World-Designs-Forum  

Go Back   World-Designs-Forum > World Designs > Problems
Register FAQ Members List Calendar Gallery Today's Posts Search Today's Posts Mark Forums Read

Problems For questions and answers re World Designs Projects

Reply
 
Thread Tools Display Modes
  #1  
Old 3rd October 2011, 10:39 AM
KC Jones KC Jones is offline
Member
 
Join Date: Jun 2008
Location: Stafford
Posts: 45
Default WD PRE3 problems, assistance needed.

Morning all

Its been ages since I last made a post, not that I have made many, but I was wondering if anyone could help me with my WD PRE3? Hereís the problem

I built the WD PRE3 (balanced XL version and PSU3) about 2 years ago, but until recently have not used it. Up until now I have been running my CD player direct into the WAD 6550 KAT power amp. The WAD power amp was bought 12 months ago and had been modified to within an inch of its life. Amongst other internal upgrades it contains a single input and volume control, all of which are working fine.

When I connect the PRE3 via output 1 (not the balanced output) to the 6550 input and the CD player to CD input on the PRE3, I get hardly any sound, Itís like the sound is not amplified, just like listening to a record without a phono stage.

I can adjust both volume controls and the sound slightly increases. I can switch the input selector on the front of the PRE3 and the sound is there on all channels. I can also swap the cables into the AUX input and again the sound is there on most channels. Swapping the cables from red to white inputs makes no difference, the un-amplified sound is still there.

After building the PRE3, all the values were checked in accordance with the build instructions and all were correct. The roundels have been soldered in place and all wiring was checked. I must also add my skill level is limited within electronics and can only follow the build instructions (obviously incorrectly !!) and solder.

Any ideas?
Many thanks in advance for your advice
Kevin.
Reply With Quote
  #2  
Old 3rd October 2011, 01:04 PM
bob orbell bob orbell is offline
Senior Member
 
Join Date: Nov 2009
Location: kettering northants.
Posts: 1,575
Default Re: WD PRE3 problems, assistance needed.

Hi KC,it sounds like you may have a short on the incoming signal, cheak with the PRE powered up, phono inputs to the earth post should read 50k, ie switch to phono and cheak phono input L&R switch to CD and cheak CD input L&R ETC. I take it that your 6550 still works directly conected to CD? and the problem is not in the 6550 volume control that you say you have fitted. BOB
Reply With Quote
  #3  
Old 3rd October 2011, 02:08 PM
KC Jones KC Jones is offline
Member
 
Join Date: Jun 2008
Location: Stafford
Posts: 45
Default Re: WD PRE3 problems, assistance needed.

Hello Bob,
Thanks for you reply.
Yes the 6550 input is working fine direct to CD, checked al the cables, they are ok too. It wasnt me who modified the 6550, that happened back down the purchase chain, I have no idea who did.

When I get in later I will check the inputs, but I dont know what setting to put the multi meter to and where to stick the probes to get some readings

Thanks - Kevin.
Reply With Quote
  #4  
Old 3rd October 2011, 04:04 PM
bob orbell bob orbell is offline
Senior Member
 
Join Date: Nov 2009
Location: kettering northants.
Posts: 1,575
Default Re: WD PRE3 problems, assistance needed.

Hi KC, set your meter to measure resistance (ohms) clip one end to the earth post (does not matter if it's red or black) the other to the center pin on phono L or R, with PRE switched on, and the selecter switch to phono, meter should read about 50k ohms, now switch selector switch to CD, meter should read zero ohms as should tuner aux tape, now remove meter probe from phono and insert in CD, set selector switch to CD, repeat test, CD should now read about 50k, on turning selector switch to phono tuner aux and tape meter should read zero ohms, do the same for all inputs. BOB
Reply With Quote
  #5  
Old 3rd October 2011, 10:22 PM
KC Jones KC Jones is offline
Member
 
Join Date: Jun 2008
Location: Stafford
Posts: 45
Default Re: WD PRE3 problems, assistance needed.

Hello Bob,

I have done the checks and the readings were zero on all pins except on the phono input, where I got 50.8k when the selector switch was on CD. This is the only reading. Thanks, KC
Reply With Quote
  #6  
Old 3rd October 2011, 11:04 PM
pre65's Avatar
pre65 pre65 is offline
Senior Member
 
Join Date: Jan 2006
Location: Ashen- Essex/Suffolk bord
Posts: 4,371
Default Re: WD PRE3 problems, assistance needed.

Quote:
Originally Posted by KC Jones View Post
Hello Bob,

I have done the checks and the readings were zero on all pins except on the phono input, where I got 50.8k when the selector switch was on CD. This is the only reading. Thanks, KC
So, have you tried plugging the CD into the Pre3 phono sockets and see if you get sound out with the selector on CD ?

They are all line inputs so it won't hurt.
__________________
Philip.

Everything in this post is my honest opinion based on what i thought I knew at that very moment in time.
Reply With Quote
  #7  
Old 4th October 2011, 05:08 PM
KC Jones KC Jones is offline
Member
 
Join Date: Jun 2008
Location: Stafford
Posts: 45
Default Re: WD PRE3 problems, assistance needed.

Hi Philip.
Thanks for the advice. I tried it this morning, but all I got was a loud buzzing sound with the music very faint in the background. The buzzing increases and fades when the volume is adjusted.

Just checked all the wiring and it seems ok. It looks like I may have to remove the solder from the roundels to remove that board and check behind it.

Thanks - Kevin.
Reply With Quote
  #8  
Old 4th October 2011, 05:23 PM
bob orbell bob orbell is offline
Senior Member
 
Join Date: Nov 2009
Location: kettering northants.
Posts: 1,575
Default Re: WD PRE3 problems, assistance needed.

Hi KC, just out of interest, can you hear the relay's clicking when turning the selector switch, with it powered. After trying Philips sugestion and getting buzzing sounds, you may have put the relay's in upside down, is this posible anybody. BOB
Reply With Quote
  #9  
Old 5th October 2011, 05:47 PM
KC Jones KC Jones is offline
Member
 
Join Date: Jun 2008
Location: Stafford
Posts: 45
Default Re: WD PRE3 problems, assistance needed.

Hi Bob
To be honest I'm not too sure if it clicks or not. I'm currently away at work until the weekend but when I get home I will check and report back.

Cheers - KC
Reply With Quote
  #10  
Old 8th October 2011, 10:49 PM
KC Jones KC Jones is offline
Member
 
Join Date: Jun 2008
Location: Stafford
Posts: 45
Default Re: WD PRE3 problems, assistance needed.

Hello Bob
Right I have checked the relays and they all click when selected, except there is no click when switching from tuner to aux and also the other way from aux to tuner. All others click ok.

Thanks KC.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 05:08 AM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Copyright World Designs