Posts by strum

    How do you go backwards in OS from 2.4 to 2.3?

    I put the 2.3 kaos.bin on my USB, but the KPA doesn't ask if I want to update. I assume because it is a lower version than what I have installed.

    So for purely workflow reasons, not sound quality, I changed my decision, I do want the spdif option.

    I called Apogee and they went out of their way to find one of their dealers that had a used PCI 64 card for a great!! price, so I'm all set.

    So thank you Apogee!!

    Sorry for asking a newb question but if it's being transferred digitally through S/PDIF, what's with the clock sync? Shouldn't bit for bit be transferred regardless?

    My understanding is (was) S/PDIF is be the most optimal way of transferring what actually comes out of the Kemper (no unnecessary AD/DA going on), right?

    Now another question, is there a latency in the S/PDIF connection? To stay with my present DAW I will need a coax to toslink adapter, anyone has any experience with that? Will that add latency? I'm thinking electric - optical - electric..
    Am I better off getting another (cheap) DAW that does support coax S/PDIF and just aggregate the DAW's on my Mac Mini?

    When two digital devices are transferring bits between them, one must be the clock master, and the other must lock to that master clock. If both are acting on their own clock, the transfer of bits won't be synchronized and errors will occur. The short story is the Kemper must be Master, and your spdif interface must be set to slave to incoming spdif. This is because the Kemper can only be master, because slaving hasn't been implemented by Kemper. I'm not sure if it is possible or not for them to implement that in the future???

    Yes, it is most optimal with respect to being less AD/DA going on.

    I'm new, so take this with a grain of salt. For recording, the way I planned to record if I could do spdif, was to monitor using the audio outputs on the kemper into my analog mixer, and just record the spdif, not listening to it as I play. So the only latency would be that of the Kemper which I guess is 3-4ms, and a little more if you choose fixed latency. For reamping using spdif, I am guessing there would be next to no latency as there are no AD/DA stages?

    Cheapest solution? Record and reamp with analog 1/4" inputs. Its not a big deal, just made out like there'll be better tones from SPDIF. I actually like the sound of the Kemper through 1/4" vis-a-vis SPDIF.

    Yeah, that was my final decision rather than spend more money and deal with switching back and forth between interfaces. Plus, I want to reamp through my pedalboard anyway... ;-)

    If I am new to the Kemper, wondering if I should upgrade? Will this change the sound of all the default profiles? Or does it only change the sound if you have tweaked cabinets yourself?

    Dude, that's sick!!! I've been considering the Symphony for the past few months to replace my Yamaha 01V96i but now... no way!! Yeah, the sync issues been documented for quite some time now by Apogee; seems it'd be fixed by now..

    For full disclosure, there are 3 ways to connect the Symphony I/O to your computer. USB, Thunderbridge, and PCIe card. Slaving works with Thunderbridge and the PCIe card, just not USB. But Thunderbridge is an extra $500, and PCIe is another $900. I don't have a Thunderbolt port on my computer, so that means I would have to buy the PCIe card, but I don't want to spend $900 on PCI technology that Apple has said they will never put in another computer. I will get the Thunderbridge once I get a new computer, but that is probably a year or 2 out.

    ...and thanks for the Scarlett recommendation, I will check it out.

    Yes, it's the fear subtle distortions that have convinced me this is a bad idea.

    I can forgive Kemper for not implementing slaving, but I have a harder time forgiving Apogee for not implementing slaving in USB mode on the Symphony I/O.

    It means I will be turning off my $3000 Apogee interface, and buying a $200 Roland or Native Instruments interface that can slave.

    I found this on SOS


    "However, if the receiving device is configured to use an entirely different clock source as its reference (perhaps its internal clock, or the clock from a different source) then the two devices will effectively be working independently of one another and will drift in and out of sync with each other. If you are lucky, most of the time the two clocks will be close enough that when the receiver goes looking for a sample from the source, it will find one. However, sooner or later the receiving device will look for a sample and not find one, and that's when you'll hear the click! The rate at which the clicks occur is an indication of the rate at which the two clocks are drifting relative to one another. I came across one professional installation with asynchronous clocks where the clicks only happened once every several days!"

    So I guess, my follow up question would be... if they are running independently but so close, and I'm not getting any clicks, does that mean I'm all good? I could live with a click every once in a while, and just reamp again.

    Or is it a more subtle degradation, and I'd be better off just reamping analog.


    I have an Apogee Symphony I/O that I run in USB mode. Unfortunately, using USB, the Symphony can not lock to external digital sources. You need Thunderbridge for that.

    That being said, I still hooked up the SPDIF between the Kemper and the Symphony, and I was able to record and reamp using the SPDIF connections.

    I was surprised this worked as I understand the Kemper can't lock to an external digital signal, and thus both clocks would be running independently. I called Apogee, and I was told, they are probably running so close that you aren't noticing, but you are still probably getting subtle aliasing and drift. I'm wondering if it is this, or did the Kemper OS get updated to be able to lock to an external source?