JBL M2 / SUB18 and BSS BLU-160

[christo]

I’m new at this M2/BSS stuff and have read most of the threads in the various forums, I just need some clarity with my thinking.

Is it possible to use a BSS BLU-160 and load both the M2 and SUB18 tunings into it?

• Assuming 2 analog output cards 1 for the M2 pair and the other for the SUB18s

Trying to be flexible with amplifier selection, as I’m a little concerned with the I-Tech amplifier fan noise. If I go the I-Tech route I’d would have to build a sound proof cabinet...

Has anyone run pair of SUB18s with an I-Tech 12000HD?

Chris

[Champster]

I’m new at this M2/BSS stuff and have read most of the threads in the various forums, I just need some clarity with my thinking.

Is it possible to use a BSS BLU-160 and load both the M2 and SUB18 tunings into it?

• Assuming 2 analog output cards 1 for the M2 pair and the other for the SUB18s

Trying to be flexible with amplifier selection, as I’m a little concerned with the I-Tech amplifier fan noise. If I go the I-Tech route I’d would have to build a sound proof cabinet...

Has anyone run pair of SUB18s with an I-Tech 12000HD?

Chris

Hi Chris,
I would definitely steer clear of the Crown products for a home listening environment. Unless they can be tucked away in a closet, they will drive you nuts. I guess the 160 would be fine but members like Grumpy will know better than me. The other thing you can do is to call 800-9310-2357 for Harman (BSS) tech support. The guys there will help you with the software but could also direct you to the right BSS unit. The SUB18 doesn't really have a file like the M2s do. You'll need to do that integration yourself through London Architect. I'm glad to help once you get your stuff set up.
Paul

[Wayner]

I seem to recall the Sub18 preset is part of the M2 preset. A dropdown menu asks if you are configuring M2 with or without Sub18.

Fan noise is an interesting problem. The Crown amps have loud fans, no getting around that. They pretty much have to be isolated from the listening area. Blu160 or 800 series can be modified to have a fan noise similar to a laptop. But I ended up thinking that was a little too much ambient noise and went with a Blu50. But the Blu50 is a 4 channel device so it won't handle the Sub18s. (and I don't use Sub18s)

A software (vs. hardware) type solution, such as Acourate, is another possibility. One of these days I'm going to work on an implementation. There is a very good thread started by DallasJustice on using this approach with a M2/Sub18 speaker system on another forum, AudiophileStyle. Also, Mitchco, who participates on Lansing Heritage, produced a very fine presentation on digital room correction that includes M2/Sub18 as an implementation example. "Understanding the State of the Art Digital Room Correction" Another article on this subject is "Integrating Subwoofers with Stereo Mains using Audiolense."

So much fun to be had with a digitally enabled speaker system.

[Mitchco]

Thanks @wayner.

In addition to DallasJustice, jtwrace went with the Audiolense software DSP route and biamped his M2's and added 4 subs, with all drivers time aligned using linear phase digital crossovers, along with digital room correction: https://www.avnirvana.com/threads/my...e-jbl-m2.9425/

A video walkthrough of the process here: https://youtu.be/yfGAUvyvdNU?t=4196

jtwrace had the BSS unit and then went with the all DSP software approach. You could PM him at avnirvana to get his thoughts...

PS. this is of course assuming one is using a computer based audio system. Good luck!

[christo]

Thanks everyone @Champster, @Grumpy, @Wayner and @Mitchco for your input.

I’ve actually been working towards a Digital M2/SUB18 system for a few years now and finally decided “What are you waiting for…” and ordered the speakers. The M2s should be here in a couple of days the SUB18 are back ordered – until who knows when…

Here’s what I’ve collected over the last few years, the speakers were the last pieces.


What I’ve been fussing with recently are the amplifiers and how to integrate them in to the system. Hence my questions on BSS Soundweb London and Crown I-Tech.

I was looking at the I-Techs as a simple solution (load the tuning and Go) to power the M2s and if it weren’t for the fan noise, done deal. Which then lead me to looking at the BSS BLU-800/160 to enable the use of other amplifiers.

