My nostalgia and preference for large glass-face VU meters: DIY of 12-VU-Meter Array in multichannel multi-driver multi-way multi-amplifier stereo audio system
Edit: notation for specific search hit to this post: "Dualazmak DIY 12-VU-Meter Array" e.g. in YouTube clips.
Abbreviations in this post;
SW: sub-woofer, Yamaha YST-SW1000 (L & R)
WO: woofer, Yamaha NS-1000’s 30 cm JA-3058
SQ: squawker, Yamaha NS-1000’s 8.8 cm Beryllium dome JA-0801
TW: tweeter, Yamaha NS-1000’s 3 cm Beryllium dome JA-0513
ST: super-tweeter, Fostex metal horn T925A
Edit:
- Dancing video of my IEC 60268-17 compatible large glass-face DIY 12-VU-Meter Array
_____Part-1: with "High Frequency Linearity Check Track" of Sony Super audio Check CD: #750
_____Part-2: with typical "Full Orchestra Music"-1: #751
_____Part-3: with typical "Full Orchestra Music"-2: #752
_____Part-4: with typical "Jazz Piano Trio Music": #753
Edit:
- New video clips of dancing 12-VU-Meter Array (IEC60268-17 compatible) together with all the on-screen Peak Meters of audio software tools while playing reference/sampler music tracks by JRiver MC, ADOBE Audition 3.0.1 and MusicScope 2.1.0:
____Part-1: using a typical reference/sampler music track suitable for high-Fq (treble) transient music sound: #974
____Part-2: using a typical reference/sampler music track suitable for mainly checking and tuning of low Fq (bass) transient music sound as well as total tonality Fq-SPL balance all over 15 Hz to 22 kHz: #975
Hello friends,
I always have profound nostalgia and preference for physical large glass-face VU meters. During the past several months, therefore, I have been enjoying my participation on
the thread entitled "VU Meters: Let's See 'Em!!" and on
the thread entitled " Douk VU3 Review (VU Meters)".
Now, as a follow-up of my posts
here,
here and
here, I just completed my DIY of
12-VU-Meter Array using very attractive large glass-face VU meter NISHIZAWA R-65 in my present multichannel multi-driver multi-way multi-amplifier stereo system;
In this post, I am happy to describe and share the details of this DIY-built
12-VU-Meter Array.
I assume many of you who periodically visit this project thread are well aware of that I use four HiFi integrated amplifier in this project; YAMAHA A-S3000 (driving WOs), ACCUPHASE E-460 (driving SQs), SONY TA-A1ES (driving TWs) and YAMAHA A-S301 (driving STs). (My heavy L&R sub-woofers YAMAHA YST-SW1000 has built-in amplifiers in it.)
Among the four integrated amplifiers, E-460 has nice beloved beautiful log peak power meters (not pure VU meters), A-S3000 has really nice meters which can be switched either of log peak programme (PP) mode and pure VU mode. TA-A1ES and A-S301, on the other hand, do not have any VU/PP meter.
You may agree with me that pure VU meter mode, not the PP mode, would fit very well with our air sound listening sensations; I have been always looking for the "same" nice large glass-face physical VU meters for monitoring the SP high level signals from these four amplifiers. I would like to have the relative gains of such possible VU-meter Array should fit well with the sound pressure level (gain) of actual room air sound at my listening position.
Nowadays, it has become more and more difficult, however, to find and purchase high-quality reliable large glass-face VU meters in the market. And this is why I recently participated on
the thread entitled "VU Meters: Let's See 'Em!!"
As I shared
here and
here, it was my great pleasure finding the availability of NISHIZAWA VU Meter R-65 kit in Japan. The professional-use large glass-face VU meter R-65 (W111 mm x H77 mm: glass-face W100 mm x H40 mm) has already disappeared from the product list of
Nishizawa Electric Meters Manufacturing Co., Ltd. (NEMM Co., Ltd.). Very fortunately, however, a small company SUZUDES10 issued a special contract with MEMM Co., Ltd. for small scale production and supply of their VU meter R-65, and SUZUDES10 replaces the bulb backlights with color LEDs. SUZUDES10 is also selling the R-65 VU meter unit of original bulb light as well as four different color LED ones;
http://suzudes10.shop-pro.jp/?mode=cate&cbid=2774641&csid=0
For the LED color variations, SUZUDES10 also contracted with NEMM Co., Ltd. to have white scale plate in R-65, instead of the original pale yellow one, for better LED color representations.
https://ameblo.jp/suzudes20/entry-12716821866.html
I am very happy finding such a small niche VU meter manufacturer is still alive and active in Japan, even though I do not know whether they would accept purchase order from abroad or not.
