JBL SDP-55 Audio/Video Processor Review

[mv038856]

Have you disabled Dirac, all trims and EQ (if any) and upmixers?

Hi, thanks for the hint… I had not checked before, but luckily, EQ/Dirac was off and the sound mode was Digital Stereo with no upmixer active.

 

[Andysu]

Hi, thanks for the hint… I had not checked before, but luckily, EQ/Dirac was off and the sound mode was Digital Stereo with no upmixer active.

Show a picture bit wider of the JBK SDP-55 with the scope and leads and what it is connected to and the amplifiers and the speakers Quint: For that you get the head, the tail, the whole damn thing. show me the whole thing and what it is that you want from it.

 

[Zooqu1ko]

Hi, thanks for the hint… I had not checked before, but luckily, EQ/Dirac was off and the sound mode was Digital Stereo with no upmixer active.

That might leave the trims as a cause. Could you check if the ratio is (roughly) constant independent of the frequency?

 

[mv038856]

Show a picture bit wider of the JBK SDP-55 with the scope and leads and what it is connected to and the amplifiers and the speakers Quint: For that you get the head, the tail, the whole damn thing. show me the whole thing and what it is that you want from it.

That might leave the trims as a cause. Could you check if the ratio is (roughly) constant independent of the frequency?

Thanks for your responses!
The measurements were done taking XLR pin 1 as common probe ground and connecting the probe tips to pins 2 and 3. I expected the two signals on a symmetrical output to be exact opposites, which includes equal voltages, in other words they would mirror each other perfectly. As noted, my SDP-55s left XLR output does not meet that expectation. I think the measurements as such are not the cause for the voltage difference, as the same measurement approach via the Dante output and DA conversion in the Tascam ML-16D (everything else unchanged) does not show any delta.
As outlined in post #260 my conclusion is that while not looking nice, I don‘t expect the voltage difference to have an adverse effect on the performance, so the case is closed for me. Just interesting to see the different approaches of Tascam and JBL/Harman regarding an XLR output signal.
Thanks again!

Markus

 

[Archaea]

Does the SDP-55 Synthesis processor have the ability to chose your JBL speaker and have 'tunings'? I thought I read that somewhere in the past, but I don't see it in the manual? I have JBL CBT 70J-1 speakers, and thought I recalled you could select your matching JBL speakers with a JBL processor to help apply a baseline EQ/limiter that JBL provides. Perhaps that's for a different product all together?

 

[Krobar]

Does the SDP-55 Synthesis processor have the ability to chose your JBL speaker and have 'tunings'? I thought I read that somewhere in the past, but I don't see it in the manual? I have JBL CBT 70J-1 speakers, and thought I recalled you could select your matching JBL speakers with a JBL processor to help apply a baseline EQ/limiter that JBL provides. Perhaps that's for a different product all together?

You need the more expensive SDP-75 for that.

 

[Flak]

We now have available the new 3.1 update of Dirac Live (for both Windows and Mac) which includes a fix for a Dirac Live Bass Control issue.
Kindly take into account that it's a release candidate only so it is subject to eventual changes.
All fellow forumers who are interested in testing it can contact us by opening a ticket here:
https://confluence.dirac.services/display/DLS/Dirac+Live+Support

Thanks for your time!
Flavio

 

[Blackdevil77]

Anything potentially change for this processor since the time of the review? Any firmware updates fix or improve some of the shortcomings? Anyone experience any “popping and crackling” like I read about when these were released?

 

[Blackdevil77]

Apparently there was a change to the XLR board in these. I wonder if that revision would of helped/improved the problem with the noise floor.

 

[Zooqu1ko]

Apparently there was a change to the XLR board in these. I wonder if that revision would of helped/improved the problem with the noise floor.

I was unable to find any references to that. Could you provide links? Thanks.

 

[Blackdevil77]

I was unable to find any references to that. Could you provide links? Thanks.

