World-Designs-Forum  

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

WD Amplifiers For discusson of World Designs Amplifiers

Reply
 
Thread Tools Display Modes
  #1  
Old 1st September 2006, 09:00 PM
Andrew Andrew is offline
Senior Member
 
Join Date: Dec 2005
Location: Korvatunturi
Posts: 932
Default Pre Amps?

Hi Peter,

Would you be willing to share some of your thoughts/plans on the pre-amp front?

Why am I asking? Well I know we had all those polls etc, all well and good, but things have gone quiet. Now last night I picked up my Hi Fi World for a read and my attention was drawn by your WD88VA article and your use of the DC relays for switching the inputs. I like it! Very much!

Will you be offering this option for your pre? I assume you're doing one. And, will you be doing something like the old PASII where we could buy a kit (case, plugware, knobs etc) and we had to supply our own attenuator? I realize an active will probably be your first port of call, but it would seem prudent, to me, to offer a passive style based upon the same internals, would it not?

My motive is simple, I have a set of S&B TVCs looking for a stylish home. I like the relay idea and a ready made case Series II style case would be ideal (even if I need to fit the TVCs myself, assuming they could be made to fit). I'm certainly not expecting you to change your plans for me, but if our plans coincide I would happily wait for the WD offering.

Please whet our appetites some more....

all the best,

-- Andrew
Reply With Quote
  #2  
Old 1st September 2006, 09:39 PM
Lord.
Guest
 
Posts: n/a
Default Re: Pre Amps?

I'd be interested in a Relay switching option to fit into my PAS-II.

I must get the new HFW and read that article, is it September already?
Reply With Quote
  #3  
Old 1st September 2006, 11:05 PM
Andrew Andrew is offline
Senior Member
 
Join Date: Dec 2005
Location: Korvatunturi
Posts: 932
Default Re: Pre Amps?

Quote:
Originally Posted by Lord.
I'd be interested in a Relay switching option to fit into my PAS-II.

I must get the new HFW and read that article, is it September already?
According to HFW it appears we're already in October.......now why do they do that..?

cheers,

-- Andrew
Reply With Quote
  #4  
Old 2nd September 2006, 09:17 AM
petercom's Avatar
petercom petercom is offline
Senior Member
 
Join Date: Dec 2005
Location: Shenzhen, China
Posts: 1,256
Default Re: Pre Amps?

Oh the stupidity of the publishing world. All monthly magazines, except topical, news ones, have a cover date a month advanced. The concept is that the buyer will look and see that it must be the latest one come out early! Also it can stay on the newsagents shelves until mid October when the next one comes out. As they all do it HFW has to fall in line - some hi-fi mags come out two months 'early'!

Back to the Pre. We will use relay switching on the new WD Pre3 as it seems a sensible way of switching straight off the input phono sockets. Unfortunately, due to the phono socket layout, I couldn't find a way of making it retro-fitable to the old Pre2, but you may be able to use it in other integrated WAD amps.

At present, due to the valves we are planning to use, we are going to have to stretch the cases vertically, or have the valve tops poking out the top (if anyone has views on this let me know as we are designing the case now).

We are also working on a passive version that could be quite novel if the plans work out in terms of advanced sonic performance, or it could be quite or'nery if they don't (sorry, can't explain until we've finalised the prototype).

I think it is fair to say that I am not a fan of cathode follower, particularly in a preamp output where the load dependance can be a factor. I know it has solved the occasional hum pickup problem in the pre2, but you won't be seeing it in a WD Pre3! Neither will we have the hum pickup problem as the output stage and transformer are going to be far more advanced in conception and performance. And we are also re-designing the moving coil step up transformers for incredible performance from low output mc cartridges.

I'll check to see if the TVCs fit the new case and report back.
Reply With Quote
  #5  
Old 2nd September 2006, 09:48 AM
Andrew Andrew is offline
Senior Member
 
Join Date: Dec 2005
Location: Korvatunturi
Posts: 932
Default Re: Pre Amps?

Hi Peter,

Sounds great! I'll wait and see the new Series 3 before I remove my TVC's from the plank of wood to which they are currently attached.

I would personally prefer to see the valves on a PRE to be inside the case as per Series II. I think this gives better WAF, is safer etc. Obviously, this is less viable on a power amp, which also has to accomodate large valves and bigger TXs.

As I said it would be ideal if the TVCs would fit, even if extra metal working is required. Clive M got some TVC's inside a Series II case, just.

Looking forward.

all the best,

-- Andrew

Last edited by Andrew; 2nd September 2006 at 10:26 AM.
Reply With Quote
  #6  
Old 2nd September 2006, 11:38 AM
david counter's Avatar
david counter david counter is offline
Senior Member
 
Join Date: Dec 2005
Location: south west London
Posts: 1,505
Default Re: Pre Amps?

Hi Peter,
I quite like the idea of having valves showing through the top of a case, I think it looks funky, luckely my Wife is happy with such things, breadboards ect. don't seem to worry her,
__________________
David
"I always wanted to procrastinate, but I just never got around to it."






Reply With Quote
  #7  
Old 2nd September 2006, 12:08 PM
Lord.
Guest
 
Posts: n/a
Default Re: Pre Amps?

Peter,

Could the new WD relay switching PCB be fitted, for example, into the (almost entirely empty) PAS-II chassis using short flying leads to connect the sockets to the PCB - or would this defeat the object?
I assume it is attached to the WD88VA selector switch using similar leads? It would finally give me a chance to use PSU-II's PRE-II output (well the heater voltages anyway!)
Reply With Quote
  #8  
Old 2nd September 2006, 01:37 PM
petercom's Avatar
petercom petercom is offline
Senior Member
 
Join Date: Dec 2005
Location: Shenzhen, China
Posts: 1,256
Default Re: Pre Amps?

I'll have a look. It wouldn't necessarily defeat the object as it moves all the switching to the back plane. The front selector switch then only has to switch the heater voltage to the relays.

Alternatively, if there is enough interest, I'll design a PCB to suit the Pre2. I'll add this as a poll, so don't reply here.
Reply With Quote
  #9  
Old 2nd September 2006, 04:12 PM
MartinJones's Avatar
MartinJones MartinJones is offline
Member
 
Join Date: Dec 2005
Location: Swansea
Posts: 73
Default MC step up

Peter,

" And we are also re-designing the moving coil step up transformers for incredible performance from low output mc cartridges."

....would these be suitable for the current (WAD) Phono? As foolishly I didn't buy them at the time.

Regards,
Martin
Reply With Quote
  #10  
Old 2nd September 2006, 04:32 PM
funk hunter funk hunter is offline
Junior Member
 
Join Date: Apr 2006
Posts: 9
Default Re: Pre Amps?

Hi Peter,
having tried to buy a PRE/PSU/PHONOII last year, I`m in the market for your III version. Would prefer the same modular design as the WADII, which looked a very smart but practical design. Can`t wait.
Cheers Francis.
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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Maplin Millennium 4-20 amps ? Swithers Amplifiers 6 15th November 2008 06:19 AM
eBay Chinese Valve amps? kt66se General 31 25th October 2006 03:52 PM
Current loops in valve amps acorn General 8 7th June 2006 09:21 PM
Blocking on valve amps acorn General 4 30th May 2006 11:59 AM
211 Amps acorn WAD General 5 10th January 2006 06:35 PM


All times are GMT +1. The time now is 11:44 AM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright World Designs