Solid State Logic SSL 2 Teardown

Written By: Sergei Pachtchenko

Published: 19/07/20

Comments: 29

Solid State Logic SSL 2 Teardown

Published: 19/07/20

Teardown

Introduction

SSL2 is the first audio interface from Solid State Logic, which is famous for its large analogue mixing consoles. What components did the legendary company use and how does the mysterious 4K button work?

What did I miss? Please leave a comment below.

Tools

Step 1

SSL 2 is a very straightforward audio interface that is easy to use and intuitive. Each function has its own analog control. Its a pleasure to use.
The audio quality as ADC is excellent. The preamplifier is very low-noise and the gain is sufficient even for dynamic microphones that are difficult to drive.
DAC is also very good, but not high end (compared to NAD D1050). I notice the difference especially in the bass response.
The headphone amplifier lacks a little power at high volumes (adds some distortion), but is sufficient for most applications.
Use a headphone with a long cord — the headphone jack is located at the back of the device along with other I/O.
Tip: If you are listening to the recorded sound, it is good to hear only the sound from the computer, not the microphone. With my old interface, I used to turn the monitor crossfade control back and forth for this purpose. With SSL 2 there is a very nice way to mute the microphone quickly: Just switch the microphone input to LINE.

Step 2

First remove the four top screws holding the top panel and the four screws at the back holding the back panel. Pop the interface out of the housing.
Do not unscrew the bottom plate. There is nothing behind that. Just a massive plastic case that smells quite unpleasant when opened. Save you some time and leave the metal bottom panel where it is.
The board is held by massive stand-offs which help to avoid flexing. There are no screws here.
The housing is made of very solid and massive ABS. Nothing else can be seen or serviced from the bottom of the unit.
The bottom plate is made of ca. 1mm thick, painted steel sheet.
The unit is very easy to open and to repair. Nice!
Self-tapping screws are used to assemble this unit. Do not overtighten during reassembly. Not made for frequent reassembly.
The unit weighs 880g. This is a lot for a sound card in a mostly plastic case. This weight and robustness are achieved by using a metal plate and an unusually thick ABS plastic case.

Step 3

The PCB is attached to the upper aluminium plate by nuts on the pots.
Use the 11 mm wrench to loosen the nuts.
Tighten just slightly during reassembly. Do not overtighten.

Step 4

The PCB is all black and has gold plated contacts and vias. SSL has two versions of this interface: SSL 2 and SSL 2+. The "+" version has more outputs and offers MIDI connectivity. For this reason, many components are missing from the circuit board shown here. Obviously, SSL uses the same PCB for both versions of the product.
Although the input sockets are combined XLR/TRS, the signal paths are separate. Nice!
SSL uses high quality, mostly Japanese, components (Alps, NJM, AKM, Nichicon, Panasonic) throughout the product. The connectors are made by Neutrik. Nice!

Step 5

There are some more op-amps there, probably for the TRS-Outs.
And the quartz.

Step 6

NJM8065 (labelled 8065 902F JRC) by Japan Radio Company. High-gain, wide bandwidth, dual operational amplifier. Data sheet.
The NJM8065 combines many of the features of the NJM4558 as well as providing the capability of wider bandwidth (10MHz typ.), and higher slew rate (4V/μs typ.) make the NJM8065 ideal for active filters, data and telecommunications, and many instrumentation applications. (From the data sheet)
BAR 43S STM. Small signal Schottky diode.
There are several resistors in the circuit: 188: 1.8 GΩ, 018: 100 MΩ, 102: 1 kΩ, 010: 1 Ω.
4K switch soldering points.
The PCB was not properly cleaned of flux residues after soldering. High quality products are usually very clean.
The 4K Legacy circuit is boosts higher frequencies and adds harmonic distortion to the sound. This analog effect can work well in live broadcasts with darker microphones such as the Shure SM7B. On the other hand, the 4K circuitry seems to introduce more noise into the signal. I recommend leaving it off for high quality recordings.
I like the idea of being able to have switchable effects in the signal path. Audio interfaces are often used in live streaming situations where it is important to be able to change the sound during the stream, and digital effects would add an unwanted delay. Perhaps SSL could integrate an analog compressor and equalizer into their next interface.

Step 7

AKM AK4621EF CODEC by Asahi Kasei Microdevices. 115dB 192kHz 24-bit 2 ch ADC & 2 ch DAC with Low Latency Digital Filter. Website, Data sheet.
The AK4621EF is a high performance 24-bit CODEC that supports up to 192kHz recording and playback. The on-board analog-to-digital converter has a high dynamic range due to AKM’s Enhanced Dual-Bit architecture. (From the data sheet)
The DAC utilizes AKM’s Advanced Multi-Bit architecture that achieves low out-of-band noise and high jitter tolerance through the use of Switched Capacitor Filter (SCF) technology. (From the data sheet)

