Hi,
I am just starting out with this DIY audio lark! As the owner of an ARCAM Black Box 50 DAC, I was wondering if there was any inexpensive and relatively straightforward component changes to inprove the product. I am broke at the moment, so will not be considering anything "boutique"!! and can't quite run to a (pre-built) clock upgrade for my ARCAM Alpha 6 at the moment.
I have inspected the daughterboard that is in the DAC, and which I assume is where the D to A process takes place. The other "main" board has the trannies on it and a few caps, but looks more like the analogue output stage.
Here is a list of parts found in the machine. I have seen some quite complimentary comments about the Yamaha chip, but could I drop a modern and better performing part into the PCB (if the pinout and specs were the same)??
Components on BB50 Daughter Board:
Caps:
Rubycom M334, M704, M3460, M511, plus non-polar 16v 100uf / 50v 10uf
Evox PFR (680pJ 63-), (220 pJ 63-)
9517 CMK 100-
ICs:
(1x) Yamaha YM3623B
(x2) Philips 74HC00N 958510PS Hnn9444PD
(x2) Philips 74HC74N 968100PS Hnn9448 E
(x1) Philips 74HC86N 914090PS Hnn9409PB
(x2) Philips 74HCU04N 747440PS Hnn9435PB
(x3) Philips NE5532N 0152H04 950 9NL
(x1) P53AF DS9637ACN
(x1) “BB” PCM69AP 95 9421 E3 000 J
Crystal:
IQDKD 20.000
Any comments or pointers are welcome. If it's all too much for my level, then I'll look at starting a simpler project.
Thanks for your thoughts and expertise
Jon
I am just starting out with this DIY audio lark! As the owner of an ARCAM Black Box 50 DAC, I was wondering if there was any inexpensive and relatively straightforward component changes to inprove the product. I am broke at the moment, so will not be considering anything "boutique"!! and can't quite run to a (pre-built) clock upgrade for my ARCAM Alpha 6 at the moment.
I have inspected the daughterboard that is in the DAC, and which I assume is where the D to A process takes place. The other "main" board has the trannies on it and a few caps, but looks more like the analogue output stage.
Here is a list of parts found in the machine. I have seen some quite complimentary comments about the Yamaha chip, but could I drop a modern and better performing part into the PCB (if the pinout and specs were the same)??
Components on BB50 Daughter Board:
Caps:
Rubycom M334, M704, M3460, M511, plus non-polar 16v 100uf / 50v 10uf
Evox PFR (680pJ 63-), (220 pJ 63-)
9517 CMK 100-
ICs:
(1x) Yamaha YM3623B
(x2) Philips 74HC00N 958510PS Hnn9444PD
(x2) Philips 74HC74N 968100PS Hnn9448 E
(x1) Philips 74HC86N 914090PS Hnn9409PB
(x2) Philips 74HCU04N 747440PS Hnn9435PB
(x3) Philips NE5532N 0152H04 950 9NL
(x1) P53AF DS9637ACN
(x1) “BB” PCM69AP 95 9421 E3 000 J
Crystal:
IQDKD 20.000
Any comments or pointers are welcome. If it's all too much for my level, then I'll look at starting a simpler project.
Thanks for your thoughts and expertise
Jon
I have done a little digging and have ID'd some of the ICs on the D to A daughterboard.
I kind of assume that if you replace some of these with "better" components (from RS etc) that you would improve the overall result if the specs remained the same. Anyway, comments are gratefully received!!
Jon
They are as follows:
ICs
(1x) Yamaha YM3623B
LSI device that receives and plays back the Digital Audio Interface Format signals that are transferred between digital equipment. It has an internal PLL.
(x2) Philips 74HC00N 958510PS Hnn9444PD
Quad 2-input NAND gate
FEATURES
ƒnOutput capability: standard
ƒnICC category: SSI
GENERAL DESCRIPTION
The 74HC/HCT00 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL).
They are specified in compliance with JEDEC standard no. 7A.
The 74HC/HCT00 provide the 2-input NAND function.
(x2) Philips 74HC74N 968100PS Hnn9448 E
Dual D-type flip-flop with set and reset;
positive-edge trigger 74HC/HCT74
FEATURES
Output capability: standard
ƒnICC category: flip-flops
GENERAL DESCRIPTION
The 74HC/HCT74 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT74 are dual positive-edge triggered, D-type
flip-flops with individual data (D) inputs, clock (CP) inputs,
set (SD ) and reset (RD ) inputs; also complementary Q and
Q outputs.
