ACL 15 dl distortion when recording from vinyl or cassette

ulftho wrote on 2/19/2013, 11:28 AM

Using the PA005-2 USB preamp delivered with my ACL 15 deluxe ver 10.0 I get severe distortion when recording from vinyl or cassette source, mainly when sound signal reaches high levels. When recording from cassette deck, the PA005-2USB is fed on LINE IN with switch in INPUT LINE position, feeding it from speaker out jack of power amp, but with output level of power amp reduced. Checked that recording level indicator of Recording window does not exceed -10 dB AND with Level control on max. Also tried recording from vinyl via power amp LINE OUT into PA005-2USB LINE IN and switch LINE INPUT, same result. Also tried recording from vinyl turntable direct into PHONO IN of PA005-2USB and input switch at PHONO, same result.

Is this problem simply due to too small buffer of playback?

Using an ASUS laptop 1101HA, 1331 MHZ Intel x86 family 6, 1024 MB RAM, free usable size 119 MB when ACL running, Windows XP SP3, free disk space in excess of 10 GB, Sound card Realtek HD Audio.

Thanks,

ulftho

Comments

johnebaker wrote on 2/19/2013, 12:44 PM

Can you be more specific on the model of the laptop ie what is the model number on the label underneath? There are many different models of 1101HA.

If this is the laptop I think it is, it has only two audio sockets on the side one for headphones and the other for a microphone. Are the colour coded ie is one green and the other pink or red- or do they have symbols along side them?

If you are feeding the audio into a microphone input then quote . . . . My impression is that some part of the system is subjected to higher signal levels than it is capable to handle . . . is correct.

John

ulftho wrote on 2/19/2013, 2:30 PM

John, thanks,

I´m mentally blushing for not having made the obvious check to test an exported soundfile on a different computer, particularly as I have two other computers at my disposal. Testing a mp3-file on a Mac showed no distortion. So far I only had tested the recorded files via the built-in playback of the ACL. It seems that your "lateral thinking" already has worked. It could also be that posing the question and to be forced to put it into words triggered some creative thinking...

However, the laptop in question has two 3,5 mm jacks and I was using the earphone output to listen to the playback. The PA005-2USB that worked as go-between from source to computer was connected to a USB jack of the same computer. Sorry not to have stated that initially, but I thought it obvious on account of the "USB" end of the type designation.

I am now going to check other recorded files on a different computer and hope this Q&A anyway will be of some guidance to someone.

Thanks for your trouble,

ulf

johnebaker wrote on 2/19/2013, 4:59 PM

You are not the only one who is .

I missed the fact that the device was a USB converter - I presume it is the Hama PA-005?

According to the spec for the PA005 the device has a max input voltage of 38mV.

This does seem very low if it also refers to the line input! Most line inputs I have come across are in the range 350mV to 1 volt.

However maybe 2 x has got a result.

John

ulftho wrote on 2/20/2013, 3:18 AM

John,

The preamp PA-005-2 USB does not declare any other name than MAGIX. Serial or type no stated as 00011349. 38 mV certainly seems very low, but may refer to phono input. This preamp has two input jacks, one for phono [the earlier standard RCA coaxial type plug), the other for line (3,5 mm phono plug) and has also a switch labelled INPUT LINE/PHONO. The phono input, obviously intended for direct connection of gramophone pickup (needle) also has a switch labelled MM/MC, which I guess is intended for two different types of pickup, moving magnet and moving coil. As I remember it the documents included in the delivery did not specify the preamp to any higher extent, so if you have access to the complete spec - including max voltage for line input at a defined THD level of,say, 1 % - I would be grateful for it. Not being very apt at handling my fairly new Mac, I do not try to include any picture of the preamp, but if it would help I can include it in an email, if you tell me where to send it.

/Regards, Ulf