Step 8

XMOS XU212-256-FB236 (marked XMOS U11280C20). xCORE Multicore Microcontroller. Standalone real-time RISC processor. Data sheet.
This is the actual interface which manages the whole I-O work and timings.
The xCORE200 Series is a range of 32-bit multicore microcontrollers brings the low latency and timing determinism of the xCORE architecture to mainstream embedded applications. xCORE multicore microcontrollers execute multiple real-time tasks simultaneously and communicate between tasks using a high speed network. (From the data sheet)

Step 9

MXIC MX 25L8006E M2I-12G, 8MBit SPI Flash, SOIC-8 CMOS Serial flash. Data sheet.
The 10 lines JTAG and PWR connectors are most probably used for flashing the device during production.
Those connectors are suspicious: Solid State Logic uses the same connectors for their 500 series console modules. Can the interface be used in a different setting? All connections seem to go somewhere.

this makes testing and production flow much easier. Very clever. And also, if they wanted to use these in bigger consoles - they can.

Albert -

Step 10

NJM8068 (marked 8068 906F JRC) by Japan Radio Company. Low noise bipolar input dual audio operational amplifier. Website, Data sheet.
The NJM8068 features Low distortion, high slew rate, wide bandwidth and high open-loop gain. In addition, unity-gain stable allows voltage-follower operation. These features make NJM8068 ideal for audio pre amplifier, microphone amplifier, line amplifier and other audio applications. (From the data sheet)

Step 11

NJM8080 (marked 8080 945F JRC) by Japan Radio Company. Dual operational amplifier designed for high quality audio applications. Data sheet.
The NJM8080 features high resolution and crispy-clear high frequency sound, which can fully perform the digital sound source with loss-less. NJM8080 features low noise, wide gain-bandwidth, low distortion and high output current, and various reliabilities and conveniences are improved. (From the data sheet)

Step 12

OPA1678 (marked OP1678) by Texas Instruments. Dual channel low noise low distortion operational amplifiers. Data sheet.
The OPA167x amplifiers achieve a low 4.5-nV/√Hz noise density and low distortion of 0.0001% at 1 kHz, which improves audio signal fidelity. They also offer rail-to-rail output swing to within 800 mV with a 2-kΩ load, which increases headroom and maximizes dynamic range. (From the data sheet)
The OPA1678 and operate over a very wide supply range of ±2.25 V to ±18 V or (4.5 V to 36 V) on only 2 mA of supply current to accommodate the power supply constraints of many types of audio products. These op amps are unitygain stable and have excellent dynamic behavior over a wide range of load conditions. (From the data sheet)
The OPA167x amplifiers use completely independent internal circuitry for lowest crosstalk and freedom from interactions between channels, even when overdriven or overloaded. (From the data sheet)

Step 13

NJM4556A (marked 4556A X17L JRC) by Japan Radio Company. Dual operational amplifier. Data sheet.
The NJM4556A integrated circuit is a high-gain, high output current dual operational amplifier capable of driving ±70mA into 150Ω loads (±10.5V output voltage), and operating at low supply voltage (V+ /V- =±2V~). (From the data sheet)
The NJM4556A combines many of the features of the popular NJM4558 as well as having the capability of driving 150Ω loads. In addition, the wide band-width, low noise, high slew rate and low distortion of the NJM4556A make it ideal for many audio, telecommunications and instrumentation applications. (From the data sheet)

Step 14

Richtek RT9179 (marked XA9J8) 300mA linear voltage regulator. Data Sheet.

for the l2E component is there a dataset?

Mas Pur -

Step 15

TPS65130 by Texas Instruments. Split-Rail Converter with Dual, Positive and Negative Outputs. Data sheet.
ON 842B Zener Diode.

Step 16

Full IC Identification:
You may need to enlarge it to view the text.

Step 17

The big black ones are made by Nichicon and the smaller blue ones by Panasonic. Nice!

Step 18

All potentiometers are made by ALPS (marked 203K 945C). Nice!

Author

Sergei Pachtchenko

Member since: 21/01/18

337 Reputation

27 comments

One of the best user-made teardowns I’ve seen so far! Congratulations on making your first one!

CChin - 20/07/20

Very nice photos! As a pro EE though, just wanted to correct a few misconceptions in step 6:

Flux: if they used the right type of flux, leaving it on is fine. Many switches and potentiometers can’t be “washed” because they’re not sealed (the liquid would get stuck inside), so after SMT assembly and cleaning, these are usually hand-soldered separately using “no-clean” flux - this class of fluxes is non-corrosive and safe to leave on the board permanently. The only reasons to clean flux off the board are DC leakage currents (which only matter for pA or fA measurements, nothing in the audio realm will matter at all in this way) or corrosion (if you’re not using a no-clean flux).

Resistor values: definitely no gigaohm values; leakage around the resistors is probably in the gigaohm range. These are using the EIA-96 style resistor codes, which are standard on 0603 and smaller - I can see how it would be easy to misread the “B”s as “8”s. The schematic for each channel looks something like this.

DCS - 26/07/20

nice post！ thanks man

CuteBlast SAMO - 20/09/20

Just bought it, excellent tear down reivew. Totally loved it!