The set and reset are asynchronous active LOW inputs
and operate independently of the clock input. Information
on the data input is transferred to the Q output on the
LOW-to-HIGH transition of the clock pulse. The D inputs
must be stable one set-up time prior to the LOW-to-HIGH
clock transition for predictable operation.
Schmitt-trigger action in the clock input makes the circuit
highly tolerant to slower clock rise and fall times.
(x1) Philips 74HC86N 914090PS Hnn9409PB
Quad 2-input EXCLUSIVE-OR gate 74HC/HCT86
FEATURES
Output capability: standard
ICC category: SSI
GENERAL DESCRIPTION
The 74HC/HCT86 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT86 provide the EXCLUSIVĵ-OR function.
(x2) Philips 74HCU04N 747440PS Hnn9435PB
Hex inverter 74HCU04
FEATURES
ƒnOutput capability: standard
ƒnICC category: SSI
GENERAL DESCRIPTION
The 74HCU04 is a high-speed Si-gate CMOS device and is pin compatible with low power Schottky TTL (LSTTL).
It is specified in compliance with JEDEC standard no. 7A.
The 74HCU04 is a general purpose hex inverter. Each of the six inverters is a single stage
(x3) Philips NE5532N 0152H04 950 9NL
NE/SA/SE5532/5532A Internally-compensated dual low noise
operational amplifier
DESCRIPTION
The 5532 is a dual high-performance low noise operational amplifier.
Compared to most of the standard operational amplifiers, such as
the 1458, it shows better noise performance, improved output drive
capability and considerably higher small-signal and power
bandwidths.
This makes the device especially suitable for application in
high-quality and professional audio equipment, instrumentation and
control circuits, and telephone channel amplifiers. The op amp is
internally compensated for gains equal to one. If very low noise is of
prime importance, it is recommended that the 5532A version be
used because it has guaranteed noise voltage specifications.
FEATURES
Small-signal bandwidth: 10 MHz
Output drive capability: 600 W, 10 V RMS
Input noise voltage: 5 nV//Hz (typical)
DC voltage gain: 50000
AC voltage gain: 2200 at 10 kHz
Power bandwidth: 140 kHz
ƒnSlew rate: 9 V/ms
Large supply voltage range: ¡Ó3 to ¡Ó20 V
Compensated for unity gain
(x1) P53AF DS9637ACN
DS9637A
Dual Differential Line Receiver
General Description
The DS9637A is a Schottky dual differential line receiver
which has been specifically designed to satisfy the requirements
of EIA Standards RS-422 and RS-423. In addition, the
DS9637A satisfies the requirements of MIL-STD 188-114
and is compatible with the International Standard CCITT recommendations.
The DS9637A is suitable for use as a line receiver
in digital data systems, using either single ended or
differential, unipolar or bipolar transmission. It requires a
single 5V power supply and has Schottky TTL compatible
outputs. The DS9637A has an operational input common
mode range of ¡Ó7V either differentially or to ground.
Features
Dual channel
Single 5V supply
Satisfies EIA standards RS-422 and RS423
Built-in ¡Ó35 mV hysteresis
High input common mode voltage range
High input impedance
TTL compatible outputs
Schottky technology
Extended temperature range
(x1) Burr Brown PCM69AP 95 9421 E3 000 J
FEATURES
l 18-BIT RESOLUTION DUAL AUDIO DAC
l EXCELLENT THD PERFORMANCE:
0.0025% (¡V92dB) at F/S, K Grade
1.0% (¡V40dB) at ¡V60dB, K Grade
l HIGH S/N RATIO: 110dB typ (IHF-A)
l DUAL, CO-PHASE
l SINGLE SUPPLY +5V OPERATION
l LOW POWER: 75mW typical
l CAPABLE OF 16X OVERSAMPLING
l AVAILABLE IN SPACE SAVING
16-PIN DIP OR 20-PIN SOIC
l OPERATING TEMP RANGE:
¡V2ƒ¥¢XC to +8ƒ¥¢XC
l EXTREMELY LOW GLITCH ENERGY
DESCRIPTION
The PCM67 and PCM69A dual 18-bit DAC are low
cost, dual output 18-bit BiCMOS digital-to-analog con-verters
utilizing a novel architecture to achieve excel-lent
low level performance.
