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Resistor question

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#81
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#83
I must admit,

Subjectively I think I hear a difference with different resistors, however this has been the case since the early 70's. If I try to put it in words what I think I hear its this..

Lets say I try resistor 1..
it sounds OK no problem.
Resistor 2 seems to have a bright edge to the treble.
Resistor 3 has a bloated bass but it seems to be deeper.
Resistor 4 is just unlistenable compared to the others.
Resistor 5 sounds smoother but the highs seem rolled off.

I could give a subjective thought about comparison of the so called audio resistors but I don't think it would help.
A mix of Kiwame in the anode and Takman MF in the grid etc it sounds a bit like Tantalum but the highs are slightly rolled off.
If I compare mills to a standard cement resistor the mills sound (its hard to put in words) darker with what appears to be more bass but that's not quite right..its like the bass is more pronounced and highs seem smoother. Its a bit like moolys op amp test..same kind of sound change.
Warmer or harder more pronounced bass hash on the highs is less or more..

BUT..and here is the problem if you put in resistors that seem to give a warmer sound it can become like the highs have gone and bass impact is reduced.
Its very strange..OK its non existant..but its still strange. The old RS carbon film seem to give an even balance..if you compare to MF you seem to be able to hear a glare that is not there with the CF.

I think this is the problem..when you think you have heard this difference you can't go back to thinking its all self induced..and you can't just put in any cheap MF..OK cost is not the issue but I have noticed this with even cheap components. This could be imagination but put Tantalum in the wrong place and it sounds awful..but its just a standard resistor so there should be no difference. OK so is it the conductive resistor element (what its made of) its very strange...way back in the past I even took RS carbon film resistor and cut the leads off then ground away as much of the end cap as I could and soldered silver wire in place of it, because I thought I heard a difference..Yes its sounds mad but that is what can happen..This "Mod" is still in a couple of amps I have today. You can become obsessed with it. And what makes it even worse is when you think its all make believe change a component and you still think you can hear a difference! So where do you go from here ..all you can do is put in what you think is the best sound (because all resistors sound the same)..so it doesn't matter what you fit. Because I have tried removing all resistor from an amp and changing the whole lot to a different type..then took them all out again because I missed the old sound. The problem is sometimes you do something like this and (Yes I know its all rubbish) the family say what have you done to that it sounds rubbish. and wont use it!

Regards
M. Gregg
 
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#85
I even tried replacing a copper wire with silver on the aerial of an old valve radio and could measure an increase in signal, the radio became more sensitive to stations but was it the silver wire or the silver solder..

In the end you have to take a back seat and watch everyone else argue over it..😀
You try to measure it but to no avail and try to convince yourself its all make believe..but it doesn't work your hooked..
If you put FB on the circuit you can reduce the effect..but its still got you!

Regards
M. Gregg
 
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#86
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#87
Well, I for argue sake i put the original resistors back in and for sure the amp sounded muffled lacking high end detail and bass respons went down. Took them out again and put the Allen Bradleys back in and the amp sounds great, with great high end detail and beautiful deep bass response.

I think its a sum of the parts. Its a noticeable improvement.
 
#88
Dephazer said:
I think its a sum of the parts. Its a noticeable improvement.
Click to expand...

Signature of carbon is open sound with smooth highs and what can be a bit warm in the bass..but that's what I think I hear..however try and measure it..there is no change..

NB I'm not saying there is no change just that this has been a bone of contention since HIFI began..its refered to as snake oil..its why many years ago I threw all my HIFI in the bin and bought a MIDFI..But it wasn't long before there was a valve preamp on the front end..and so it goes on.

The sum of parts is referred to as synergy in the Audiophile camp..😀
ie the interaction of the parts creating a bigger improvement than a single part..ie its the reaction of the circuit to the different components..but as many will tell you there are no different components..or should I say a resistor is a resistor..you can hear a similar change with solder types but that is another imagined effect...well so they say..
What I would add is not everything is as said in the audiophile camp some of it is complete C..p.. so its a hard line to walk..😀

Regards
M. Gregg
 
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#89
M Gregg said:
The link doesn't work I can't open it..🙂

NB its would seem like audio note are also hooked on it..even to the extent of wooden PCB's..so at least its a consolation that others are just as mad.😀

Regards
M. Gregg
Click to expand...
Maybe 😀 I tought it before i tried ... 😉
For the Seifert paper : gogol for "Seifert resistors 2009" , you'll get it 🙂
And don't forget : "more is less" (components) but "more is more" (material)
 
#91
M Gregg said:
I even tried replacing a copper wire with silver on the aerial of an old valve radio and could measure an increase in signal, the radio became more sensitive to stations but was it the silver wire or the silver solder..
Click to expand...
"Measure"? Please share your measurements with us. Microvolts or dBm are equally acceptable.

Dephazer said:
Well, I for argue sake i put the original resistors back in and for sure the amp sounded muffled lacking high end detail and bass respons went down.
Click to expand...
"Bass respons went down" is an objective statement of LF reduction. "Muffled" is of course subjective, but implies HF reduction. So a change of resistor reduced bandwidth at both ends of the audio spectrum? If so, why do people bother with bandpass filters when all they need to do is use the appropriate resistors?
 
#93
Dephazer said:
Well, I for argue sake i put the original resistors back in and for sure the amp sounded muffled lacking high end detail and bass respons went down. Took them out again and put the Allen Bradleys back in and the amp sounds great, with great high end detail and beautiful deep bass response.

I think its a sum of the parts. Its a noticeable improvement.
Click to expand...

If you have the test equipment I think you will find higher IM distortion with the old resistors. If you just have any way to create two tones (Say from a computer sound card) then you can just introduce 19,000 and 20,000 hertz at a moderate level (well below amplifier clipping) and observe how much 1,000 hertz comes out with each set of resistors. Even listening to the difference on a small loudspeaker should show a difference. (But you might want to disconnect the tweeter to prevent it getting damaged.
 
#94
Picked up a new in box Palcom TA-70 today for 200 euro. In essense its the same as a Dynavox VR-70.
Sounded allright out of the box. Nothing special so I opened her up and took out all the cheap junk caps and put in TJ Jensen Foil caps. Then put in NOS RCA 6U8A blackplates.
Wow!! This amp just woke up 🙂
 
#97
I first swapped the tubes. Nice improvement, but still a bit lacking in high end detail and pressence. So i took out all the brown turd Chinese ceramic caps and replaced them with high quality Jensen Foils. That made a big improvement in the overal soundstage.
Next is taking the stock wiring out and replace that, aswell as the crappy volume pot.

Now...should i get rid of the metal film resistors? Hehe
 
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#98
I know... I said they would stay in a while...
Well, threw out the Chinese EL-34's and in went NOS Tung Sol 5881's. Rebiased the amp and that made the biggest change. Lush beautiful tube sound just pooring into the room.
So much definition, cristal clear highs, deep firm lows. Vocals are amazing.
 
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#99
There are two main issues with capacitors. One is dissipation factor or a loss that increases with frequency. It gets worse the higher the voltage rating for any given film type. The second is distortion it gets better with higher voltage ratings. Now foil capacitors have a bit lower internal resistance and can handle higher currents, usually not as big a deal in tube circuitry. Before you try silver wire you might just want to resolder all the joints with any good eutetic solder.
 
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