Sébastien Léger - 01/12/20

Hello, I sincerly appreciate your work. Thank you from bottom of my heart for the deep teardown and most your POV. That was exquisite to read and watch and made me bought one (knowing what I buy). Your work was very appreciated here my friend! Thank You!!!!!!

Sébastien Léger - 03/12/20

So does it really have faulty IC?

https://www.gearslutz.com/board/product-...

Quoted ; After doing some digging and ordering some new parts, I fixed the issue. U25 on the PCB needed to be replaced. U25 and U26 are JRC8080 IC's and responsible for the balanced outputs on the unit. After replacing the faulty IC the unit is in tip top shape again. I have included the new plots showing the flat frequency response and THD.

Fat Lip - 28/01/21

And if the card is not detected by the computer? What part do you think is responsible for the computer's determination?

Qim - 09/04/21

thx alot for the teardown, I appreciate! I have some issues with the wobbly “Line” buttons, one of them causing some ground noise if they don’t release properly and wobbling it around usually solves it but it gets annoying. are those easy to replace/fix?

Artur - 21/08/21

Hi,

i made a mistake by connecting my guitar amp Marshall output directly to the ssl2+ … the ssl2+ do not work anymore !

I understand my mistake now …

So, I have dismantled the interface in the hope that that something can be done.

Which parts have to be removed & repaired for the SSL ? (if it’s possible)

Thank you

Daniel

Lostie DeMonde -

I think I did this too! Did you discover a fix..?

Joshua Morris -

Oh my god. Thank you so much. I couldn’t find the voltage regulator model ANYWHERE. You are the best.

Juan Martín van Keulen -

Thank you SO much for the teardown and descriptions. I was curious to know exactly what my SSL 2+ had inside.

JESUS IS CALLING YOU -

4k stays lit due to excessive input and does not work. Is there any hint?

Thanks for a very good review

tech st -

Replace U36 regulator. In some units it comes back alive, in others U36 overheats and eventually burns up again. In the latter cases I'm not sure yet what causes the regulator to burn.

Tidre Dudro -

Thanks for tis - great job. I had been suspicious of the pots and switches because they seemed light weight and 'too smooth/loose' to my touch. The main monitor big knob especially. The phantom power switches as well. The fact that you've identified high quality components is reassuring. I did buy the extended 3 year warranty as a few have reported problems with the buttons.

So far very happy with the audio quality and the 4K 'mojo' compliments my voice really nicely, exceeding my expectations..

noams -

Hello, many say that its size should be smaller, now that you have seen its interior, do you think that its size could have been compacted? (excuse my English, I'm using a Spanish / English translator)

gustavoacosta72 -

What switch is use for the HiZ Line +48 switch please help

Vanlal Rinzuala -

when i plug in ssl2+ all the lights light up, but doesnt produce any sound when connected, i have sent it to someone to fix it and they said it suffers an open circuit but the guy cant locate the exact component it occured in, he’s telling me he needs the Circuit diagram, any suggestions? Thank you!!

GHOSTO (Ghosto) -

Thanks for your inspiring Information. It guided me well during my journey and gave me the hope I was looking for Beacn mic light

Mercedes J. Vose -

Hi, thanks for an awesome tear down description. I seem to have lost my right output, might be due to +48V return. Any help to identify which components to replace? Thank you in advance.

Auriot Booyes -

AWESOME ! !

Thank you so much for this detailed teardown Sergei. Would it be possible to do the same for SSL 12? From the headquarters of SSL informed me that the SSL 12 is using a higher quality DAC, and in general the whole circuitry is upgrated compared to SSL 2.

But I really wonder how much more the SSL 12 it is improoved ???

operator dx7 -

Just few precisions :

- The XMOS chip is XU212-256-TQ128-C20 not XU212-256-FB236

- IC chip marked XA9J8 is not a RT9179 but a AP22802AW5-7 from Diodes (not a linear voltage regulator but a SINGLE CHANNEL POWER DISTRIBUTION LOAD SWITCH)

egdev - 21/06/23

Very good. I saw that pins 1 and 5 were inverted in relation to the datasheet, I researched until I found something I could buy to test, it would be the RT 9742.

Aslem Santos Vale -

здравствуйте, можно с вами как то связаться по консультации ремонта данного девайса?

Sergey Kaltyshev -

Hello, I believe that the IC 306 has the wrong reference. I have a board like this for repair and when consulting the datasheet of RT 9179 (XA9J8 or XA9JB) pins 1 and 5 are inverted (1 input and 5 output). In the interface that I have, the marked code is XA0XB. After much querying I managed to find what appears to be the correct code, it's here https://www.richtek.com/m/Home/Design%20... the evaluation board and the datasheet. The code would be RT 9742.

Aslem Santos Vale -

Great teardown thanks! Are you sure the TPS65130 is for the 48V? It seems more likely to be for the main op amp supply, often around -+6v.

Greg - 31/08/23

thanks for the picc etc.. great stuff. ssl2 great little machine.

Anton Eizer -