Quad 34 Pre

[dantheman91]

Hello Guys

Well i was given one of these on the weekend but its not currently working hoping you can help...

Powers Up the inputs are very erratic going from one to the other i have read on DADA that its the PCB that has gone i would like to get it repaired i have spoken to my tech will be booked in for a quote soon...only 1 channel working on Aux , Radio distorted , :scratch:

Any thoughts?

[Firebottle]

More than likely it is the quad analogue switch chips, 4066 or similar number.

Had a similar scenario myself.

[Ammonite Audio]

The Quad 34 is lovely to look at and to use, but IME/IMO sounds poor even when freshly restored, so I recommend that you don't throw too much money at it. I know that some people will disagree and quote Peter Walker's well known marketing line about 'straight wire with gain' but the excellent Quad power amps were rather let down by preamps like the 34.

[walpurgis]

I agree. I've used them. OK as a back-up, but the sound is lacklustre. If it can be sorted economically, fair enough, especially if it was a freebie.

[dantheman91]

More than likely it is the quad analogue switch chips, 4066 or similar number.

Had a similar scenario myself.

Hi Alan

How are you? Do you have an idea of repair costs if this is the fault?

Thank you..

[dantheman91]

Thank Hugo...

[dantheman91]

I agree. I've used them. OK as a back-up, but the sound is lacklustre. If it can be sorted economically, fair enough, especially if it was a freebie.

I'm looking into it will be good as a back up not that i need it LOL.....Yes it was free....:)

[Firebottle]

Hi Dan I'm fine, you too I hope. The cost of the chips is very little, they are equivalent or similar to this
https://www.ebay.co.uk/itm/TEXAS-INSTRUMENTS-CD4066BE-IC-ANALOGUE-SWITCH-QUAD-14DIP/181883204122?epid=1693682695&hash=item2a5915721a:g:o~wAAOSw-W5UtpqI

Have a look on the board and see if you can see any chips with the number 4066 on them, I believe there are 4 from memory.

:)

[dantheman91]

Hi Dan I'm fine, you too I hope. The cost of the chips is very little, they are equivalent or similar to this
https://www.ebay.co.uk/itm/TEXAS-INSTRUMENTS-CD4066BE-IC-ANALOGUE-SWITCH-QUAD-14DIP/181883204122?epid=1693682695&hash=item2a5915721a:g:o~wAAOSw-W5UtpqI

Have a look on the board and see if you can see any chips with the number 4066 on them, I believe there are 4 from memory.

:)

Hi Alan

Im very good thank you , I will pass these onto my technician - i had a look and their are 4 in their...

Thank you...

[dantheman91]

Back up and running happy days..9 chips relaced aswell as a few caps Just running the 303 power amp and tannoys sounds good... Early def leppard playing high n dry from their early days...

[mikmas]

Back up and running happy days..9 chips relaced aswell as a few caps Just running the 303 power amp and tannoys sounds good...

Congrats on the successful repair!
I ran a 34 with my 303 for a good while - must say I thought it's lack of character a big plus point :lol:

[dantheman91]

Congrats on the successful repair!
I ran a 34 with my 303 for a good while - must say I thought it's lack of character a big plus point :lol:

Sounds fine to me mike....:)

[mikmas]

Sounds fine to me mike....:)

:)

Also fetch a decent price when moving on .. so win win really.


Edited to add:

Ken Rockwell does a great review of the 34 - and it's got graphs :lol:

https://kenrockwell.com/audio/quad/34-preamplifier.htm