They're discussing it in this thread, last page. This is the first I've seen of it as well

JBL Synthesis SDP-55 (16ch, 9.1.6 Atmos Surround Sound Processor) | Page 248 | AVS Forum

"There was a hardware revision to the XLR board which fixed the popping on start-up, mute and unmute. AFAIK this revision made its way to manufactured units from about June 2020 so all UK units should be the later revision.
-Krobar"

 

[hwest]

This is a review and detailed measurements of the audio performance of the JBL SDP-55 AVP home theater processor. It was kindly purchased by a member and drop shipped to me for testing first. It arrived about two months ago. The SDP-55 costs US $6000.

Note: our company Madrona Digital is a Harman (and hence JBL) dealer. Our business though is almost entirely custom installation in commercial and high-end real estate. So we don't do much business with them for typical products I review here (and the company is totally separate from this website). That said, we can source Harman gear and the member indeed purchased this through us. So assign as much bias as you like to this review.

The SDP-55 has a very elegant, modern and serious look:
View attachment 81570

The menus and graphics are super responsive which is great. The large rotary volume control is nice but a bit too light for my taste. Then again it allows you to rotate it quick and watch the display respond quickly to it.

The back panel shows what a modern AV processor should look like:

View attachment 81571

16 channels are balanced output are nicely provided and no legacy video inputs and such. Harman acquired Arcam a few years ago and this unit shares a lot with that platform with the exception of Dante digital audio which I did not have the ability to test.

The unit comes with a lit remote control. To my surprise, after putting a pair of Duracell batteries in it, it would not work. I checked the batteries and they were fresh. Still, I tried another pair and it still did not work. On a hunch, I put in the no-name batteries that came with it and it worked with those! The reason? The Duracell batteries' positive tip is shorter than Chinese no-name batteries. With some battery holders, e.g. cheap Chinese LED flashlights, the molding keeps the tip just far away enough to not make a contact with the positive terminal. Well, the same is true here sadly. So best to stuck on no-name batteries or use a different remote. This is the first AV product I have seen with this problem by the way!

The unit comes with a letter saying it was opened and firmware upgraded. So I proceeded to do my testing that way. Once finished, with owner's permission and warning that last time I tried to update an Arcam AVP it hung, I proceeded to update the firmware here from JBL Synthesis website. I put the update on a flash thumb drive and put it in the back. Followed the procedure and update started. It said updated the "Net" and then some USB error popped up and it rebooted to operating form. Knowing that this was not the full update, I followed the instructions once again to update using the network (yes, including setting HDMI and IP to "ON").

As with Arcam, it took a good 2 hours (!) to do its thing, only to hang in the same spot: "LCD writing...." And writing it did for another hour or more. On Arcam I power cycled the unit and it recovered by restoring the old version. On the SDP-55 it simply said "Erasing LCD...." and that is all it would. Multiple power cycles, disconnecting power cables, etc. did nothing. Search online produced no hits either. On a hunch again, I put the thumb drive back in there and this time, it proceeded to update the LCD reliably!!! It rebooted and all was well with it. A quick dashboard run showed audio performance was the same.

I don't think there is a worse thing than an expensive product bricking itself and that is almost where I was. Looking at long, log list of bugs they addressed, this product from software and testing point of view seems like quite a mess.

There were other issues that had me going mad at first. Every time I would start a new test with my Analyzer, the unit would refuse to produce audio. I was going crazy until I realized if I changed inputs it would produce other again. I had to wait until it fully locked onto the unused input, switch back to HDMI to have it produce audio.

AVP DAC Audio Measurements
When I tested the ARCAM AVP, I went back and forth with the company a few times and in the process narrowed some of the performance issues there. I took advantage of that knowledge to test the AVP. Let's start with Coax S/PDIF input, bypassing any issues with HDMI:

View attachment 81575

I opted for 3.8 volt output as the next notch up on volume (79) gave me 4.2 volts and reduced performance a bit.

Most of you don't use Coax but HDMI so let's plug in the HDMI cable BUT NOT USE IT AS AN INPUT:
View attachment 81577

Notice how our SINAD sunk 4 dB. T hat is due to noise level shooting up some 15 db! Again, let me remind you that this is an identical test with Coax as input. All I have done is hook up my PC HDMI output to the SDP-55 UHD input but not selecting. Mere connection of my HDMI output to the SDP-55 causes noise to bleed into the output of the DAC.

