Issues in recording FanX thru Presonus interface

[sishan]

Hi,
I'm recording "audio" using Presonus FireStudio Mobile on my Macbook Pro and Roland Fantom X8 keyboard. I'm connected by balanced TRS cables from Fantom to balanced line inputs on the back of FSM and from FSM to MBP, I'm using firewire. Using Garageband as DAW.

My issue is that piano, organ, strings (virtually every sound, not just these) sounds have changed drastically towards worse. The sound is more metallic, mid-tones are high, lacks fullness, warmth, becomes thin and non-real. I'm using headphones and they sound much better and more real when I play directly from my keyboard thru headphones i.e. without FSM. But once I hook up thru FSM, the sound got changed when monitored via either headphones or studio monitors.

Any idea anyone or similar experience?

Thanks a lot
Shan

[Romey]

Sounds loke you may be double triggering the fantom. Once when you hit the keys and another when the note returns from the pc. You might try turning local off on the fantom or turning off midi thru on the PC if this is the case.

[sishan]

This is not MIDI, I'm talking audio here. Essentially what I hear is thinner and less richer. So can there be a chance of double sound?

Thanks

[rcraven]

If you play a note and have Midi coming out of the Fantom and looping back in, the Fantom will play 2 notes instead of one and they start nearly at the same time.
These 2 notes with the same patch, same pitch and with the small delay will cause the sound to become thinner.
The problem is usually called phase cancellation (look it up on Google).
So it could quite easily be a midi feedback problem.

Unplug you midi out cable from the Fantom and see if the sound changes.
If it does then that is the likely culprit.

All the best

Royce Craven

[sishan]

Thanks for your reply Royce. I understand what you re saying but this is not the same case. My MIDI USB is not plugged in at all. It's just my FanX connected to the interface thru balanced cables and ports. The interface is connected to MBPro via firewire for bus power and my headphone from the interface headphone out. That's all about the connections. :-)

If you have a Fantom, essentially the ultimate grand patch sounds bright and punchy, thinner piano, very similar to PR-F003 Bright Tune. The warmth and sweetness of the tone is replaced by harsh punch.

So basically the same patch when coming out directly from fantom headphone out (without the interface) and via the interface headphone out are drastically different.

Anything else to check anywhere? I have also posted it in the Presonus forum but yet to hear from anyone.

Note: btw, my balanced cables are 4m (13feet) long. Can that be an issue with signal loss / degradation?
Thanks
Shan

[rcraven]

I see, your FanX is just connected with audio cables to the Audio Interface and the Audio interface is connected to your Mac. You are comparing the FanX headphone output to the Presonus headphone output.

I see that the Presonus has a power plug at the back.
Power it up without the Mac and try the headphones so we can rule the Mac out.

A professional balanced cable system can run 200 meters without problems.
The FanX is pretty good and I would assume the Presonus is also OK.

Cheaper systems can roll off the top a bit, but I don't think that is what you are hearing.

The FanX has the same audio feed coming out the main output and going into the headphones amp and if anything the headphone amp is usually a little noisier .
I assume you have the cables plugged into the left and right outputs A, right next to the headphone socket.

Capacitance in the cable can cause the highs to roll off. Are they reasonable cables? Have you got a mate that you can borrow a set from to check?

Try just sending a mono feed, a single cable from A Left output from the FanX
If this solves your problem ONE of the cables is likely to have been wired backward.
You can check with a meter - tip to tip, ring to ring and sleeve to sleeve is obviously correct, but you might have tip to ring and ring to tip even in a new cable.

If the cables are correct I would try another keyboard or mp3 player to see if it is the Fantom.

What is the impedance of your headphones. The Presonus is expecting 60ohms from the spec on the web.
I couldn't find the impedance for the FanX. Impedance mismatch can also cause differences in sound quality.


Try those few things and see if the picture is any clearer.

All the best
Royce

[Romey]

Is it possible you are still getting a doubled sound? Can you turn off direct monitoting in your audio interface? With direct monitoring on, You can also have a doubled sound, one from the fantom and a slightly delayed double from your audio interface when recording.

[sishan]

Royce, first of all, thank you very much for appreciating my trouble and taking time to write so much !! :-)

I see that the Presonus has a power plug at the back.
Power it up without the Mac and try the headphones so we can rule the Mac out.

hmmm, Presonus didn't include the power adaptor in the box as this unit can be bus powered. However, they can ship it free if ordered over phone but since I'm not based in the US, it's difficult to procure one. So, will have to manage a standard 12v 1amp power adaptor to try your suggestion. But tell me something...even if I get better results using the main, I'll have to connect it later with MBP anyway for recording. What will I do then in that case? :-)

I assume you have the cables plugged into the left and right outputs A, right next to the headphone socket.

