PLEASE REMOVE

[Skezza]

Hi

I have a number of active basses. In my signature you can see a warmoth jazz with nordstrand pickups and an audere preamp. It is silent as a mouse with my amp maxed and the treble and bass boosted. I have a number of bass collection bases that are also silent. But I have one that is noisy continual background hiss which only goes when you back off the treble on the guitar or amp.

Is a repair possible if not I would like to have a new preamp fitted. I may change the pickups as well what do you recommend and who would you recommend doing the work I am in Stone Staffordshire

skez

Edited March 1, 2012 by Skezza

[steve-soar]

Bass, pups, pre?

[gjones]

Is it screened?

Edited January 24, 2012 by gjones

[Skezza]

Its a 5 string bass collection P and J pickups but they are both HBs

not sure about the screening as the cavity has bee sprayed with some gloop. Im not sure its an Earth hum


skez

[BassBod]

Look for an internal gain adjuster - some preamps have them, and if set very low the usual background hiss can be a problem....but turning the gain (i.e. signal) up higher can help a lot.

Probably worth taking a photo of the preamp. There are some very good electronics guys on the forum who could help you decide if its worth repairing/modding or replacing?

[Skezza]

Thanks Bassbod I have gone over it witha magnyfying glass and a torch looking for any trimpots which some of my other bass collections do have, I found a little 2 position slide switch which does not seem to alter the sound at all in either position.

Ill do some phots 2mo and see if anyone has any suggestions. I would think the preamp is turned up as its a loud guitar for a nine volt

skez

[pete.young]

Is that the red one?

I put an Artec 3-band in my 465 and that seems to work pretty well. It was a big improvement on the original. You need to open out the holes for the stacked pots, other than that fitting it is pretty straight forward, keep the original Jack.

[Skezza]

Yes it is I part exed it for a prose karuna 4 string a while ago. Its my number 1 bass I love the sound and feel of it.

Did I buy it off you I cannot remember who I had it off

skez

[pete.young]

Yes, that was me. Don't remember it being noisy, but then my ears are probably not what they used to be!

[Skezza]

[attachment=98338:DSCF0034.JPG][attachment=98339:DSCF0035.JPG][attachment=98340:DSCF0037.JPG][attachment=98341:DSCF0036.JPG]



Noisy is relative as I said I have a warmoth jazz with an audere pre which is silent. My other bass collection 5 string which is a jazz style is silent despite having real single coils.

This is a very faint hiss which can be removed by backing the treble off the guitar pre amp just a little. It is not noticeable at any situation other that when Im practising on my own with my Markbass.

It does not come through the DI on the markbass and its not present with all my amps in fact this guitar is silent through my EA IAmps 500. Its probably me fussing too much. I like this guitar so much I was thinking of have an audere preamp and Nordstrands put in it like I have on my 4 string. Since having this guitar I have done every gig and every rehersal with it.

Anyway thanks for contacting if its ok Ill put your name in my feedback. Im going to upload some phots of the preamp for the techies to look at.

The photo with the finger on shows a tiny little slide switch which does slide but seems to do absolutely nothing to the sound. I have had this guitar for less than a year so I do not know if the preamp is the original one. I have 4 active Bass Collection basses the machine heads and bridges are all identical BUT the preamps are all different they do not even look similar and of cours as I bought them all off ebay I have no idea if any of the preamps are the original fittings as non of them has anything printed on it

thanks for looking at this

skez

Edited January 28, 2012 by Skezza

[BILL POSTERS]

Probably just a noisy semiconductor, try heating the PCB with a hairdrier while you listen to the hiss, see if it gets louder. Google the numbers on the chips, and if theyre plug in ones or if your solering skills up to it, replace em, probably only cost pennies if theyre generic types.

[Skezza]

Will try at the weekend
skez

[Skezza]

Tried the hairdryer it did not seem to alter the slight hiss. The funny thing is this guitar is silent in my Tmax, my Trace AH 250 and in the swr combo I have. Its only in the mark bass head and combo where it makes a slight hiss.

WHICH leads me to:

I borrowed and older 4 string jazz bass passive reissue with genuine single coils. That hummed slightly if you only had one pickup on when I tried it in my tmax, my TE and my swr combo
BUT when I put it through the markbass cmd102p it was silent with only one pickup on.

Im now more confused than when I started

skez

[BILL POSTERS]

Heating them up is only conclusive if it makes the noise worse, or less often makes it go away. I'd still be inclined to swap the chips if theyre generic numbers and not surface mount anyway.