In any way, I first purchased one R-65 VU meter kit of special high-grade orange 2700K LED version, and fully tested and evaluated;
The VU Meter R-65 and its
dedicated VU amp board ATV205EXT are essentially compatible with the IEC 60268-17 VU meter Standard/Specification (3,600 Ohm, AC1.228 V0 - VU 600 Ohm: 0 VU with 1.228 V 1000 Hz, ballistic behaviors as specified by IEC), and the VU amp board ATV205EXT has further VR adjustment capability to fit with line-level input of 30 mV to 10 V, and the back panel VRs can adjust plus/minus 10 dB or more. The actual current consumption by the VU amp circuit board is about 35 mA inclusive of the LED lighting.
Edit: Please also refer to my post #545 for compatibilities with IEC 60268-17.
On the board, we can find a JRC 2073D amp module and a JRC 78M06A three-terminal regulator.
According to
their page here, they have voltage limiter circuit on the board protecting the nice VU meter R-65 from overshoot load,
i.e. higher than 1.22V 0VU value at the internal 3,600 Ohm resistance.
This VU R-65 kit is powered by AC 12V 0.5A (AC-AC adaptor), and not by DC 12V. I have discussed with them about why not by DC 12V, and they said that, for beginners DIY construction, AC 12V should be better than DC 12V avoiding the possible wrong reverse polarity connection in case of DC 12V power supply. On the board, however, they also have DC 12V power supply terminals next to the yellow-cable AC 12V terminals. As you can see, the kit board also has protection fuse chip in the AC 12V power supply yellow lines.
In total, I found the VU meter R-65 and the board ATV205EXT are well designed with nice and durable components.
Using the one kit purchased (two R-65 VU meters for L & R channels), I fully tested and evaluated the VU functionalities, especially the wide flexibility of input level adjustment, in
line-level signals, in
headphone out signals, and also in
SP high-level signals after high-to-low conversion into RCA line level by Audio-Technica's AT-HLC-130 (for which I will share in detail afterwards). Through these test and evaluation, I concluded that I can use 6 (six) of this VU R-65 kit for my DIY construction of
12-VU-Meter Array to be used in my present multichannel multi-driver multi-way multi-amplifier stereo audio setup.
I understand well that you are much curious about which signals I would like to monitor in my setup by using the DIY
12-VU-Meter Array.
1. Total sum of the digital signal (15 Hz - 25 kHz) coming from JRiver into EKIO for DSP XO/EQ processing,
i.e. whole sum of digital through signal into EKIO, which should be properly DA-converted to be monitored by
VU-01(L) and
VU-02(R).
2. Line level crossover-ed ultra-low Fq signal (15 Hz - 50 Hz) driving active sub-woofer YAMAHA YST-SW1000 to be monitored by
VU-03(L) and
VU-04(R).
3. SP high-level signal of YAMAHA A-S3000 (45 Hz - 600 Hz) driving WOs to be monitored by
VU-05(L) and
VU-06(R) by using a high-to-low converter.
4. SP high-level signal of ACCUPHASE E-460 (600 Hz - 6 kHz) driving SQs to be monitored by
VU-07(L) and
VU-08(R) by using a high-to-low converter.
5. SP high-level signal of SONY TA-A1ES (6 kHz - 25 kHz) driving TWs to be monitored by
VU-09(L) and
VU-10(R) by using a high-to-low converter.
6. SP high-level signal of YAMAHA A-S301 (
ca. 8.8 kHz - 25 kHz) driving STs to be monitored by
VU-11(L) and
VU-12(R) by using a high-to-low converter.
Furthermore, I set three strict conditions for these VU monitoring in my setup;
- The VU-meter configurations should "never" deteriorate at all the present excellent total sound quality of the system.
- The VU-meters should be placed in the end of the signal paths; the through-out signals from the VU boards should "never" be used for further listening purposes (except for special rare measurement cases, though).
- The DIY
12-VU-Meter Array should be easily moved to various positions in my listening room depending on the nature of my (our) listening and/or tuning sessions; accordingly, all of
the stereo RCA cables (7 stereo RCA cables including one auxiliary/spare cable) and
the one AC 12V PS cable going into the
12-VU-Meter Array should be about 7 m long, and the total weight should be small enough for easy position changes.
As for the AC 12V PS, I purchased and validated one AC 12V 5A transformer-type AC adaptor (INPUT: 100VAC 50/60Hz, OUTPUT: 12VAC 5A 60VA, max.41A) which can distribute AC 12V to all of the six ATV205EXT VU amp boards. I extended its 12VAC output cable in 7 m connecting to the PS distribution terminals in the
12-VU-Meter Array.
Now, under these requirements, how can I get signals in my setup to be monitored by VU meters?
1. VU-01(L) and VU-02(R)
I can create new two output panels in DSP EKIO's configuration feeding all the Input-1(L) and Input-2(R) digital signals into them, with no crossover/EQ configuration at all except for the UHF (ultra-high frequency) noise cut off filter (48 dB/Oct high-cut [Low-pass] LR filter at 25 kHz), and can feed the digital signals (L & R) into my tiny spare DAC
KORG DS-DAC-10 for only VU monitoring of its RCA line level output. Of course, EKIO can feed the digital signal into DS-DAC-10 through KORG's dedicated ASIO USB driver. DS-DAC-10's specifications, including the 10Hz - 40kHz +/-1dB Fq spec, are just more than enough only for the VU meter monitoring of the whole sum of the signal which EKIO is handling. In this case, although DS-DAC-10 is not fully in sync with my main OKTO DAC8PRO, I well tested and confirmed that there is no sync/async issue in just VU monitoring of the whole sum signal even for a continuous long time (over 12 hours) listening/tuning sessions.
2. VU-03(L) and VU-04(R); 15 Hz - 60 Hz driving SWs
In present system configuration, EKIO's crossover-ed L&R ultra-low Fq signal (15 Hz - 60 Hz) goes into DAC8PRO's CH1+CH2, and the L&R active sub-woofers YAMAHA YST-SW1000 receive the analog line-level signal by unbalanced RCA cable from the headphone line-out of DAC8PRO (CH1+CH2 under DAC8PRO's preamp/volume control) using a DAP XCALIBER XGA-18 stereo TRS-to-RCA adaptor. This means the DAC8PRO's CH1+CH2 XLR balanced out is open which can be used for VU meter monitoring using XLR-to-RCA adaptor cable (pin No.3 floated/non-connected) even if loosing 6 dB gain. The 6 dB gain loss can be easily compensated by the wide-range VRs on the ATV205 VU meter amp board.
3. VU-05(L) and VU-06(R); 45 Hz - 600 Hz driving WOs by YAMAHA A-S3000
I really would like to monitor the actual SP high-level signal driving WOs. Fortunately, A-S3000 is capable of bi-wiring SP drive having SP-A and SP-B high-level outputs. I can use SP-B high-level output into Audio-Technica's High-to-Low converter AT-HLC130 to give line-level RCA signal to be connected to the ATV205 VU meter board. Looking from amplifier, AT-HLC130 is minimal 600 Ohm load, and, therefore, no effect at all for the main SP-A output driving WOs.
It would be also nice that, if needed, I can disconnect the VU monitoring using the SP selector of YAMAHA A-S3000; SP-A, SP-B or SP-A+B. The SP-B selection disconnecting SP-A WO is also nice for possible VU meter monitoring of the signal "in silence", also if needed.
Audio-Technica's AT-HLC130 is a simpler version of AT-HLC150 which I fully evaluated and validated in my posts
#401,
#402 and
#485. The only difference between AT-HLC130 and AT-HLC150 is that AT-HLC130 does not have gain down VR on the board, but AT-HLC150 has one VR;
I believe the simpler AT-HLC130 without VR (above photo) should be better than AT-HLC150 for my present usage for only VU meter monitoring since the ATV205EXT VU meter board has wide-range (can be adjusted to 30mV to 10V) VRs on the board and also nice VRs (+/- 10dB or more) on the back panel.
