Member
- Posts: 390
- Joined: Tue Jun 19, 2007 6:23 pm
- Location: Calne, Wiltshire, UK
Has anybody had poor performance with the RME Fireface UC?
I've been spending the past few days upgrading my Hauptwerk system. Previously I was experiencing distortion which was most noticeable with Baroque-type sample sets (Freiberg, Velosovo, Zwolle, Kszrezcow - this one being particularly revealing) playing with full chorus. Adding mixtures makes the sound distinctly fuzzy, but I could hear it with 2' as well.
I thought the problem was that I was getting intermodulation distortion from not having enough speakers, and I have been spending the last few days adding more channels. I now have two pairs of Behringer Truth B3031A's, four pairs of B2031A's and a pair of Spirit by Soundcraft 4P's, which I use for the rear channel. Everything else is distributed between the Behringers, either with a stereo channel for each type of stop (foundations, upperwork, mixtures, reeds etc.) or else using using Hauptwerk's cycling algorithm to send everything to six stereo Behringer channels (the B2031A's and B3031A's sound very similar - more so than two speakers of the same model in slightly different parts of the room). I was previously using an RME Fireface UC as my audio interface, which gives 6 balanced output channels plus a "headphone" mix-down which I send to the subwoofer (SVS PC2000), and I have added a Behringer ADA 8200 digital-analogue converter to access the additional 8 ADAT channels.
While the new set-up clearly sounds a bit better than the old one, it hasn't really solved the problem.
While I was messing around with everything I realised that I could connect the digital output of one of my Sonos units to the SPDIF input of the Fireface UC. This was so that I could listen to the radio in the music room while waiting for samplesets to load etc., but I was struck by how bad the sound was compared to my HiFi (Sonos played through a Cambridge Audio amp and bit Tannoy speakers). Of course this cost ten times as much as a pair of Behringer monitors, but even compared to the Sonos speaker in the kitchen and the TV soundbar there was enough distortion that it was quite fatiguing to listen to.
So next I removed the Fireface UC from the organ and connected it up to the HiFi in the living room. The digital output from the Sonos unit went into the SPDIF input of the Fireface UC, and two of the analogue outputs from the Fireface UC went into the balanced XLR inputs of my Cambridge Audio amplifier. The analogue output of the Sonos unit went into an analogue input of the amplifier. After adjusting the level of the Fireface UC I could play the same music through the Sonos and switch between the two, effectively switching between the internal DAC of the Sonos unit and the DAC (and associated circuitry) of the Fireface UC.
Compared to the very clean sound of the HiFi, there was slight but noticeable distortion when listening to David Goode playing Bach on the Silbermann organ at Freiberg. With speech (BBC Radio 4) there was a little sibiliance with the Sonos DAC, but with the Fireface DAC the sibilance was quite marked, and very intrusive (I think speech is a good test of HiFi since we are all intimately familiar with it). I then tried a test recording of a sine wave sweeping upwards from below to above the limits of hearing. With the Sonos DAC I heard the expected rising tone. Playing the same track through the Fireface there were lots of other tones coming in and out at the higher end of the sweep. I am not a sound engineer, but clearly this shouldn't be there and I suppose it represents significant harmonic distortion (the test disc came with my in-car HiFi, and with that the sine sweep also sounds clean.
Now the Fireface UC is supposed to be a high-quality audio interface specifically recommended for use with Hauptwerk, so either it isn't as good as I had believed when I got it, or there is something wrong with my particular unit. Unfortunately it is a couple of years old and probably out of warranty now. I don't know if there is anybody who can test or repair it (I am in Southern England) or whether I should replace it, and if so with another Fireface or something else. I can't think of a solution which isn't expensive...
I've been spending the past few days upgrading my Hauptwerk system. Previously I was experiencing distortion which was most noticeable with Baroque-type sample sets (Freiberg, Velosovo, Zwolle, Kszrezcow - this one being particularly revealing) playing with full chorus. Adding mixtures makes the sound distinctly fuzzy, but I could hear it with 2' as well.
I thought the problem was that I was getting intermodulation distortion from not having enough speakers, and I have been spending the last few days adding more channels. I now have two pairs of Behringer Truth B3031A's, four pairs of B2031A's and a pair of Spirit by Soundcraft 4P's, which I use for the rear channel. Everything else is distributed between the Behringers, either with a stereo channel for each type of stop (foundations, upperwork, mixtures, reeds etc.) or else using using Hauptwerk's cycling algorithm to send everything to six stereo Behringer channels (the B2031A's and B3031A's sound very similar - more so than two speakers of the same model in slightly different parts of the room). I was previously using an RME Fireface UC as my audio interface, which gives 6 balanced output channels plus a "headphone" mix-down which I send to the subwoofer (SVS PC2000), and I have added a Behringer ADA 8200 digital-analogue converter to access the additional 8 ADAT channels.
While the new set-up clearly sounds a bit better than the old one, it hasn't really solved the problem.
While I was messing around with everything I realised that I could connect the digital output of one of my Sonos units to the SPDIF input of the Fireface UC. This was so that I could listen to the radio in the music room while waiting for samplesets to load etc., but I was struck by how bad the sound was compared to my HiFi (Sonos played through a Cambridge Audio amp and bit Tannoy speakers). Of course this cost ten times as much as a pair of Behringer monitors, but even compared to the Sonos speaker in the kitchen and the TV soundbar there was enough distortion that it was quite fatiguing to listen to.
So next I removed the Fireface UC from the organ and connected it up to the HiFi in the living room. The digital output from the Sonos unit went into the SPDIF input of the Fireface UC, and two of the analogue outputs from the Fireface UC went into the balanced XLR inputs of my Cambridge Audio amplifier. The analogue output of the Sonos unit went into an analogue input of the amplifier. After adjusting the level of the Fireface UC I could play the same music through the Sonos and switch between the two, effectively switching between the internal DAC of the Sonos unit and the DAC (and associated circuitry) of the Fireface UC.
Compared to the very clean sound of the HiFi, there was slight but noticeable distortion when listening to David Goode playing Bach on the Silbermann organ at Freiberg. With speech (BBC Radio 4) there was a little sibiliance with the Sonos DAC, but with the Fireface DAC the sibilance was quite marked, and very intrusive (I think speech is a good test of HiFi since we are all intimately familiar with it). I then tried a test recording of a sine wave sweeping upwards from below to above the limits of hearing. With the Sonos DAC I heard the expected rising tone. Playing the same track through the Fireface there were lots of other tones coming in and out at the higher end of the sweep. I am not a sound engineer, but clearly this shouldn't be there and I suppose it represents significant harmonic distortion (the test disc came with my in-car HiFi, and with that the sine sweep also sounds clean.
Now the Fireface UC is supposed to be a high-quality audio interface specifically recommended for use with Hauptwerk, so either it isn't as good as I had believed when I got it, or there is something wrong with my particular unit. Unfortunately it is a couple of years old and probably out of warranty now. I don't know if there is anybody who can test or repair it (I am in Southern England) or whether I should replace it, and if so with another Fireface or something else. I can't think of a solution which isn't expensive...