Arcam's response to this was that I had created a "ground loop" with my HTPC. Never mind that there is no mains frequency peak that would indicate a ground loop. The noise is broadband and encompasses a range up to a few hundred hertz. They said that they test using a portable HDMI signal generator that is operated on batteries. Naturally that device is generating a cleaner source than my PC. I explained to them that consumers don't use portable HDMI generators as their source and that they need to design their equipment so that it is immune to vagaries of HDMI. They did not respond. And here we are with the JBL version doing exactly the same thing.

Anyway, to make forward progress let's test with HDMI as the input and adjusting the input to give us 4 volts:

View attachment 81579

Naturally the noise is there still and reduces the performance of the unit to below a number of mass market AVRs:
View attachment 81580

FYI grounding the SDP-55 to my normally floating Audio Precision balanced inputs (as it should be), reduced the noise a bit and raised SINAD a couple of dB. If you have noise issues in your system, you may want to do the same (I used the pre-out RCA shield for grounding, other places did not work).

There is some good news here in the form of very nice levels of output without clipping:

View attachment 81583

While you do lose performance above 3.4 volts, it is not too bad up to some 8 volts which should let you drive very low gain amplifiers.

Signal to noise ratio naturally is not that great:

View attachment 81584

IMD distortion test versus level shows typical design issue with ESS implementation which we have been free of in desktop DACs in the last year:

View attachment 81585

I had to run the Multitone test using Coax. AP software doesn't have good output buffering and it underruns sometimes as it did here with HDMI causing errors. So this is with Coax input which was very similar to HDMI while it did work:
View attachment 81586

Very strange shape with high noise floor to boot.

DAC filter performance is poor:
View attachment 81587

I like to see at least 90 to 100 dB attenuation, not 60 dB. This allows fair bit of out of band signal to be produced by the unit which screws up the performance of the THD+N versus frequency:

View attachment 81588

We know a lot of that is due to filtering because when I change the sample rate to 192 kHz (green), most of the problem goes away (since out of band signals are outside of the measurement bandwidth of 90 kHz). But even then performance is too low relative to even cheap desktop DACs (dashed blue).

Linearity is rather poor:

View attachment 81589

Note how Coax did much worse here. The reason is that the device seems to mute its output with signal below -90 dBFS. It would flash the sample rate on the display. I reported this to Arcam as well with no response.

Finally, jitter and noise is very bad on Coax input:

View attachment 81593

The high level noise floor of the unit should have masked a lot of sins but the problem is bad enough where that did not occur (with HDMI and certainly not with Coax).

Conclusions
Some people think I relish in seeing poor measurements but I have to tell you it is the opposite: it is depressing to see a device fail so much both operationally and from performance of point of view. I usually don't share my work with my wife but in this case I had to express my frustrations to her last night as the thing bricked itself. Ruined my evening and morning for that matter until I figured out how to get it working again.

From performance point of view, there is no question the device lacks proper design verification, more than a year after it was announced. And surely has very low target performance where it blends in with mass market products at much lower price.

There is some good news in there with high output level before clipping -- something we struggle to see in just about any AV processor receiver.

I debated a lot what rating to give the SDP-55: beheaded Panther or "I don't know" one. From functionality and reliability, the beheaded one is definitely deserved and hence its inclusion. On general performance, you have a balanced processor with general SINAD performance that is "not broken." So I gave it up one step up by including the I don't know panther as well.

Personally I would not buy this unit, nor recommend it. But the picking is slim in high-end processors with 16 channels of balanced output so I let you decide if you want to buy it.

-----------
As always, questions, comments, recommendations, etc. are welcome.

Per above I am depressed after doing this review. I am going to drawn out my sorry by going and picking tomatoes in the hot sun from our garden. To the extent you think some money may cheer me up as well, here is how you can donate to the site : https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

This helps with my decision on the JBL.

 

[TemploAztlan]

This helps with my decision on the JBL.