Of course, I could fully evaluate and validate the specifications of AT-HLC130; it is really flat High-to-Low converter in 20 Hz - 40 kHz +/-1dB precision, and just fine for VU meter monitoring of the signals in my setup.
4. VU-07(L) and VU-08(R); 600 Hz - 6 kHz driving SQs by ACCUPHASE E-460
ACCUPHASE E-460 is also capable of bi-wire drive for SPs with SP high-level out A and B. Using another AT-HLC130 High-to-Low converter, I can do the same as I described above for
VU-05(L) and
VU-06(R).
5. VU-09(L) and VU-10(R); 6 kHz - 25 kHz driving TWs by SONY TA-A1ES
SONY TA-A1ES is a simple quasi Class-A amplifier with one SP high-level out. By branching at the SP out terminals to feed into another AT-HLC130 High-to-Low converter, I can do the same as I described above for
VU-05(L) and
VU-06(R).
6. VU-11(L) and VU-12(R); ca. 8.8 kHz - 26 kHz driving STs by YAMAHA A-S301
YAMAHA A-S301 is also capable of bi-wire drive for SPs with SP high-level out A and B. Using another AT-HLC130 High-to-Low converter, I can do the same as I described above for
VU-05(L) and
VU-06(R).
Having signals into 12 VU meters with definitely no deterioration to the present excellent total sound quality, the next critically important issue would be "How can I, how should I, adjust gains and relative gains for the 12 VU meters?"
My basic stance and requirements in this regard are as follows;
- I have little interest on "absolute" VU values. The relative VU value over the 12 VU meters would be my main interest in VU monitoring.
- The relative gains among the 12 VU meters should match the air sound pressure (gains) at my listening position.
- At the moment of the maximum (the loudest) actual room air sound pressure/volume (of course still below the system's clipping level) of full huge orchestra
fff (sfz) tutti as well as of huge pipe organ's
fff (sfz) tutti in my listening room environments, the
VU-01(R) and V
U-02(L), as well as
VU-05(L) and
VU-06(R) shall/should swing-up to around +2.8 dB red zone position.
- I shall/should not use the "through output" line level signals from the VU amp boards for further recording or any other listening purposes.
I can rather easily adjust the gain and relative gains of the 12 VU meters accordingly since I have already intensively measured the Fq responses of my multichannel multi-amplifier setup, and I have precise Fq response correlations for
line-level signals vs.
room air sound, and
SP-out high level signals vs.
room air sound, as follows;
- Frequency (Fq) responses in the completed system measured by using “cumulative white noise averaging method” under the present standard crossover configurations and relative gains_Part-1_Fq Responses in EKIO’s digital output level: #394
- Frequency (Fq) responses in the completed system measured by using “cumulative white noise averaging method” under the present standard crossover configurations and relative gains_Part-2_Fq Responses in DAC8PRO’s analog output level: #396
- Frequency (Fq) responses in the completed system measured by using “cumulative white noise averaging method” under the present standard crossover configurations and relative gains_Part-3_Fq Responses in amplifiers’ SP output level before protection capacitors: #401
- Frequency (Fq) responses in the completed system measured by using “cumulative white noise averaging method” under the present standard crossover configurations and relative gains_Part-4_Fq Responses in amplifiers’ SP output level after protection capacitors: #402
- Frequency (Fq) responses in the completed system measured by using “cumulative white noise averaging method” under the present standard crossover configurations and relative gains_Part-5_Fq Responses in actual SP room sound at listening position using one measurement microphone: #403
- Frequency (Fq) responses in the completed system measured by using “cumulative white noise averaging method” under the present standard crossover configurations and relative gains_Part-6_Summary, discussions, and a little step forward: #404,
#405-
#409
- Overhaul maintenance of super-tweeter FOSTEX T925A and further signal fine tuning thereafter: #485
- Latest best tuned total frequency response of the whole system as of January 2, 2022: #485
Even though I will not go into details here regarding my fine adjustments of gains and relative gains for the 12 VU meters, looking at the two diagrams below, you may easily understand my adjustment procedures using flat white noise and pink noise;
Now, I believe that it would be better to draw the system diagrams with 12 VU meters in it.