By combining a conventional thin-film R-2R ladder
DAC, a digital offset technique with analog correction
and an advanced one-bit DAC using first order noise
shaping technique, the PCM67 and PCM69A achieve
high resolution, minimal glitch, and low zero-crossing
distortion.
PCM67 digital offset occurs at bit 9, making it ideal for
high-performance CD players. PCM69A digital offset
occurs at bit 4, making it an excellent choice for digital
musical instruments and audio DSP.
Both PCM67 and PCM69A operate from a single +5V
supply. The low power consumption and small size (16-
pin PDIP or 20-pin SOIC) make these converters ideal
for a variety of digital audio applications.
Advanced 1-Bit BiCMOS Dual 18-Bit
DIGITAL-TO-ANALOG CONVERTER
I kind of assume that if you replace some of these with "better" components (from RS etc) that you would improve the overall result if the specs remained the same. Anyway, comments are gratefully received!!
Jon
They are as follows:
ICs
(1x) Yamaha YM3623B
LSI device that receives and plays back the Digital Audio Interface Format signals that are transferred between digital equipment. It has an internal PLL.
(x2) Philips 74HC00N 958510PS Hnn9444PD
Quad 2-input NAND gate
FEATURES
ƒnOutput capability: standard
ƒnICC category: SSI
GENERAL DESCRIPTION
The 74HC/HCT00 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL).
They are specified in compliance with JEDEC standard no. 7A.
The 74HC/HCT00 provide the 2-input NAND function.
(x2) Philips 74HC74N 968100PS Hnn9448 E
Dual D-type flip-flop with set and reset;
positive-edge trigger 74HC/HCT74
FEATURES
Output capability: standard
ƒnICC category: flip-flops
GENERAL DESCRIPTION
The 74HC/HCT74 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT74 are dual positive-edge triggered, D-type
flip-flops with individual data (D) inputs, clock (CP) inputs,
set (SD ) and reset (RD ) inputs; also complementary Q and
Q outputs.
The set and reset are asynchronous active LOW inputs
and operate independently of the clock input. Information
on the data input is transferred to the Q output on the
LOW-to-HIGH transition of the clock pulse. The D inputs
must be stable one set-up time prior to the LOW-to-HIGH
clock transition for predictable operation.
Schmitt-trigger action in the clock input makes the circuit
highly tolerant to slower clock rise and fall times.
(x1) Philips 74HC86N 914090PS Hnn9409PB
Quad 2-input EXCLUSIVE-OR gate 74HC/HCT86
FEATURES
Output capability: standard
ICC category: SSI
GENERAL DESCRIPTION
The 74HC/HCT86 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
The 74HC/HCT86 provide the EXCLUSIVĵ-OR function.
(x2) Philips 74HCU04N 747440PS Hnn9435PB
Hex inverter 74HCU04
FEATURES
ƒnOutput capability: standard
ƒnICC category: SSI
GENERAL DESCRIPTION
The 74HCU04 is a high-speed Si-gate CMOS device and is pin compatible with low power Schottky TTL (LSTTL).
It is specified in compliance with JEDEC standard no. 7A.
The 74HCU04 is a general purpose hex inverter. Each of the six inverters is a single stage
(x3) Philips NE5532N 0152H04 950 9NL
NE/SA/SE5532/5532A Internally-compensated dual low noise
operational amplifier
DESCRIPTION
The 5532 is a dual high-performance low noise operational amplifier.
Compared to most of the standard operational amplifiers, such as
the 1458, it shows better noise performance, improved output drive
capability and considerably higher small-signal and power
bandwidths.
This makes the device especially suitable for application in
high-quality and professional audio equipment, instrumentation and
control circuits, and telephone channel amplifiers. The op amp is
internally compensated for gains equal to one. If very low noise is of
prime importance, it is recommended that the 5532A version be
used because it has guaranteed noise voltage specifications.
