Octa Capture and SONAR X1

that unit is mic or line in/out no >?

Just use the line in and not the mic pre for your octa and youll bypass its mic pres
Cj

You need to make 1/4 to xlr cables ... http://www.mediacollege.c...ion/xlr-jack-mono.html

Am I correct in saying that if you use the xlr connectors on the octa-capture, you are using the octa-capture pres, and if you use the 1/4 connectors on the octa-capture, you're not?

I looked in my Octa-Capture manual and nothing in there about bypassing preamps.  Just the technical specs such as imput impedance, levels, etc.

thats different !! and is stupid if they did that !!

A few things...

With most inexpensive interfaces, the gain control is functional regardless of whicih input you use (mic or line). The gain range will be different, though. The main reason for differentiating between line and mic in this type of interface is to allow for different impedances and the ability to apply phantom power.

Auto-Sens would not be possible unless there was some kind of gain control element.

Where preamps tend to fall apart is at higher gains. For example, one of the advantages of a high-class preamp is really low noise performance at high gains, like if you have it cranked up to +70dB for a ribbon mic. In this case, turning up the high-class preamp to +70dB and feeding into an interface preamp running at 0dB gain will give superior performance (assuming the high-class preamp design is indeed superior) compared to turning up the interface preamp to +70dB.

Well, without a doubt, turning up the Octopus preamp toward very loud, a noise from the system becomes audible (it must be up quite high before you hear it).

Now for my situation, I do have VERY expensive pre-amps in my signal chain that have a unique coloration that is very desirable. I am duplicating the audio signal path of a specific studio (I know, the air is different because I am not in the same space) for a specific album... So, I definitely want to bypass anything that is not original to the signal path in my audio path.

The evaluation from Craig was one of the major factors for my purchasing the octopus assuming I could bypass the pre-amps of the unit.

So, I am not complaining rather just sharing some info I have found and I do think that the Octopus is an excellent for its features/cost ratio.  It just doesn't fit my bill and I am going to have to purchase another unit that fits my needs.

Jim

PS - my preamps are from the HELIOS mic/pre EQ units. If you know HELIOS you will understand my desire to bypass the OCTO pre's

I noted before that I use Grace One's for my mics and just shut the Octa-Capture preamps off. I have definitely not noticed any issues doing that. I just don't see why you would have to return it because you cannot totally bypass the pre-amp. I think you would be hard pressed to find any detectable effect with the pre-amp off.

Ken

jkleban, just leave the pres at zero and perform a null test before you start an octarant about features that don't work for you. If you were really trying to duplicate a studio's chain, why did you go "cheap" on the interface? Spend the extra cash on mics and monitors. The octacapture is just as transparent as my apogee...modern technology allows us to focus on other parts of the signal chain now. Caveat- I use the octacapture.

JBells...

You are right, perhaps I shouldn't have purchased the OCTA but that's water under the bridge at this point.  However, the ultra low latency and the thought of bypassing the pre's and just using the OCTA as a bank of A/Ds misled me to this purchase.

There are some good suggestions here about turning the gain down on the internal pre's and testing (which I will do).  The logic of this thread started with can you bypass the per's... some said yes, some said they didn't know... 

So, after also reading the manual which didn't confirm nor deny this information, I contacted ROLAND and got the posted response that I wished to share with those following the thread.

So, this isn't a BASH the OCTA thread just sharing some info.

Jim

jkleban


JBells...

You are right, perhaps I shouldn't have purchased the OCTA but that's water under the bridge at this point.  However, the ultra low latency and the thought of bypassing the pre's and just using the OCTA as a bank of A/Ds misled me to this purchase.

There are some good suggestions here about turning the gain down on the internal pre's and testing (which I will do).  The logic of this thread started with can you bypass the per's... some said yes, some said they didn't know... 

So, after also reading the manual which didn't confirm nor deny this information, I contacted ROLAND and got the posted response that I wished to share with those following the thread.

So, this isn't a BASH the OCTA thread just sharing some info.

Jim

Information is always good :)  If you want to see the specs, check out my pro review of the Octa-Capture on Harmony Central. These specs include ALL factors of everything in the signal path, including mic pres, output stages, etc. I forget the exact gain settings but I do all these tests with relatively high gains just to be mean .
 
As you'll see, noise is worst case below -110dB A-weighted, and averaging under -120dB. The only thing anomalous about the specs is that the second harmonic distortion product is at about -70dB. This appears to be a conscious tradeoff, as compared to several other interfaces I've tested, the Octa-Capture's distortion components above the second harmonic are extremely low. It's worth noting that many people have commented on the "sound" (or lack thereof) of the Octa-Capture preamps, and as any guitar player will tell you, second harmonic distortion is what "warms up" a sound. I'll let other people argue about whether anything happening at -70dB is significant!
 