The present physical system setup is like this;
The 12 VU meters can be installed in the setup like this;
The new EKIO's XO configuration is like this;
and,
After having all of the above favorable preparatory work and planning, I placed purchase order for additional 5 kits each consists of R-65 VU meter (high-grade orange 2700K LED) and VU amp board ATV250EXT.
Although here I will not go into the details, the company SUZUDES10 was very much collaborative on my plan for
12-VU-Meter Array: they carefully selected 12 R-65 VU meters (including the two purchased in advance), installed the high-grade 2700K LEDs, carefully adjusted the light color and intensity over 12 VU meters, and also actually tested and burned-in all the VU meters and the VU amp boards for about non-stop 96 hours confirming LED emission color, intensity, uniformity and functionality.
I have been much impressed by such collaborative work and user oriented attitude given through a small VU manufacturer's craftsmanship in Japan. I found with my great pleasure that Japanese audiophile oriented craftsmanship still survives even in the really niche market of physical high-grade VU meters.
Then, I could move on to physical DIY design of my
12-VU-Meter Array as follows (red scale in mm);
and,
I decided to build with White Wood Veneer of 5.5, 13.0 and 16.0 mm thickness so that the whole
12-VU-Meter Array is light enough to be easily moved to various positions in my audio listening room (actual photos will be shared afterwards). The outer surfaces are to be DIY painted.
On weekend days in two months, I enjoyed my DIY of
12-VU-Meter Array.
Four of AT-HLC130 High-to-Low Converter with wiring completed;
The gains and relative gains for the 12 VU-meters were carefully adjusted by the wide-range VRs on the ATV205EX VU amp board and by the fine tuning (+/- 10 dB) VRs on the back panel of ATV205EX;
The total power consumption of the
12-VU-Meter Array is AC 12V 0.210A, only 2.52W.
I slightly modified the layout of the amplifiers and DAC8PRO on the large wide side-cabinet for nice usual/standard positioning of the completed
12-VU-Meter Array. This layout change was critical in getting approval and consent from our chief interior coordinator (my wife!);
I really like the large glass-faces of the R-65 VU-meters and the high-grade 2700K LED illumination.
As described before, with the 7-m-long RCA cables as well as the AC 12V PS cable, I can easily move the
12-VU-Meter Array depending on the nature of my (our) listening and/or tuning sessions like the several photos below;
Let me emphasize again that the function and specification, including the swing-up and swing-down transient behavior, of the large glass-face R-65 VU meter with high-grade 2700K LEDs and ATV250EX VU amp board are compatible with the IEC 60268-17 VU meter Standard/Specification (3,600 Ohm, AC1.228 V0 - VU 600 Ohm), and I am very pleased seeing the movements of the VU indicator needles very well match with my listening sensations to room air sound at my listening position (so that I carefully adjusted).
During the coming several weeks, I will continue fine tuning of the
12-VU-Meter Array while playing/listening all the tracks of
Sony Super Audio Check CD and
my latest audio sampler playlist; if needed for this, I will again measure the room air sound by using measurement microphone ECM8000.
Edit:
- Dancing video of my IEC 60268-17 compatible large glass-face DIY 12-VU-Meter Array
_____Part-1: with "High Frequency Linearity Check Track" of Sony Super audio Check CD: #750
_____Part-2: with typical "Full Orchestra Music"-1: #751
_____Part-3: with typical "Full Orchestra Music"-2: #752
_____Part-4: with typical "Jazz Piano Trio Music": #753
Edit:
- New video clips of dancing 12-VU-Meter Array (IEC60268-17 compatible) together with all the on-screen Peak Meters of audio software tools while playing reference/sampler music tracks by JRiver MC, ADOBE Audition 3.0.1 and MusicScope 2.1.0:
____Part-1: using a typical reference/sampler music track suitable for high-Fq (treble) transient music sound: #974
____Part-2: using a typical reference/sampler music track suitable for mainly checking and tuning of low Fq (bass) transient music sound as well as total tonality Fq-SPL balance all over 15 Hz to 22 kHz: #975