FEATURES
Small-signal bandwidth: 10 MHz
Output drive capability: 600 W, 10 V RMS
Input noise voltage: 5 nV//Hz (typical)
DC voltage gain: 50000
AC voltage gain: 2200 at 10 kHz
Power bandwidth: 140 kHz
ƒnSlew rate: 9 V/ms
Large supply voltage range: ¡Ó3 to ¡Ó20 V
Compensated for unity gain
(x1) P53AF DS9637ACN
DS9637A
Dual Differential Line Receiver
General Description
The DS9637A is a Schottky dual differential line receiver
which has been specifically designed to satisfy the requirements
of EIA Standards RS-422 and RS-423. In addition, the
DS9637A satisfies the requirements of MIL-STD 188-114
and is compatible with the International Standard CCITT recommendations.
The DS9637A is suitable for use as a line receiver
in digital data systems, using either single ended or
differential, unipolar or bipolar transmission. It requires a
single 5V power supply and has Schottky TTL compatible
outputs. The DS9637A has an operational input common
mode range of ¡Ó7V either differentially or to ground.
Features
Dual channel
Single 5V supply
Satisfies EIA standards RS-422 and RS423
Built-in ¡Ó35 mV hysteresis
High input common mode voltage range
High input impedance
TTL compatible outputs
Schottky technology
Extended temperature range
(x1) Burr Brown PCM69AP 95 9421 E3 000 J
FEATURES
l 18-BIT RESOLUTION DUAL AUDIO DAC
l EXCELLENT THD PERFORMANCE:
0.0025% (¡V92dB) at F/S, K Grade
1.0% (¡V40dB) at ¡V60dB, K Grade
l HIGH S/N RATIO: 110dB typ (IHF-A)
l DUAL, CO-PHASE
l SINGLE SUPPLY +5V OPERATION
l LOW POWER: 75mW typical
l CAPABLE OF 16X OVERSAMPLING
l AVAILABLE IN SPACE SAVING
16-PIN DIP OR 20-PIN SOIC
l OPERATING TEMP RANGE:
¡V2ƒ¥¢XC to +8ƒ¥¢XC
l EXTREMELY LOW GLITCH ENERGY
DESCRIPTION
The PCM67 and PCM69A dual 18-bit DAC are low
cost, dual output 18-bit BiCMOS digital-to-analog con-verters
utilizing a novel architecture to achieve excel-lent
low level performance.
By combining a conventional thin-film R-2R ladder
DAC, a digital offset technique with analog correction
and an advanced one-bit DAC using first order noise
shaping technique, the PCM67 and PCM69A achieve
high resolution, minimal glitch, and low zero-crossing
distortion.
PCM67 digital offset occurs at bit 9, making it ideal for
high-performance CD players. PCM69A digital offset
occurs at bit 4, making it an excellent choice for digital
musical instruments and audio DSP.
Both PCM67 and PCM69A operate from a single +5V
supply. The low power consumption and small size (16-
pin PDIP or 20-pin SOIC) make these converters ideal
for a variety of digital audio applications.
Advanced 1-Bit BiCMOS Dual 18-Bit
DIGITAL-TO-ANALOG CONVERTER
The NE5532's are the most obvious to replace by better types like OPA2604. I prefer the CS8412 receiver but it is not pincompatible.
Change the opamps, maybe some caps for BG and close the cover. 😉
Better is to build a complete new DAC !
Change the opamps, maybe some caps for BG and close the cover. 😉
Better is to build a complete new DAC !
Thanks for your comments, J-P.
The Op Amp change is within my limits, and I can get hold of the pieces. Are the caps you're talking about the "Black Gate"?? I'm new to this, sorry.
I saw a very interesting DAC from Scott Nixon - very amazing what you can get out of a small box, isn't it??
😀
Rgds
Jon
The Op Amp change is within my limits, and I can get hold of the pieces. Are the caps you're talking about the "Black Gate"?? I'm new to this, sorry.
I saw a very interesting DAC from Scott Nixon - very amazing what you can get out of a small box, isn't it??
😀
Rgds
Jon
Hello Jon,
Black Gate is a brand of electrolytic capacitors. They are expensive but practically always give better results if you replace the old ones for them.
Change the opamps anyhow, you won't regret it. Makes the unit easier to sell if you build the very good Scott Nixon DAC 😉
Do a search and you will find plenty of opinions of his DAC ( all positive ! ).
