing the EQ, each of the 11 frequency bands is within 25% of target. More importantly, the SUB THREE is contributing to an overall full, balanced sound.

My sincere thanks to Holmz and Richard Vandersteen for the assistance.