Yes, I'm using these balanced ports A

Try just sending a mono feed, a single cable from A Left output from the FanX
If this solves your problem ONE of the cables is likely to have been wired backward.
You can check with a meter - tip to tip, ring to ring and sleeve to sleeve is obviously correct, but you might have tip to ring and ring to tip even in a new cable.

Haven't tried using single cable for a mono feed but I suspect it will yield the same result. Because, I checked the cables with a meter. T-T, R-R and S-S are all perfect. Cables are of high grade and I had them custom-made as this quality is not found on the shelf here.

If the cables are correct I would try another keyboard or mp3 player to see if it is the Fantom.

will check that but can this be a likelihood?

What is the impedance of your headphones. The Presonus is expecting 60ohms from the spec on the web.I couldn't find the impedance for the FanX. Impedance mismatch can also cause differences in sound quality.

checked that my headphone impedance (Roland RH-50) is 32ohm...do u really see this contributing to the problem?


Yes, will try out putting the main adaptor on and using mono feed and output from my iPad to Presonus and will let you know the result

Thank you

[sishan]

...Can you turn off direct monitoting in your audio interface? With direct monitoring on, You can also have a doubled sound, one from the fantom and a slightly delayed double from your audio interface when recording.

Romey, how do I turn off direct monitoring from the interface? Say when I'm monitoring thru headphones, my studio monitors are not connected from the main OUT of Presonus and the main vol is also turned all the way down to zero. Vice versa when I'm monitoring thru studio monitor, headphone jack is not connected with Presonus. btw, same results using monitors. So can you explain what you mean.

... slightly delayed double from your audio interface when recording.

I don't get this "from my audio Interface" part. Say, I'm not recording anything. Now I'm just connected my fanX with Presonus thru balanced cables and Presonus with MBP via firewire for bus power. That's it. No other connection or recording.

Thanks much

[Romey]

Sishan,
Generally speaking, Inputs to the audio interface will have a direct output that bypasses the audio converters and routes straight to the outs to provide zero latency when monitoring. The same input is routed thru the audio converters and then to the software to be recorded on a track and back out to the monitors as well. You end up with 2 sounds at the output, one delayed by the time it takes to go thru the computer and one direct. The interface has a mixer which you can turn down the direct sound.
However, this is usually only a problem during monitoring/recording and does not effect the recorded sound on playback.

[rcraven]

We start on the most common problems first, then the less likely ones.
You need to isolate the problem. Fanx, cables, Presonus, Mac or headphones
Cable and headphones are looking OK. Substituting other gear can isolate what is causing the problem.
If you can't remove the Mac from the picture then we have to treat the Presonus and Mac as one unit.

OK, how about checking the routing/mixing in the Presonus. The web shows that there is a mixer.
If the signals coming in are blended then this can cause similar problems.

Check that the Presonus inputs from the Fantom are panned hard left and hard right and that you are routing the signal to the headphones.

Royce

[Rodan]

From your description of the sound it seems like the Presonus might be filtering or clipping the signal. If you reduce the level from Fantom to the Presonus, is the sound still changed? That would rule out clipping in the Presonus ADC.

[sishan]

@Romey and Royce, understand what you are saying guys. Completely forgot the mixer/routing part. There is only a soft one called "Universal control" and will have to play around with that.

@Rodan, yes even if my input vol from the FanX is pretty low, I still get the problem.

Thanks guys...will let you know. If there may be confusions from the soft mixer controls, will come back bugging again with screen-shots :-)

[sishan]

I DID IT GUYS !!!!

After a lot of fiddling around the controls which I need to understand from you guys (stated below), when I panned the input channels 3-4 hard left and right (using headphone as output on the right of the screen), it did the trick. So, I guess signals were coming on top of each other and hard panning created the true stereo image, right?

Thank you very much guys for all the help. I really appreciate this.

Now, for some understanding...
1) In the second image, what do the ch 11, 12, 13 (daw1, 2 and 3) mean? Only ch1-10 are physically present on the interface.
2) In the first image, what does this text mean? "mix is bypassed. output main is assigned....". Does this mean that the fed audio signal is NOT routed via the ADC to the software DAW? In that case what is DAW return 1-2 where the main output is assigned?

Again, many thanks for your time :-)
Shan

[sishan]

After the initial success, I quickly created this. :-)

Let me know if you liked it...

thanks