Now, in your case, what I would suggest is getting a high-quality converter to take your preamp outs and convert into SPDIF. The Octa-Capture handles SPDIF so you could use two preamps simultaneously and bypass ALL of the Octa-Capture's analog electronics. This would also give you an opportunity to get really high-quality converters to match the preamps, and those converters will serve you well whatever interface you use in the future.
 
Finally, there are some very compelling Octa-Capture features that might mitigate whatever sonic advantages you might be able to obtain with a different interface that has bypassable preamps (although as Jim Roseberry and I both pointed out, good luck finding one): The drivers are excellent, you can aggregate units as well as aggregate with the V-Studio 700, the mic preamps are really pretty sweet, and the auto-sense feature (although of course it doesn't apply to SPDIF) is a real time-saver.
 
If I were you I'd keep the Octa-Capture and get top-of-the-line converters to send your preamps into the SPDIF I/O, then record the SPDIF input within Sonar. That way the last time you see analog is at your preamp out, and you don't see it again until it comes out of Sonar's master bus.

When you see the prices, you might decide just to turn the Octa-Capture preamps to unity gain!  Caveat: I haven't used any of the following, but assume they do what they say they do...

Probably your best bet would be the RME ADI-2, which is around $800 for two channels.

Another option would be something like the Benchmark ADC1 USB converter ($1,800) which converts analog ins directly to USB which you can use as an input in Sonar. Something like the Drawmer A2/D2 Dual Output A/D Converter will run you about $1,725.

I think the reason why premium converters are so expensive is because even "budget" converters are really good these days...A/D conversion is a pretty mature technology. Therefore, to get to "the next level," it's very expensive.

Anderton

jkleban


JBells...

You are right, perhaps I shouldn't have purchased the OCTA but that's water under the bridge at this point.  However, the ultra low latency and the thought of bypassing the pre's and just using the OCTA as a bank of A/Ds misled me to this purchase.

There are some good suggestions here about turning the gain down on the internal pre's and testing (which I will do).  The logic of this thread started with can you bypass the per's... some said yes, some said they didn't know... 

So, after also reading the manual which didn't confirm nor deny this information, I contacted ROLAND and got the posted response that I wished to share with those following the thread.

So, this isn't a BASH the OCTA thread just sharing some info.

Jim

Information is always good :)  If you want to see the specs, check out my pro review of the Octa-Capture on Harmony Central. These specs include ALL factors of everything in the signal path, including mic pres, output stages, etc. I forget the exact gain settings but I do all these tests with relatively high gains just to be mean .
 
As you'll see, noise is worst case below -110dB A-weighted, and averaging under -120dB. The only thing anomalous about the specs is that the second harmonic distortion product is at about -70dB. This appears to be a conscious tradeoff, as compared to several other interfaces I've tested, the Octa-Capture's distortion components above the second harmonic are extremely low. It's worth noting that many people have commented on the "sound" (or lack thereof) of the Octa-Capture preamps, and as any guitar player will tell you, second harmonic distortion is what "warms up" a sound. I'll let other people argue about whether anything happening at -70dB is significant!
 
Now, in your case, what I would suggest is getting a high-quality converter to take your preamp outs and convert into SPDIF. The Octa-Capture handles SPDIF so you could use two preamps simultaneously and bypass ALL of the Octa-Capture's analog electronics. This would also give you an opportunity to get really high-quality converters to match the preamps, and those converters will serve you well whatever interface you use in the future.
 
Finally, there are some very compelling Octa-Capture features that might mitigate whatever sonic advantages you might be able to obtain with a different interface that has bypassable preamps (although as Jim Roseberry and I both pointed out, good luck finding one): The drivers are excellent, you can aggregate units as well as aggregate with the V-Studio 700, the mic preamps are really pretty sweet, and the auto-sense feature (although of course it doesn't apply to SPDIF) is a real time-saver.
 
If I were you I'd keep the Octa-Capture and get top-of-the-line converters to send your preamps into the SPDIF I/O, then record the SPDIF input within Sonar. That way the last time you see analog is at your preamp out, and you don't see it again until it comes out of Sonar's master bus.

One thing to clarify among these points is that if you use your SPDIF ports to bypass your preamps then you cannot then expand your OctaCapture to use it with another unit or the V700. It needs the SPDIF port to do that.


Ken