Black Gate is a brand of electrolytic capacitors. They are expensive but practically always give better results if you replace the old ones for them.
Change the opamps anyhow, you won't regret it. Makes the unit easier to sell if you build the very good Scott Nixon DAC 😉
Do a search and you will find plenty of opinions of his DAC ( all positive ! ).
It's been a long time......
but I did complete my DacKit - Using Black Gates, Wima, 0.1 % resistors etc. Very good it is too!
I think the Arcam Black Box sensed something. It was that box that was tripping out my amps, not the integrated I am using as a pre. Anyway, that cost me over 100GBP for Arcam to repair my "handiwork ON THE AMP!
Still, I learned much about doing the best diagnosis you can, and not jumping to conclusions!! The Right channel on the Black Box was intermittent (tripping the amp safety relays) and now has completely failed.
Does anyone have any suggestions on where to start looking with the multimeter? I really don't want to send it back to Arcam, but if I can repair it, then perhaps it will find a new home on eBay etc. (or maybe I just could not bear to part with it!! 🙂 ).
I have looked at the boards (digital and analogue) to see if there are any signs of scorched components etc, but everything looks fine.
All suggestions gratefully received!! 🙄
Cheers
Jon 🙂
but I did complete my DacKit - Using Black Gates, Wima, 0.1 % resistors etc. Very good it is too!
I think the Arcam Black Box sensed something. It was that box that was tripping out my amps, not the integrated I am using as a pre. Anyway, that cost me over 100GBP for Arcam to repair my "handiwork ON THE AMP!
Still, I learned much about doing the best diagnosis you can, and not jumping to conclusions!! The Right channel on the Black Box was intermittent (tripping the amp safety relays) and now has completely failed.Does anyone have any suggestions on where to start looking with the multimeter? I really don't want to send it back to Arcam, but if I can repair it, then perhaps it will find a new home on eBay etc. (or maybe I just could not bear to part with it!! 🙂 ).
I have looked at the boards (digital and analogue) to see if there are any signs of scorched components etc, but everything looks fine.
All suggestions gratefully received!! 🙄
Cheers
Jon 🙂
Update......................
I found the culprit!!
A dead NE5532 on the daughter board. Replaced and functions fine. 🙂
I picked up a Delta 250 transport and second BB50 (I thought this was unfortunate because I already have one) for a decent price. Replaced the toothed gear in the CD that had failed - hence the price - with a spare I had "in stock". It plays very nicely indeed.
I have an idea to compare the 2-box player with my Alpha 6 with upgraded daughter (DAC) board. Then also to mod one of the BB50s and to compare with the stock version. Sounds like fun! 🙂
I opened both BB50s (one an early model, one about a year or 2 older) to compare the innards. I saw some interesting differences!! 😱
The early model has Black Gates on the outputs of the power board and the DAC board. The 5532s are all Signetics as opposed to Philips. Plus there are different voltage regulators - LM317T on the older model. 😎
The soldering on the back looks as tidy as the rest of the board - and that leads me to believe that it may be a factory fit rather than an aftermarket upgrade. Anyone able to shed some light on this??
Also, has anyone compared Evox Rifa PFR pulse film caps with Wima FKP?
Cheers
Jon
I found the culprit!!
A dead NE5532 on the daughter board. Replaced and functions fine. 🙂
I picked up a Delta 250 transport and second BB50 (I thought this was unfortunate because I already have one) for a decent price. Replaced the toothed gear in the CD that had failed - hence the price - with a spare I had "in stock". It plays very nicely indeed.
I have an idea to compare the 2-box player with my Alpha 6 with upgraded daughter (DAC) board. Then also to mod one of the BB50s and to compare with the stock version. Sounds like fun! 🙂
I opened both BB50s (one an early model, one about a year or 2 older) to compare the innards. I saw some interesting differences!! 😱
The early model has Black Gates on the outputs of the power board and the DAC board. The 5532s are all Signetics as opposed to Philips. Plus there are different voltage regulators - LM317T on the older model. 😎
The soldering on the back looks as tidy as the rest of the board - and that leads me to believe that it may be a factory fit rather than an aftermarket upgrade. Anyone able to shed some light on this??
Also, has anyone compared Evox Rifa PFR pulse film caps with Wima FKP?
Cheers
Jon
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