I have a pair of Crown XTi 4002s which I’ll use for the subs but not sue what to do with the M2s

The only other amps I have are a Krell Evo 302 and a Parasound A21+ both in the 300w/Channel range. Just not sure how they would sound/integrate together. The Krell I don’t have a problem with it, I’ve been using it for years on the top end of my 43xx monitors and it sings!

Have been reading and watching videos on the topic of DSP for a while now, read and seen everything mentioned. Kinda copied DallasJustice’s Lynx Hilo/Benchmark DX solution from his various posts.

So, it’s back to Plan A, Acourate Digital Filters, @Mitchco I’ll be talking to you in the near future.

[sebackman]

Hi Christo,

A couple of thoughts.

Notwithstanding what Dallas Justice may add I have tried many DSP units over the years and always gravitate back to the BSS Soundweb units for standalone DSP units. Worth noting is that my contacts within the BSS world clearly states that the Crown build in units are not the same in HW or SW. I don’t know the validity of that, but they (and I) would take a BLU-160 any day over a build in unit (I have both).

JBL also demoed the M2’s (and 67000) with a BSS BLU160 and Mark Levinson amps in their NYC showroom back when. Probably the differences are small (if audible) and other things of course also weigh in. After all JBL did sell the M2’s to studios with the HD amps so that is probably also an excellent combo.

Albeit that the BSS HW may not be as advanced and silent (noise and S/N) as some others, particular within the HiFi field, units the SW is better than most. The algorithms just sound better. At least to me and my measuring rig.

No doubt, computer based systems used By Dallas Justice and others can provide similar or better results but at a cost of time and complexity. I decided against it in my system due to the complexity and the never-ending computer OS updates that keep demanding updates on drivers and stuff.

With a stand alone DSP you can feed digital signal from a “always-on” raspberry Pi running Volumio OS which pops up as a Spotify and Tidal connect in your iPad or iPhone. Very convenient. I use a cheap Topping D10S as USB to SPDIF converter. Briliant device. (Topping D10 Balanced Review (USB DAC) | Audio Science Review (ASR) Forum)

On Crown fans and other;
Crowns do often have noisy fans so, as pointed out above, unless you can put the amps in another room (I have mine in the basement and cables under the floor) or dare to swap in silent fans (read Noctua and may void warranty) you may want to look elsewhere. We typically put Noctua in ours. The newer ones with temp controlled speed go silent at idle and the fans noise is off-set by music when playing loud.

The better Crown amps provides a lot of quality power for the money while I personally prefer analogue amps for the M2’s. I do not hesitate to use digital for the subs. In fact, I use a Crown CTS3000 for my subs (not with M2’s), but always use analogue class A/B for the full range speakers.

The newer digital amps are probably equally good or potentially better (like the Benchmark AHB2, the newer Hypex modules) but I personally do not really like the sound of the former generation. I get listening fatigue after a while which never happens with proper A/B units. (Review and Measurements of Benchmark AHB2 Amp | Audio Science Review (ASR) Forum)

My findings are that you do not need enormous amounts of power to make the M2’s sing but you do need amps that can provide lots of current, ie 2 ohm stable. Often those do provide lots of wattage but you will do just fine with a 300W @ 8 ohms amp if it can handle lots of current (ie your Krell and similar). The perfect amp would almost double the power at 4ohms and double again at 2 ohms. That is at least my findings with all these big woofers with large 4” voice coils, albeit the 2216 is 3” (but long).

Using a BSS or any other separate DSP system will allow usage of any amp you like. I even have some friends running tube amps (beats me why…) with M2’s. I would suggest that you use the same amp for the woofers (2216) and the drivers as differences between models and makes may be more difficult to address than most think if you want to get the most out of your factory M2’s. I never mix amp type with DSP active tops (acronym for anything with a sub 😊 )

On BSS fans
Same story here. Noctua has a 5V 40x40x20mm fan that fits perfect, and you really only need 2 fans at the power supply side (factory is 4 fans) . We turn them around, so they extract air and have not had any problems on many units we have converted. They go acceptable silent by that mod.

