The No.1 Website for Pro Audio
Clocking Coordination Hedd, Burl, Apollo
Old 19th February 2020
  #1
Lives for gear
 
proxy's Avatar
 

Clocking Coordination Hedd, Burl, Apollo

Hi, I need your expert advice.

Want to get a Hedd 192, but want to confirm proper clocking strategy with my setup before buying.

Current clocking flow is:
Burl B2 (SPIDF) Apollo x8 (Thunderbolt) Apollo 8

-

If I add Hedd to this setup, would this clocking flow work?:

Hedd AD (SPDIF) Apollo x8 (Thunderbolt) Apollo 8 (SPIDF) Hedd DA
and
Hedd (WC) Burl B2 (SPIDF) Apollo 8

-

Or should I be clocking the Burl straight off the Apollo 8 since that's where it's sending SPIDF?:
Apollo 8 (WC) Burl B2 (SPIDF) Apollo 8
Old 20th February 2020
  #2
Lives for gear
As long as 1 is the master and the rest are slave it doesn’t matter which way or who.

Also you don’t need to clock the same gear twice with 2 different cables (aka I don’t understand why the Apollo is listed twice).

A device can only get clock from 1 source at a time.
Old 20th February 2020
  #3
Lives for gear
 
proxy's Avatar
 

Quote:
Originally Posted by brew View Post
As long as 1 is the master and the rest are slave it doesn’t matter which way or who.

Also you don’t need to clock the same gear twice with 2 different cables (aka I don’t understand why the Apollo is listed twice).

A device can only get clock from 1 source at a time.
Thanks for jumping in.

Apollo 8 is listed twice because it's receiving clock from Apollo x8, but is also getting audio from the Burl via SPDIF.

The Apollo 8 can't follow the Burl, because the Apollo 8 is following the Apollo x8, which is following the Crane Song.

And Burl can't follow the Apollo 8 because it is only sending (digital audio) to the Apollo 8.

So, based on what you're saying:
For Apollo 8 to follow x8, *and* get audio from Burl without clicks, Burl should follow the original clock source, the Crane Song, because Apollo 8 ultimately gets its clock from there too?
Old 20th February 2020
  #4
Lives for gear
I send my Burl B2 to an Apollo x8 via spdif. I clock them both via an external Black Lion clock. Truthfully, I don't hear any difference between that or any any other internal combo of clocks but I haven't done strict A/B comparisons.
Old 20th February 2020
  #5
Lives for gear
 

Quote:
Originally Posted by Dayo View Post
I send my Burl B2 to an Apollo x8 via spdif. I clock them both via an external Black Lion clock. Truthfully, I don't hear any difference between that or any any other internal combo of clocks but I haven't done strict A/B comparisons.
Would love to hear if you can find any differences with an a/b. Do you send clock over BNC cable in addition to spdif?

I have a Burl B2 ADC going into an Apollo Twin X via spdif for both conversion and clock; I am not sure if sending clock over spdif is okay. I think I’m hearing some “clicks” in the audio every once in a while but I have to test further
Old 20th February 2020
  #6
Lives for gear
 

Quote:
Originally Posted by Dayo View Post
(...) Truthfully, I don't hear any difference between that or any any other internal combo of clocks but I haven't done strict A/B comparisons.
...which is quite 'normal': claims about external clocks or a specific clocking scheme making a huge (or even just a very subtle) difference are mostly wishful thinking - myths get debunked by a properly conducted blind listening a/b/x and null tests!

it's good practice to use the first a/d converter in the entire signal chain as the master clock but with more complex setups, there are plenty of situations/occasions when this ain't possible or desirable so use a distributor where applicable or for redundancy in critical situations...

(to prevent the entire rig from coming down when a single piece of gear fails)

...but for a simple setup with just a few pieces of gear chained together, an external clock and/or a wordclock distributor is a waste of money!
Old 21st February 2020
  #7
Lives for gear
 
chrischoir's Avatar
 

Quote:
Originally Posted by proxy View Post
Hi, I need your expert advice.

Want to get a Hedd 192, but want to confirm proper clocking strategy with my setup before buying.

