All resistor produce noise when a current passes.
Some resistors produce a bit of extra noise.
Metal Oxide resistor do produce a bit of that extra noise compared to metal resistors.
The added effect is marginal in most of audio.
Carbon is a very noisy animal !
Metal Oxide is recognised as a good resistor material for most uses. Just not quite as good as metal. But it does have slightly better transient handling capability.
Some resistors produce a bit of extra noise.
Metal Oxide resistor do produce a bit of that extra noise compared to metal resistors.
The added effect is marginal in most of audio.
Carbon is a very noisy animal !
Metal Oxide is recognised as a good resistor material for most uses. Just not quite as good as metal. But it does have slightly better transient handling capability.
Hello,
Why not use mills 0.33 ohm 5 watt wire wound?
I remember well changing the original 1K8 ohm Shinkoh tantal resistor into a 2Kohm 2 watt Allen Bradley was a nice improvement. The maximal value was 2K4 for a power supply of 24 volts.
Of course you could also use Lundahl LL1694 or ll2733 instead of the wirewound resistor between the power supply caps.
greetings, Eduard
Why not use mills 0.33 ohm 5 watt wire wound?
I remember well changing the original 1K8 ohm Shinkoh tantal resistor into a 2Kohm 2 watt Allen Bradley was a nice improvement. The maximal value was 2K4 for a power supply of 24 volts.
Of course you could also use Lundahl LL1694 or ll2733 instead of the wirewound resistor between the power supply caps.
greetings, Eduard
I have a mills in there now. But someone said that changing the .33 wirewound to 3x 1R MOX makes a BIG difference!
Now I will just try the MOX ones and some metal ones to see what sounds better.
And yes, I am taking the Hiraga apart to fit the Lundahl LL2733 chokes. Need a different PSU because they just don't fit right now.
Any other thoughts on resistor changes that improve this amp?
Verzonden vanaf mijn iPhone met Tapatalk
Now I will just try the MOX ones and some metal ones to see what sounds better.
And yes, I am taking the Hiraga apart to fit the Lundahl LL2733 chokes. Need a different PSU because they just don't fit right now.
Any other thoughts on resistor changes that improve this amp?
Verzonden vanaf mijn iPhone met Tapatalk
Hello Sjoerd,
The best resistors used in the hiraga amp were the the original shinkos sold in Paris. But the 1k8 was not as good as a 2 watt Alan Bradley. If i remember well i did use another value i think 2K or 2k2 . Maximum is 2K4 with a 24 volt power supply. They were 2K just found them but only 2 and you will need 4. Maybe i have more but where?
Probably the better sound could be explained by the 0,5 watt being to low. Still can get 2 watt AB in the UK or even Shinko 2 watt. I do remember it was a nice improvement thast i made about 30 years ago. Can also mount the drivers on the same heatsink with ISOLATION so they work on the same te,mpertature.
Greetings, Eduard
The best resistors used in the hiraga amp were the the original shinkos sold in Paris. But the 1k8 was not as good as a 2 watt Alan Bradley. If i remember well i did use another value i think 2K or 2k2 . Maximum is 2K4 with a 24 volt power supply. They were 2K just found them but only 2 and you will need 4. Maybe i have more but where?
Probably the better sound could be explained by the 0,5 watt being to low. Still can get 2 watt AB in the UK or even Shinko 2 watt. I do remember it was a nice improvement thast i made about 30 years ago. Can also mount the drivers on the same heatsink with ISOLATION so they work on the same te,mpertature.
Greetings, Eduard
Hi Eduard,
I do have the Shinkoh's for two amps over here. They are on two old boards that never worked [emoji6] AB's drift don't they? I have 32VDC rail voltage so I will stay with 1.8k. If anyone has any ideas for that value with my rail voltage, I am glad to hear them.
Your comment on the drivers is something I have been thinking about a lot! But how? Long leads is not good.... Or is there a rule of thumb on how long leads can be. And do you use solid or stranded wire for that? I do think it's a really good idea to mount them on the same heatsink as the output devices...
Kind regards,
Sjoerd
I do have the Shinkoh's for two amps over here. They are on two old boards that never worked [emoji6] AB's drift don't they? I have 32VDC rail voltage so I will stay with 1.8k. If anyone has any ideas for that value with my rail voltage, I am glad to hear them.
Your comment on the drivers is something I have been thinking about a lot! But how? Long leads is not good.... Or is there a rule of thumb on how long leads can be. And do you use solid or stranded wire for that? I do think it's a really good idea to mount them on the same heatsink as the output devices...
Kind regards,
Sjoerd
Hello Sjoerd Not mount them on the same heatsink as the power transistors because they will not survive. Because i work in a metal company i just made a piece of 3 mm aluminium with some clearance in the middle because there was the original cosmos pot to adjust dc at output.. Before having this aluminium attached i remember when you did touch one of the drivers and therefore heating it up a little more dc at output would change. If you touch the other driver DC would go the other side. SO good to have them at similar temperature. If i remember well the transistors were facing in opposite directions so it is hard to get them on the same line... Better desolder the drivers mount them on the aluminium well isolated, maybe give the alu a little bend in between the drivers and solder them again. If you mount them while they are still attached to the board you might put to much stress on the soldering joints.
