Jasmine LP-2.0MK II problem

[Soimmvt]

It seems that I have no lucky hand in buying second hand audio equipment. I recently bought a Jasmine LP 2.0 MKII phone preamp. As I understand this is a very good pre amp at a reasonable price. Unfortunately I’ve never come around in really testing it.

After I received the amp, I hooked it up and there was a terrible noise coming from it. The audio signal comes with a terrible (not a humm) electrical signal/sound. It is hard to describe, but I’ve recorded it.

I’ve changed the connections and even the turntable but the signal was still there. This signal comes in MM and MC mode and is in MM more quiet but still there. If I disconnect the TT the noise is gone. SO there is no noise if I don’t use the input of the Jasmine.

The seller claimed that he had no problems with it….

I gave it to my audio repairman and after looking into it, he also cannot find the problem. It is a mystery.

Any thoughts or experience out there?

 

[Mister Pig]

Just posting to rule this out. I don't know what you are using for amplification, but I have seen some people do this. They wire the outboard phono stage into a phono input on a pre amp/receiver/integrated amp, and they get an issue like you are describing. If the unit is working fine on the tech's bench, there must be a root cause in your system somewhere. I would be looking at a ground loop issue if the above problem is not present.

EDIT: Does your tech have the same problem on the bench? Or is it quiet there?

Regards
Mister Pig

 

[62sunbeam]

What input is it plugged into on your amp/receiver?

Not phono I hope. Try one of the other line level inputs.

If the sound persists try running a ground from the preamp to your amplifier. Also make sure all connections are well seated.

Good luck

Eric

 

[Duane]

I gave it to my audio repairman and after looking into it, he also cannot find the problem. It is a mystery.

Any thoughts or experience out there?

When you had your repairman look into it, did you bring the turntable with you and had him test the Jasmine with your table?

 

[Soimmvt]

Hello and thank you all for your quick responses. My tech has the same problem, so it can't be my setup. However grounding the Jasmine to the pre amp I did not try. I will inform my tech about this suggestion and get back.

Again thanks!

 

[Soimmvt]

Well I got it back yesterday. It turned out to be a bad solderjoint at the mc selectorswitch. The electrical sound is gone. I immediately changed the outputcaps with jantzen caps and hooked it up. In comparison with the yamaha c2x mc stage, it has slightly more authority in sound,a bit more open and more pronounced midrange. I wonder if this will improve during burn in. I also wonder if a better powercord will improve the performance.

I've noticed that the jasmine is very sensitive to the transformers of other audio equipment. It is slighly less noisy at full volume than the yamaha and its output is higher.

 

[revox-b77]

Glad you have it sorted out.