So what was your decision? I'm considering the SDP 55, Arcam AV41 and Anthem AVM70.

 

[Newman]

I think his point was that the review shows so many failings that his decision on the JBL is made for him!

 

[Daka]

I think treating processors same as stereo integrated amps is a mistake. From his reviews Denon x3700h/x4700h is super clean pre out great AVR and Arcam is rubbish. Funny enough whoever had both would never pick former over the latter. from stereo to multi channel performance Arcam absolutely demolishes Denon. So it looks like it doesn’t matter how clean the signal is when it comes to processor performance. Also when it comes to Amirm I sense a little bit bias towards Denons as he did work closely with them in his review before publishing what would be a bad review, vs quite the opposite with Arcam.

 

[peng]

Also when it comes to Amirm I sense a little bit bias towards Denons as he did work closely with them in his review before publishing what would be a bad review, vs quite the opposite with Arcam.

That is absolutely untrue!! In his review of the Arcam AV10 he said right in the beginning:

Notes: our company Madrona Digital is a dealer for Harmanowns Arcam so feel free to read any level of bias in my review. As a courtesy, I sent a copy of my measurements to Harman/Arcam engineering a week ago. Alas, I have received no feedback. Meanwhile I had to return the unit to its owner.

Arcam AVR10 Review

This is a review and detailed measurements of the Arcam AVR10 7.2 channel Audio/Video Receiver (AVR). It was purchased by a member and kindly drop shipped to me. AVR10 costs US $2,500. Notes: our company Madrona Digital is a dealer for Harman which owns Arcam so feel free to read any level of...

www.audiosciencereview.com

 

[voodooless]

from stereo to multi channel performance Arcam absolutely demolishes Denon.

How? Why?

 

[Daka]

That is absolutely untrue!! In his review of the Arcam AV10 he said right in the beginning:

Arcam AVR10 Review

This is a review and detailed measurements of the Arcam AVR10 7.2 channel Audio/Video Receiver (AVR). It was purchased by a member and kindly drop shipped to me. AVR10 costs US $2,500. Notes: our company Madrona Digital is a dealer for Harman which owns Arcam so feel free to read any level of...

www.audiosciencereview.com

My bad if indeed that’s what happened. When I read it it seemed like they weren’t given same curtesy as Denon was

 

[Daka]

How? Why?

Should only comment on my experience but found many people claiming exactly the same who went from Denon to Arcam.
Stereo performance of Arcam is so good I don’t have a need for separate integrated amp (using Purifi external amps though), also channel separation is much better. much better dynamic range. Not to mention dirac/base management, Audysey I found severely lacking at least the form it was on x4700h and 6700h.
I haven’t heard myself or anyone else commenting top of the line Denon/Marantz so can’t say how it compares. quite often differences are minimal and bias can take over, if you have one, but not if there is big difference. Even internal amps in Arcam are much better. Technically if comparing rrp it shouldn’t be a surprise, but since I can see many Arcams discounted massively that would be a no brainer choice to me.
With new lineup of Denons and Marantz’ when they get dirac - one big difference will be addressed - question how will they perform - I’m curious myself tbh. But still no details what DACs they use.
Experience with Arcam will rely on where is it coming from, they had a tone of software issues at the launch, now all good with minor issues here and there but no equipment is free of them

 

[Daka]

That is absolutely untrue!! In his review of the Arcam AV10 he said right in the beginning:

Arcam AVR10 Review

This is a review and detailed measurements of the Arcam AVR10 7.2 channel Audio/Video Receiver (AVR). It was purchased by a member and kindly drop shipped to me. AVR10 costs US $2,500. Notes: our company Madrona Digital is a dealer for Harman which owns Arcam so feel free to read any level of...

www.audiosciencereview.com

I haven’t seen this review to be honest - was referring to av40 one which seemed to be published without reaching out to Arcam and Arcam reached out to him afterwards after seeing review. With Denon Amirm showed great patience, quite possibly still Denon has people who spend time to work with reviewers closely while Arcam doesn’t - it’s a boutique company really.