Because the AB i used were 2 watt they did not drift that much.lol Never did have any problem with that.
I use LL2733 in my DDDAC and i did suggest soime people to use the Lundahl chokes in Hiraga or Pass design. My friend Vietnam will use them but only after i did bring them on my next holiday lol
Greetings, Eduard
p.s with higher power supply you can use higher value than 1K8 . Like i said the AB were a big improvement.
Because the AB i used were 2 watt they did not drift that much.lol Never did have any problem with that.
I use LL2733 in my DDDAC and i did suggest soime people to use the Lundahl chokes in Hiraga or Pass design. My friend Vietnam will use them but only after i did bring them on my next holiday lol
Greetings, Eduard
p.s with higher power supply you can use higher value than 1K8 . Like i said the AB were a big improvement.
Thanks! I could try the 2K AB's and see how I like it 
I have the drivers on separate Fischer heatsinks. That does work well so I'll take your word for it
I will try to connect the sinks of both drivers so they will have the same temp. That should do some good. I allways insulate drivers / power transistors with keratherm.
Thanks!
I have the drivers on separate Fischer heatsinks. That does work well so I'll take your word for it
I will try to connect the sinks of both drivers so they will have the same temp. That should do some good. I allways insulate drivers / power transistors with keratherm.
Thanks!
Hello,
In the past one of the Holco sellers in the UK did warn about the holcos being very fragile when bending the leads. I did look for more AB but 2K 2 watt only have 2
Hifi collective has them and they have a tip about heating them up in an oven and then seal them to make them less sensitive to drifting and water absorption. They also have 2 watt audio note tantal. But they are expensive. But even at that price i consider them cheap after all i still remember the improvement the cheap 2 watt AB gave to me in the eighties.
greetings, eduard
In the past one of the Holco sellers in the UK did warn about the holcos being very fragile when bending the leads. I did look for more AB but 2K 2 watt only have 2
Hifi collective has them and they have a tip about heating them up in an oven and then seal them to make them less sensitive to drifting and water absorption. They also have 2 watt audio note tantal. But they are expensive. But even at that price i consider them cheap after all i still remember the improvement the cheap 2 watt AB gave to me in the eighties.
greetings, eduard
Hello Sjoerd,
Sure put them in. Which 1K8 are there in use now?
I hope the improvement i did get was not coming from changing tantale into carbon composition but just the higher wattage. I know Hirga did like both AB and Shinkoh at that time.
Changing 1k8 into 2K could be part of the improvement too.
We will soon know.
Greetings, eduard
Sure put them in. Which 1K8 are there in use now?
I hope the improvement i did get was not coming from changing tantale into carbon composition but just the higher wattage. I know Hirga did like both AB and Shinkoh at that time.
Changing 1k8 into 2K could be part of the improvement too.
We will soon know.
Greetings, eduard
Right now it's kiwame 5 watt carbon film. The whole amp is done with Kiwame 2 watt carbon film resistors. Nice and sweet sounding resistors. On the power trannies I now have 5 watt Mills 0.33ohm resistors.
My plan is to:
Change the 0.33 Mills into Mundorf M-resist supreme 20watt 0.33ohm
Change the 5 Watt Kiwames for 2 watt Shinkoh 1.8k
Change the kiwames that are in the offset path for metal film ones... Don't know what brand yet, thinking about the PRP ones hifi collective has. I'll go for the 0.5 watt ones.
Changing the 68pf caps on the drivers to Silver Mica(now polystyrene)
Changing the whole PSU so the Lundahl's will fit [emoji106] and also changing some values on the caps in the PSU as suggested to me by Eldam.
So, no quicky [emoji6]
Kind regards,
Sjoerd
My plan is to:
Change the 0.33 Mills into Mundorf M-resist supreme 20watt 0.33ohm
Change the 5 Watt Kiwames for 2 watt Shinkoh 1.8k
Change the kiwames that are in the offset path for metal film ones... Don't know what brand yet, thinking about the PRP ones hifi collective has. I'll go for the 0.5 watt ones.
Changing the 68pf caps on the drivers to Silver Mica(now polystyrene)
Changing the whole PSU so the Lundahl's will fit [emoji106] and also changing some values on the caps in the PSU as suggested to me by Eldam.
So, no quicky [emoji6]
Kind regards,
Sjoerd
Good one AndrewT. Whoever gives the right answer gets the cake! [emoji6]
I know Pink Faun uses AB's all around and they know business. But everywhere I read those things seem to lose because of the high(ish) abillity to absorb moisture thus drifting. Never tried them because of this.
I read too much [emoji6][emoji23]
Hi Andrew,
Thanks for the input. I have readed for quite a will about these noises. In the thread "the best dac is no dac" our colleagues from there did measured the noise differences with a scope if i remember well, and the conclusion was that in the RN series from Visay, the 2w resistors had -6dB lower noise than an ordinary 0.125 or 0.25w resistors and the 2watters gave a more cleaner sound. Interesting...
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.