The Ultimate 834 Phono Stage

[Jay]

OK Have bitten the bullet & ordered a full 834 kit with valves from Germany.

Questions:

1, Where can/should I get a transformer (toroidal or R type) & a choke,  ones that are good, suitable & cost effective.

2, I'de like to include a Good quality volume pot or stepped attenuator. any suggestions on what to get & where.

3, If good pot etc can be found where in the circuit should it go.

4, Would also like to be able to switch between input sockets.

5, SUTs any recommendations for decent cost effective ones.
    MCs I have, are AT OC109 Mk1  & Dennon 103r.

6, Also where in the circuit would they go.

7, Also good quality rotary switches for above.

8, Am planing an Aluminium 2 box set up, Should I line the boxes with copper foil?

9, What type of plugs/sockets should I use for the link between boxes.

 Links & pretty pics help loads LH s

[ZZMoko]

Jay have a read here http://www.lencoheaven.net/forum/index.php?topic=22195.0 I went through most of what you asking in the thread.

As to Rotary switches I experimented with a few and ended up with the one from HiFi Collective..for SUT's for a 103 the Beyerdynamic ones are fairly cheap and give a good sound but Altec 4722's made a big improvement but cost a lot more....Partridge ones come up fairly often and are meant to sound very good.

[Jay]

Hi David,
 I have nearly everything ordered except the Choke can't seem to find a source that works without exorbitant postage from the US.
Have looked into & now bought a pair of Partridge Sut's 

[ZZMoko]

Here you go http://www.bluebellaudio.com/

[Jay]

great, contacted bluebell

[ZZMoko]

As works starting to slow down I've finally got time to work on this project....

So my aim with this build is to produce a virtually silent phono stage with as close as possible to the RIAA curve for as good as it can get reproduction of my records.

To achieve this I'm going to use as closely matched components as possible and arrange the PCB layout inside the case for the shortest and least interference runs for the signals.....If I can I'm going to use valve rectification to supply the PCB from a separate PSU to again keep anything noisy away from the signal areas I've a choice of two transformers kindly given to me by Jay before he departed these shores...

So first question is that there seems to be two PCB suppliers for the 834 boards....any idea if there's much difference between the two of them...

http://www.ebay.co.uk/itm/201368372434?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

http://www.ebay.co.uk/itm/Douk-audio-United-Kingdom-MM-RIAA-Turntables-Phono-Pre-amplifier-DIY-KIT-/271867708056?hash=item3f4c940298:g:~dUAAOSwXeJXfPgT

I'm not sure if I would actually use much of the supplied kit.....is there just a PCB still from them?

So any ideas of how to proceed..recommendations for resistors / caps/ chokes etc to use all is welcomed..?

[Jay]

Just back from Belgium..... nice tidy country.

If i were you id find out if they supply the psu board as well

SUTs now arrived
 One has input of 21.1 & output of 247.5
 2nd has input of 20.7 & output of 237.6

would these be classed as a matched pair

[Jay]

David,
 Ive re-ordered the board with just resistors & caps as the full board was cancelled.
 Also getting Golden Dragon valves, which are all matched.

 Have you decided which resistors & Capacitors you are going to change.

[ZZMoko]

I haven't got any further with my plans as I've distracted myself with building an Utrasonic record cleaner and strangely I didn't get any answers to my queries regarding building a valve rectifier for the stage so I've sort of come to a halt on the ultimate phono build.

But my plan was to use these Kiwame resistors as they are very closely matched and sound nice in the Pre amp that I built http://www.hificollective.co.uk/components/kiwame.html and they are not too expensive.

As to capacitors I was thinking of these as they offer 1% matched pairs by request http://suppression-devices.com/ansar/ppa-audio-capacitors.html

For the power section I read these Panasonic caps are supposed to be good http://www.ebay.co.uk/itm/111020269027?_trksid=p2055119.m1438.l2649&var=410226786835&ssPageName=STRK%3AMEBIDX%3AIT

I hope that helps and good luck with build.

[Jay]

Great info David,
 My build will start over the X mass period IF the board arrives......
The winter is a busy time for me so things tend to get put off till the wether begins to improve.
 
 Good luck with the U/S cleaner 

[Chopsaw]

As works starting to slow down I've finally got time to work on this project....

So my aim with this build is to produce a virtually silent phono stage with as close as possible to the RIAA curve for as good as it can get reproduction of my records.

To achieve this I'm going to use as closely matched components as possible and arrange the PCB layout inside the case for the shortest and least interference runs for the signals.....If I can I'm going to use valve rectification to supply the PCB from a separate PSU to again keep anything noisy away from the signal areas I've a choice of two transformers kindly given to me by Jay before he departed these shores...

So first question is that there seems to be two PCB suppliers for the 834 boards....any idea if there's much difference between the two of them...

http://www.ebay.co.uk/itm/201368372434?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

http://www.ebay.co.uk/itm/Douk-audio-United-Kingdom-MM-RIAA-Turntables-Phono-Pre-amplifier-DIY-KIT-/271867708056?hash=item3f4c940298:g:~dUAAOSwXeJXfPgT

I'm not sure if I would actually use much of the supplied kit.....is there just a PCB still from them?

So any ideas of how to proceed..recommendations for resistors / caps/ chokes etc to use all is welcomed..?

I've built them using both boards and I prefer the first one you listed. When I built the last phono stage I used Kiwames right through including the power supply board and I'm more than happy with the result. However I used some tight spec metal films for the RIAA network. I can't remember why I did that but I'm building another after Christmas so maybe that will jog my memory. After trying some cheap eBay polys and various Russian Caps I settled with Ansars for the coupling caps. They give a nice clean sound and after much listening I'm going to replace the oils in my preamp and power with the same. One last thing, I can also recommend the Thorsten mods and you'll lose several components per channel too which can't be bad. The one mod I didn't do was to bypass the supply rail caps. I've tried it before without any conclusive results so I didn't bother.

[ZZMoko]

So I've finally started work on my two box 834 above is the new separate power section complete with new ultra fast diodes. At the moment I'm going to keep this fairly stock just to get everything up and running again.

[ZZMoko]

[url=http://i.imgur

Then with PaulFromCamdens help I've stripped out all the original RIAA section components before starting with the new upgrade parts.

So have I missed anything obvious so far, or is all this looking ok?

[spaceistheplace]

You can hold onto those small yellow 1uf caps (ERO 1813 I think?) and use them to bypass the 100uf Elna Silmic . might as well, better than in the waste bin.

Locations here, beneath board probably preferable if you have the room but either will do.




Also I see the other 2M is still there in the pic, just a reminder to not forget the 680k in that position.

Curious to know what you think of those Ansars! I hear their name come up a lot as a fantastic and inexpensive film, but not as great of a deal for those of us on this side of the pond i suppose.

[ZZMoko]

I've a question regarding caps on the underside of the PCB...with my case there is not a lot of height so I use short PCB amounts probably about 10mm in height now this would place any cap very close to the metal case and possibly touching it.

Would this be safe or should I just give up on the idea of underboard caps?