On BSS BLU50
There are 3 versions of BSS HW. The fixed I/O (8x8) units in the BLU100-BLU103. The do have fans. The BLU160 and BLU800 that are buildable "chassis" and take 4 cards with 4 channels on each card. They can be analogue or digital in or out. Or any mix. They also have the BLU50 (ref above) unit which is a fixed 4x4 and totally fan-less.

All the fixed I/O units have the same DSP power while the 160 and 800's chassis have twice that which is rarely needed unless you go FIR filters or large multi channel systems

However, all of these do have what BSS call the BLU-LINK which is a low latency 256 channel digital interface. This gives ability to add inputs and outputs as needed. You can digitally interlink all BSS and as many Crown units as needed if they are equipped with BLU-LINK.

BLU-LINK also have free standing analogue input and output expansions units. They are called BLU-BIB for input and BLU-BOB for output and are stand-alone units with 8 analogue channels in or out + BLU-LINK BLU-LINK is really only a standard RJ45 Ethernet cable between the units. Bot units are fan-less. Break-In / Break-Out Boxes | BSS Networked Audio Systems (bssaudio.com)

This means that you can without any problem use a fan-less BLU50 for M2 + subs by adding a BLU-BOB unit for 8 additional analogue output channels. DSP power is not a problem for that setup.

Input connectivity.
In your picture you may have several DA and AD conversions. BSS has separate box called the BLU-USB which is really an asynchronous USB soundcard that you connect to your computer and it will offer an all-digital BLU-LINK connection to your BSS unit. This means that you avoid any ADC in the loop. BLU-USB | BSS Networked Audio Systems (bssaudio.com)

As the BSS is 41bit internal you can without problem use the BSS as your volume control and control it by computer, manual or remote controlled potentiometer (all needed connections is available on the rear side of all BSS units, 8 analogue controls and 8 digital controls beyond the sound input and output) or by iPhone/iPad over WiFi (Harman offers an app for it).

So, computer direct to BLU-USB (USB cable) to BLU DSP unit of choice (Ethernet cable) and direct on to power amplifiers with balanced or single ended analogue cables. Sell Lynx and Benchmark units. 😊. You will need to add some kind of controllable volume control in the BSS.

I use IR remote controlled ALPS motor potentiometers for that, a few $ for the kit from China, does not matter as no sound goes through there. Just 3 thin cables to the BSS and all set (or even 2…).

Or you can go crazy as me and get digital input cards in the BSS (AES/EBU or SPDIF) and feed digital sound from a digital source of choice and take the DSP processed signal out from the BSS again via digital output cards and feed a DAC’s of your choice. I use an Okto Pro8 (Okto Research).

Unless you want to embark on the computer SW route the BSS avenue is really flexible. I would start with a BLU50 and a BLU-BOB (no fans) which gets you 4 analogue channels in and 12 analogue balanced channels out (you only use 6 unless you will do 4 subs). If you want to go digital in just add a BLU-USB between your digital source (streamer, computer or Pi) and the BSS and a SW volume control in the BLU50 (+ a potentiometer or rotary controller as per above).

The DAC’s in the BLU50 are pretty good but should you later want to go with a separate DAC setup you need and expansion cabinet (not a second DSP) that provides for digital output cards and that connects to your BLU50 via BLU-LINK, a BLU120 + 2pcs digital output cards =8 channels SPDIF or AES/EBU. Sell the BLU-BOB

I have a BLU120 + 2 digital (and 2 analogue) output cards connected to my BLU800 on my all-digital JBL 3-way 5.2 HT.

The neat thing is that you can go step by step and most BSS stuff is readily available on the Bay for reasonable prices.

My 25 cents
//Rob

[christo]

Thanks for you post Rob; I know how much time it takes to write these up.

I’ve viewed most of the video training on the Harmon web site regarding Audio Architect, Crow Amps and BBS gear. Your explanation/experience with of all the various BSS integration options is appreciated and it tied up a lot of loose ends I had.

As far as PC based audio being complex, I guess it depends on your back ground. I started out (retired now) in software engineering and then later system integration in call centers. In the larger call centers 3,000+ agents the systems deployed easily spanned a few hundred servers. Trouble shooting these types of systems is loads of fun let me tell you .

I hear you about the using the same amplifiers for the M2, Paul also mentioned this and I do subscribe to this philosophy.

I have Krell Evo 600s but they’re in my K2 system which I finally dragged in to the digital age by selling the Krell 525 CD player (hadn’t been used in 3+ years) and replacing it with a Sony HAP-Z1ES. My wife considers this her system as whenever I start some type of audio project sooner or later, she asks “you’re not messing with or selling” the “good ones” (her name for the K2s) are you? Wonder if I can trade her a Parasound for 2 Krell .

I got tired of having to re-wire systems when I wanted switch speakers (K2/43xx), so I got a pair of Crown XTi 4002s for the bottom end of the 43xx. With the Krell 302 on top the combination worked well. So, I’m kind of reluctant to use the Evo 600s for the M2s, going to have to figure something out…

Chris

[christo]

Just an update to this thread:

I was able to finally get the M2s up and running! many thanks to @Champster for selling me his BSS-BLU-800 and SUB18s. It was a PIA to organize the shipping to north of the border and really appreciate Paul sticking with me through this process.

The BSS unit with London Architect is really fun to work with took me about 2 weeks to figure it out. Not much documentation on the web but I finally found a document that got me going (i.e. how to load and run designs) - 2 days later I realized the document was inside the help pages in the LA software .

I highly recommend using the BBS product with the M2s - it really is flexible in so many ways:

• Allows for the selection of your choice of amplifiers – any consumer amp of any power will work there is no need for 1,000-watt amps unless you want to blow your ears off
• The LA software allows for easy integration of other devices in your set up (i.e. Anti-Mode 8033S-II)
• Supports multiple speaker and equipment combinations all that is required is a different design in LA.

I use a DSPeaker Anti-Mode 8033S-II to calibrate the subs to the room this unit really works well as it allows you to place the subs as space permits – which is an issue with the SUB18s. With the Anti-Mode DSP processing it adds 2.7 ms to delay to the signal which is enough to mess with the sound stage/imaging no matter what the Anti-Mode documentation says. The M2s as they are positioned 3’ in front of the subs so I added 5.7 ms of delay, and bang the imaging and sound stage snap in to place. It is uncanny how much of a difference it makes without the delay the SQ is uninspiring with the delay it is magical! the sound envelops you and is mesmerizing.

With the BLU-800 and all its I/O cards I was able to connect my K2s and integrate them with the SUB18s. I have enough amplifiers on hand so I don’t have to rewire anything. Just select the LA design appropriate to the speakers and turn on the associated amps – I love it!

Still on the lookout for a BSS BLU-USB mine is still on back order, and I do have a digital input card I’m going to install in the BLU-800.

Next up is to develop digital filters using Acourate but of course I’m going to have to learn how to take measurement with REW.

//Chris

[christo]

In an effort to reduce the number of analogue/digital conversions in my audio chain I installed a digital input card in my BSS BLU-800. I’ve connected the Lynx Hilo to the BSS unit via AES/EBU (110 Ω cable) and I’m finding the interface clicks, pops and crunches intermittently.

I’ve locked down the sample rate at 96 kHz from JRiver across the USB into the Hilo, the Hilo out to the BSS via AES/EBU and the digital card interface in London Architect displays 96 KHz.

I was under the impression the the sample rate and synchronization could be pulled out of the audio/data stream in the AES/EBU protocol – I may have been wrong.

Is an external word-clock required to synchronize the two devices Lynx Hilo and the BSS BLU-800?

Or am I missing something else.

[sebackman]

Make certain that you have enabled the sample rate converter in the BSS. Should not be any problem with 96 in. Have had it for years.

[christo]

Make certain that you have enabled the sample rate converter in the BSS. Should not be any problem with 96 in. Have had it for years.

Not sure if I understand “enabled the sample rate converter” are these not enabled by default?

You would bypass them on the digital car interface by clicking on the “Bypass Sample Rate Conversion” button which would then assume require an external word-clock source.

Here’s a screen shot of my digital card interface Sample Rate is 96 kHz and the Bypass Sample Rate Conversion button is NOT enabled.

[christo]

The only other place I’ve found reference to Sample Rates is on the properties of the BSS BLU-800 unit. Which I’m assuming will change the BSS unit'd main board clocking frequency from 48 to 96 kHz. I don’t think this is what you are referring to as when I changed it to 96 kHz LA wanted to upgrade the firmware which I declined to do.

Any other suggestions?

[sebackman]

The settings for the input card looks fine. With the sample rate converter active the internal clock speed of the BSS should not matter. I run my 800 at 48kHz with 44,1, 48, 88,2 and 96kHz digital input. And I do think they are turned on by default as you say. I have tried external clock but it turned out to be difficult to get to work and no measurable/audible improvement. Are you running 16, 24 or 32 bits input out from the Hilo? The BSS cannot handle 32 bits so it will truncate which can be audible. Try 16 or 24 bits. The Hilo source seem to be or AES native? If not, some sources can be to high impedance and may need a SPDIF to AES converter to work.I use a Meridian processor and a Raspberry Pi4 via a Topping D10 (both SPDIF out) as digital sources and both works fine.Just a stupid thought. I saw that the Hilo is XLR AES out but is it balanced digital or just coax (single ended) via XLR. If only single ended I typically do the connection between earth and minus on the BSS input plug. Maybe worth a try?Beyond that it should work unless your Hilo uses some high tech clock shifts to reduce jitter or so. The BSS is pretty robust but not always up to date with the latest SW gadgets.Keep us updated with the progress. I have several of them operational and can maybe replicate the problem (minus the Hilo) if needed.

[christo]

Thanks for the information

I talked with Lynx support and the Hilo puts out 24-bit word length, both analog and digital outputs. They also confirmed that a SPDIF to AES converter is not required.

The AES/XLR cable I’m using does have a separate ground from the positive and negative wires so no need to jumper ground from the negative wire at the Phoenix connector.

The other thing Lynx support mentioned is that I could use the Wordclock out from the Hilo to the BLU-800 (i.e. without an external clock). I ordered some BNC cable/connectors which should arrive next week and I’ll give it a try - really do not want to have to go with an external clock.

The end solution for the system would be the BSS-USB but have not had any luck trying to find one for the last 18 months, not sure how Harman expects to do business with no BBS or Crown equipment anywhere.

In my research I can across this web page that talks about external clocking - really good information on the topic and does shed light on this.

...and no measurable/audible improvement.

https://www.soundonsound.com/techniq...al-master-cloc

Sound on Sound - Does Your Studio Need a Digital Master Clock?

[christo]

I resolved the issue this week, there was never a problem with the Lynx Hilo, BSS BLU-800 or the AES protocol it had to do with my computer setup.

I run VMware Workstation and have 3 virtual desktops besides the host system running most of the time. One of the virtual desktops I use for all things related to digital audio London Architect, REW, Acourate, etc.

I was running the London Architect design from the virtual desktop (i.e. not from the BLU800) as well as the Hilo and JRiver software. For some reason the digital signal occasionally gets corrupted, it can happen relatively fast i.e. within a single song or the music can play long as 50 minutes before the crunch.

I left the London Architect design running in the VMWare image and ran the Hilo and JRiver from the laptop which I usually use as my music server. No more problems with running the digital (AES) interface between the Hilo and BSS unit they performed flawlessly at 96 kHz.

Yes, it was worth the effort to remove the extra digital to analog conversion between the Hilo and the BSS. The sound improvement is with micro-dynamics which seem to get lost with having go digital, analog, digital and back to analog when not running digital directly into the BSS unit.

Thanks for your help, Rob.