Anyone recording with XPR?

[carl170]

Hi.

I have an XPR which has a digitech gsp1101 in the effects loop. I have connected it up to my little Tascam digital recorder and it sounds good (if a little flat to my ears) and there is a slight background hum.

I have then tried hooking it up to my old Tascam Porta One and used a new chrome cassette to do a comparison. I get horrendous buzzing when using distortion (not much when clean). Annoyingly, the recorded sound on the old 4 track sounds bigger and better! However, the buzzing is awful! Would putting some sort of gate in help? Could it be a line level issue? The Porta one is using a mains powerpack and the digital recorder is just using batteries.

I am still rather surprised that the analog four track recording sounds better. I recorded a few snippets of audio on both formats and expected the digital to win hands down! Next, I am going to hook it up to pro-tools on my macbook and see how this sounds.

However, I would love to solve the buzzing issue and wonder what anybody else does?

Thanks in advance (as always!)

Carl

[rbc]

I'd check for loose connections to start. Try swapping out interconnecting cables and see if any of them have issues.

[RockmanCentralBob]

It's also possible that it just needs to be recapped.... those capacitors are easily 20 years old, double their normal lifespan.

[carl170]

OK, so I did a bit of wire jiggling tonight.

I plugged in the Voodu Valve and hooked that up to the tascam. Near Silent

I then tried the digitech GSP1101 hooked up to the tascam. Near Silent (horrible digital distortion though! )

I then plugged in the XPR into the power socket. It was not even switched on, but I immediatley noticed a slight hum from both the VV and GSP outputs that were hooked up to the tascam.

I switched the XPR on and hum and noise again! I noticed that the VV has no earth (2 prong USA plug into a 110>240 transformer). Also the Tascam is not the original powerpack, it is a random brand, and ends in a small adaptor, which I don't think is earthed.

So I took apart the UK plug (fitted last week as the original was a Europlug). I disconnected the earth, which might sound a bit mad but quite common for European plugs (The earth on a modern europlug goes around the edge of the europlug and as I was using a 2 prong adaptor Euroadaptor the earth had therefore never been connected ).

I then switched on again and the horrible buzz had disappeared!. Any thoughts? I know it cannot be good to disconnect the earth, as it is there for a safety reason

The XPR is still a noisy unit when a guitar is plugged in,fully distorted with volume up but not actually strumming strings , as are the 2 DG's I own. I tested it against my marshall amp and the marshall is actually noisier!

Now I noticed the GSP and VV both have noise gates (Hush in the VV case). So I think I can deduce that the buzz is an earth issue and the noisy unit is becasue there is no noise gate? Do I need a smart gate or similar in the loop?

Thanks for the input so far, it really is appreciated!

Also, I think I will try a recap on one of the DG's and then maybe tackle the XPR next winter. They are about the same age, so will be inertested to hear the difference. I may shoot some sound clips before and after.

Regards

Carl

[rbc]

It sounds like you might have a mixture of 110 and 230 gear. What's 110 and 230? If you have 230 power, what kind of 230/110 conversion do you have?

[carl170]

The XPR is 220\230 Volt
The GSP11011 is 230V
Tascam is running off a 240 to 13V powerpack
The Voodu Valve is running a 230-110V converter then a 110V to 12V Rocktron powerpack. Not really in the equation though, it was only for testing purposes.
Distortion Generator is running off a Rockman 240 to 12 Volt AC powerpack. Again, Not really in the equation though, it was only for testing purposes.

Regards

Carl

[rbc]

If you haven't yet, test the XPR by itself. Just the guitar, XPR using headphones with the XPR. Do you hear a hum then?

[Guitarvamp]

If you haven't yet, test the XPR by itself. Just the guitar, XPR using headphones with the XPR. Do you hear a hum then?

Yes. Do this. That will tell you if it's the XPR, or something else. It could be a cable, or likely a grounding issue.

Grounding/not grounding has been the cause for numerous recording nightmares. Electric transformers can also be noisy beasts.

[rbc]

I thought I'd add something to this. I have a Behringer Xenyx 502 mixer that has a two prong (ungrounded) AC adapter for power. The Rockman gear is grounded. I've found that when I don't have the signal ground connected between the Rockman gear and the Xenyx, I get a little hum. Extending the signal ground from the Rockman gear to the Xenyx makes the hum go away. In my case, lifting the ground leaves me with a hum.

Some caveats are that I'm in North America and have 120 volt mains. My setup also has very short cabling, so I don't have issues with distant grounds having slightly different potentials. It's easy for me to tie all the grounds together.

[carl170]

Sorry for the delay, but I have been busy the last few days.

I will try your suggestions and report back.

Regards

Carl