Current clocking flow is:
Burl B2 (SPIDF) Apollo x8 (Thunderbolt) Apollo 8

-

If I add Hedd to this setup, would this clocking flow work?:

Hedd AD (SPDIF) Apollo x8 (Thunderbolt) Apollo 8 (SPIDF) Hedd DA
and
Hedd (WC) Burl B2 (SPIDF) Apollo 8

-

Or should I be clocking the Burl straight off the Apollo 8 since that's where it's sending SPIDF?:
Apollo 8 (WC) Burl B2 (SPIDF) Apollo 8
You need to clock with BNC world clock via daisy chain. You use the S/PIDF only for audio
Old 21st February 2020
  #8
Lives for gear
Only some converters are improved with external clocking because they have a crappy internal clock. SSL Alpha link is a good example. Most good converters are not changed much by the clocking however it's done.

The other thing I think makes a minor help is if the A/D converters are the master. In that way the A/D converters operate exactly as designed. In some units external clocking was a secondary consideration after they designed the unit. D/A units are designed to have an external digital signal sent to them. But again, these are problems created when the manufacture tries to make things on the cheap somehow.

With the units you are listing, I bet it makes no change how you get it done. However, given the choice, I would use the Burl as the master because I trust the quality control of burl and it's your best quality A/D (IMHO)
Old 22nd February 2020
  #9
Lives for gear
 
proxy's Avatar
 

Thanks for the replies. I went down the rabbit hole a bit more on this topic, and it’s clear that it’s not very clear.

All manner of manufacturers, publications, experts and other seemingly well-informed people, each with their own unique configurations and perspectives, have reasonable arguments and evidence that seems to completely contradict each other.

Here’s what I observed...

Standards are separate from form factor—for example, SPDIF can be coax, or optical. But when the form factor is not specified, most people seem to assume SPDIF is coax. More people than not seem to think favorably of Optical for transferring both audio and clock. Fewer people seem to trust coax for reliably transferring both audio and clock.

Some people think a good AD should be the master clock for multiple downstream devices connected in sequence (serial). Others think it’s better with a master clock connecting to all devices directly (parallel). Others think BNC T-connectors work fine (serial/parallel hybrid).

Some think a dedicated, high-quality clock can improve even a good I/O device in a single-device setup. Some think it can be detrimental, because the work done on the internal clock of the I/O device is often more reliable than the work done to receive external clock. Depending on the device, it seems each of these situations could be true.

I actually ended up getting a Burl DA at a descent price, so I will try the following:

Burl AD as master, sending SPDIF and BNC to x8.
Apollo 8 follows the x8 via Thunderbolt.
Two Rosetta 800s follow the Apollos via ADAT (no BNC)
Burl DA follows x8 via BNC, and gets SPIDF audio from it.

If the Rosettas are unhappy with ADAT doing audio and clock I will try a T-connector on the x8, so the two Apollos drive three BNCs.

Thanks for your help.
Old 4 weeks ago
  #10
Lives for gear
I am not suprised that ADAT clocking creates a problem. My first digital system was an O2R and ADAT's. The clock system was not stable. Had to reboot about every 8 hours. My ears became fine tuned to hear the smallest pop or click. To the point I can tell when the clocking is not perfect by just the way it sounds. Very difficult to describe.

With the SSL alpha link (Adat flavor), I found that the converters sounded better by turning off the ADAT inputs. My conclusion from that was that the ADAT word clock protocol is not very robust. Allowing the converters to NOT contend with an ADAT signal allowed them to work better.
Old 4 weeks ago
  #11
Gear Maniac
 

Does anyone know how much jitter the Burl clock generates? I’ve looked and haven’t seen an answer for that anywhere on the Burl website. You’d want to clock with the converter that has the lowest jitter spec if I were you
Old 4 weeks ago
  #12
Lives for gear
Quote:
Originally Posted by proxy View Post
I actually ended up getting a Burl DA at a descent price, so I will try the following:

Burl AD as master, sending SPDIF and BNC to x8.
Apollo 8 follows the x8 via Thunderbolt.
Two Rosetta 800s follow the Apollos via ADAT (no BNC)
Burl DA follows x8 via BNC, and gets SPIDF audio from it.
Sure that’ll work but I don’t know why you’d have these redundant connections. You don’t need the BNC because you can clock off SPDIF directly. The BNC is superfluous.
Old 4 weeks ago
  #13
Lives for gear
 

I’m using a Burl B2 ADC into an Apollo cia toslink spdif...I have noticed some clicks happening My last recording and wondering if it’s a result of not having a separate wordclock connection via BNC. Burl says that wouldn’t be a reason; I’ll have to see if I can recreate the issue. But are clicks/pops related to clocking?
Old 4 weeks ago
  #14
Lives for gear
 
proxy's Avatar
 

Clocking Apollo x8 off of SPDIF coming from Burl was giving me pops.

