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91
Amplification (Pre/Power) / Re: How to Build a killer Amp
« Last post by stevenvalve on January 03, 2018, 05:08:49 PM »
The other wire in this amp is partly the wood coated yamamura. Its the same stuff as used in yamamura 5 interconnect, beware not all yamamura wire is brilliant. I also use 1930 to 1950s Hanley cloth covered solid core wire, Very good sounding wire. 
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Amplification (Pre/Power) / Re: How to Build a killer Amp
« Last post by stevenvalve on January 03, 2018, 05:00:23 PM »
Hi Steve.  Will the Dueland be happy at that voltage? those stacked copper foils do not have the greatest of reliability at anything over 100 or so volts.  I see the VSF DC copper caps have a 400v rating so maybe at UKP-165 each they should hold up.  Do you employ a delayed switch on for the B+ in your circuit?

The PC networking cable wiring you are using, what brand is it?  I bought 500m of the stuff, but it turns out what I thought was CAT6 cable was from china and recycled WW11 aircraft body parts coated in what appears to be darkly tarnished oxidized recycled copper...................bloody awful stuff, you can tell by just holding the stuff, proper copper has around 3 times the weight and is no where near as flexible.  Others be warned, go to the likes of Belden cables and avoid this SHeeeeeeeT.  Ozzy re sellers must make a packet on re selling it into our market.
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Will the Dueland be happy at that voltage, They are rated 400V but previous experience has shown he these caps are fragile regarding voltage. But still the voltage here is lower around 300 - 350v.
 My cat 5 is vintage solid core Belden cable for the filament wire. Jaycar has the newer Cat5 and it is made in china, looks OK, but does it sound good, it seems to sound OK. I always run a B+ switch, Love it.  The B+ switch is so important and has a huge effect on the sound, i have only found a few brands and types that really sound good, the big early vintage English ones are nice, they need to be cleaned out thoroughly, obviously go for brass or copper switches if you can find them. 
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Amplification (Pre/Power) / Re: What is the ultimite amplifier
« Last post by vitavoxdude on January 03, 2018, 12:38:58 PM »
An interesting point Tuyen raises regarding the older WE gear.  I agree with his comments generally in that for classical, jazz, opera that they do rule the roost reproduction wise but when more modern recordings are fed to them they do not fare quite as well.  Here I think they show up the modern recordings for being sub-optimal with all their eq and mastering downwards in the quality / emotional stakes.

When you take music and place it through soo many meat grinders what's left pales into insignificance in comparison to many of the old one take R2R recordings IMO.  This was all going on prior to opamps and low voltage power supplies and PIO caps and chokes.  So many would never have heard a great WE system to know how emotional they can portray music, quite unlike the processed pap and mastering that get's churned out by many these days.

So massive 90Kg solid state amps are good with inefficient IB speakers which need 100w to even get going but leave you questing after that magic something, whereas horns on 5 watts will fill a large room with SE valves driving them filling your soul. And yes I know OP transformers reduce the bandwidth.  Only the WE 555's throw half the baby out with the water (50% efficient) compared to 0.5% of many modern speakers and thier space heater modern amps- go figure........................
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Amplification (Pre/Power) / Re: How to Build a killer Amp
« Last post by vitavoxdude on January 03, 2018, 12:19:40 PM »
ooops, just looked at the earlier post of the CD and I can see the B+ switch off to the LHS...my bad.
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Amplification (Pre/Power) / Re: How to Build a killer Amp
« Last post by vitavoxdude on January 03, 2018, 12:12:24 PM »
Hi Steve.  Will the Dueland be happy at that voltage? those stacked copper foils do not have the greatest of reliability at anything over 100 or so volts.  I see the VSF DC copper caps have a 400v rating so maybe at UKP-165 each they should hold up.  Do you employ a delayed switch on for the B+ in your circuit?

The PC networking cable wiring you are using, what brand is it?  I bought 500m of the stuff, but it turns out what I thought was CAT6 cable was from china and recycled WW11 aircraft body parts coated in what appears to be darkly tarnished oxidized recycled copper...................bloody awful stuff, you can tell by just holding the stuff, proper copper has around 3 times the weight and is no where near as flexible.  Others be warned, go to the likes of Belden cables and avoid this SHeeeeeeeT.  Ozzy re sellers must make a packet on re selling it into our market.
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Amplification (Pre/Power) / Re: How to Build a killer Amp
« Last post by stevenvalve on January 03, 2018, 01:18:43 AM »
I needed less voltage to run the RCA 45 tubes max 250v, instead of 50s max 450v, so i used a .47uf Duelund capacitor instead of a 45uf solen on the output of the rectifier, the voltage went down from 280v to 218v prefect for the 45 valves. The .47 has little affect on increasing the voltage unlike the a 15uf, but still seems to lower the noise floor.
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Amplification (Pre/Power) / Re: How to Build a killer Amp
« Last post by stevenvalve on January 03, 2018, 01:01:10 AM »
Best to run around 300v/0/300v to the rectifier. 400V/0/400v will probably have to much voltage, especially if you run the 15uf cap on the voltage out of the rectifier. The 15 uf cap is needed to lower the noise floor but it is a case of diminishing returns, a bigger cap will probably not lower it much more anyway, but it will not hurt. The other advantage of the 15uf cap is you get a voltage increase and that will allow you to run a lower voltage mains transformer. The UX250 or type 50 is good for 450 volts, but dont run that because that will shorten the life of your hard to find UX250 globes and could make them sound stressed. I run 250v/0/250v and that gives me around 280v-300v at the valve. the B+ switch is used to let the valves warm up before adding the currant, helps the valves last a lot longer. I must say my UX250 globe amplifier running this circuit is so good it is the end game for me, it really does sound real, but to get it there you must use the right bits and tune it correctly. My PX/4 amplifier is running the same circuit and same parts combination.
To help lower the AC filament noise run a 100R resistor from one 6.3v filament wire to ground as seen in the picture
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Announcements / Re: Seasons greetings to all our contributors
« Last post by kajak12 on January 02, 2018, 11:50:36 PM »
merry christmas all from lovely perth
oh and a happy new year
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Other DACs / Re: Marantz cd99 se limited .
« Last post by brenden on January 01, 2018, 01:43:24 PM »
Yep . Same chassis.
   The cd99 se limited  recieved lots of nice refinements trickled down from the cd12  but with the dual differential circuit of  the CD 94 mk2 . The cd99 and the later cd7 were the only machines to recieve the double crowns .
  Some refinements are apparent ,  some are not so apparent .eg a look at the main elna caps  you will notice the thick rubber  vibration /resonance control  on the  top. This was obviously a custom elna cap made  for Marantz . 
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Announcements / Re: Seasons greetings to all our contributors
« Last post by gamve on January 01, 2018, 07:51:38 AM »
Yep. Merry Christmas from sunny Queensland
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