Adding a BNC for WC from Burl to Apollo x8, and clocking the x8 off of WC eliminated the pops.

May be unique to this setup, but seems to be consistent with other people's comments about SPDIF clocking.

Also, now that I have it set up, I can say that I prefer the x8 outputs when clocked off of the Burl ADC, but I prefer output to Burl DAC over Apollo x8.
Old 4 weeks ago
  #15
Lives for gear
 
MIKEHARRIS's Avatar
Am I wrong to think the always overlooked WC distribution amp should be included in these setups ?

Like antenna distros for wireless...not as rewarding as a new shiny box...but those pesky pops & clicks are no more.
Old 4 weeks ago
  #16
Lives for gear
 

Got the system working perfectly sending both digital signal and clock via toslink/spdif to my apollo Twin X without a separate wordclock connector. I think I may have had some settings in console off last time I tried,
Old 4 weeks ago
  #17
Lives for gear
Quote:
Originally Posted by mikoo69 View Post
I’m using a Burl B2 ADC into an Apollo cia toslink spdif...I have noticed some clicks happening My last recording and wondering if it’s a result of not having a separate wordclock connection via BNC. Burl says that wouldn’t be a reason; I’ll have to see if I can recreate the issue. But are clicks/pops related to clocking?
Are the optical ends of the cables or equipment clean? Any kinks in the cable. Is the optical cable a good one (flexible)?

Those cables can go bad easy if not treated gently.
Old 4 weeks ago
  #18
Lives for gear
 

Quote:
Originally Posted by elegentdrum View Post
Are the optical ends of the cables or equipment clean? Any kinks in the cable. Is the optical cable a good one (flexible)?

Those cables can go bad easy if not treated gently.
I have it working now but it is a cheap cable. Will look for a more robust one. Any suggestions?
Old 4 weeks ago
  #19
Quote:
Originally Posted by proxy View Post

Also, now that I have it set up, I can say that I prefer the x8 outputs when clocked off of the Burl ADC, but I prefer output to Burl DAC over Apollo x8.
Interesting.......

So, do you mind telling us how would you describe the difference between the 3 (Apollo native, Apollo clocked to the Burl, and Burl output). What do you prefer about the Burl output?
Old 4 weeks ago
  #20
Lives for gear
 
proxy's Avatar
 

The output midrange seemed more focused with each improvement. Like a subtle veil lifted.

These are all pretty subtle differences mind you, but definite differences.

Kind of reminds me of the difference between a classic fender amp or pickup and modern boutique variations. The newer ones seem a bit more vivid.

Quote:
Originally Posted by blayz2002 View Post
Interesting.......

So, do you mind telling us how would you describe the difference between the 3 (Apollo native, Apollo clocked to the Burl, and Burl output). What do you prefer about the Burl output?

Last edited by proxy; 4 weeks ago at 04:31 PM..
Old 4 weeks ago
  #21
Quote:
Originally Posted by proxy View Post
The output midrange seemed more focused with each improvement. Like a subtle veil lifted.

These are all pretty subtle differences mind you, but definite differences.

Kind of reminds me of the difference between a classic fender amp or pickup and modern boutique variations. The newer ones seem a bit more vivid.
Cool thanks for the update.
Old 3 weeks ago
  #22
Lives for gear
 

Quote:
Originally Posted by proxy View Post
The output midrange seemed more focused with each improvement. Like a subtle veil lifted.

These are all pretty subtle differences mind you, but definite differences.

Kind of reminds me of the difference between a classic fender amp or pickup and modern boutique variations. The newer ones seem a bit more vivid.
Just tried clocking the Twin X off the Burl via SPDIF to compare the playback sound. It's very subtle but I do hear a slight more open midrange when clocked to the Burl...barely perceptible...

Both Burl and Universal Audio suggested I clock off the Apollo for playback as I'm not using the ADC while tracking, and the internal clock of the Apollo would be better (assuming the idea behind that is use the clock from the source that is doing the conversion). Really though, this is splitting hairs...I'll probably clock off the Burl for playback a bit longer to see if I feel it makes enough of a difference, but I may be upgrading to an X8 anyway, so...
Old 3 weeks ago
  #23
Gear Addict
 

I use my Burl adc as a master clock vis SPDIF to clock the clarett 8pre thunderbolt. Wow my clarett 8pre outpost sounds tighter and more present on the midrange. All my reference ableton instruments so better with this configuration.
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump