Hi Ryanj,
Blatant newbie question coming up!!
Sorry to bother yet again, i would like a passive I to V converter with Rhopoint resistor, however there seem different opinions about the value of such an item, as there quite expensive, can you give me a definitive (or best ball park) resistance value i should order for best results (min distortion/best gain?)- and.........
I also have a Lampizator SRPP PCB and assume that the same value resistor would be OK to feed that (if you are familiar with the Lampa SRPP PCB?)
Thank you for your patience here, i do appreciate it.
Best regards
Johnny
Blatant newbie question coming up!!
Sorry to bother yet again, i would like a passive I to V converter with Rhopoint resistor, however there seem different opinions about the value of such an item, as there quite expensive, can you give me a definitive (or best ball park) resistance value i should order for best results (min distortion/best gain?)- and.........
I also have a Lampizator SRPP PCB and assume that the same value resistor would be OK to feed that (if you are familiar with the Lampa SRPP PCB?)
Thank you for your patience here, i do appreciate it.
Best regards
Johnny
I will defer to Ryan as the expert, but offer my experience for consideration. I have run several Lampizator/1541a rigs. As you know he advocates 100r as the optimum value for the I/V resistor. I used 100r for some time and it is fine. As he says, it produces a sharper edgier sound vs lower values. I saw arguments for something more like 60r as a lower distortion 'optimum' value. I now use a DIY manganan IV resistor at 60r feeding a point to point wired Lampizator circuit. I think the sound is excellent feeding my objective of relaxed clean 'in the room' sound. I believe a hand wound manganin resistor is functionally equivalent to the Rhopoint. It certainly mopped the floor with every other resistor I tried including vintage AudioNote and Caddock TF - UFS series. I think the solution to your decision could be to use less expensive IV resistors at values between 50r and 100r. When you decide what value suites your objectives best, swap in that value of the Rhopoint. It will let your preferred sound shine through without the distortion of lessor resistors.
I know they are expensive but consider using the Rhopoint for the other resistors in the Lampizator circuit. I believe they are 200r in my circuit. The manganins made an equal jump in sound quality improvement there as they did with the I/V.
I know they are expensive but consider using the Rhopoint for the other resistors in the Lampizator circuit. I believe they are 200r in my circuit. The manganins made an equal jump in sound quality improvement there as they did with the I/V.
Hi Johnny,
The Rhopoints are well worth the money, to me they sounded better than those naked vishay resistors, and were a bit better than some CuNi44 wire that I used to make up some honeycombe wire wound resistors. If your using the SRPP I think I used 100R, and it sounded good at this value, as Walter said, you will achieve lower distortion the lower in value you go. At the moment for my output stage (CEN/current conveyor) im using 1k5 Rhopoints and am very satisfied with them. You might want to go the option of what sumotan suggests first to get a feel for the sound difference in using different IV resistors, they all sound different.
Have fun with it.
Ryan
The Rhopoints are well worth the money, to me they sounded better than those naked vishay resistors, and were a bit better than some CuNi44 wire that I used to make up some honeycombe wire wound resistors. If your using the SRPP I think I used 100R, and it sounded good at this value, as Walter said, you will achieve lower distortion the lower in value you go. At the moment for my output stage (CEN/current conveyor) im using 1k5 Rhopoints and am very satisfied with them. You might want to go the option of what sumotan suggests first to get a feel for the sound difference in using different IV resistors, they all sound different.
Have fun with it.
Ryan
You will enjoy these resistor experiments. FYI, I wrote a short blog concerning my fun in this regard.
2013 Holiday Projects - Ridding the system of resistor problems - diyAudio
Later I also changed the cathode resistors to Manganin and realized equal benefits. Values of all are in the attached schematic.
For fun I attach a pic of the circuit wired pt to pt. The white blobs are the hand made resistors. Not pretty, but sound is sublime.
I came to the conclusion that all resistors near the signal path are evil and should be eliminated where possible and replaced with least damaging element which to my experience is manganin. I believe this is what Rhopoint uses as their resistive element.
2013 Holiday Projects - Ridding the system of resistor problems - diyAudio
Later I also changed the cathode resistors to Manganin and realized equal benefits. Values of all are in the attached schematic.
For fun I attach a pic of the circuit wired pt to pt. The white blobs are the hand made resistors. Not pretty, but sound is sublime.
I came to the conclusion that all resistors near the signal path are evil and should be eliminated where possible and replaced with least damaging element which to my experience is manganin. I believe this is what Rhopoint uses as their resistive element.
Attachments
There's some values at Farnell's (Element 14, out here) either in the 8G16 or smaller ones - quite expensive for single units - you have to pay a surcharge at Rhopoint for small quantities that pushes the cost up a lot.
You can still get some enameled Manganin wire on eBay - simple search shows "prommark" as a stockist -
I've mainly used the wire from Isabellenhutte or their power resistors - there's plenty of the Mn wire still made in different countries but expensive in small quantities (ie Lake Shore in the US) - maybe it's available cheaper from China if you can get just a couple of reels but, and there is one unfortunately.
One of the guys here bought some China Isotan wire but it didn't have the same sound as the older European Isotan/Constantan wire even tho it had identical specs - this could be the same with their Manganin wire - just saying, mind you ...
You can still get some enameled Manganin wire on eBay - simple search shows "prommark" as a stockist -
I've mainly used the wire from Isabellenhutte or their power resistors - there's plenty of the Mn wire still made in different countries but expensive in small quantities (ie Lake Shore in the US) - maybe it's available cheaper from China if you can get just a couple of reels but, and there is one unfortunately.
One of the guys here bought some China Isotan wire but it didn't have the same sound as the older European Isotan/Constantan wire even tho it had identical specs - this could be the same with their Manganin wire - just saying, mind you ...
If one were to spend the money on Rhopoint,
guess it’s only logical for purchase the squaristor
series . Aside from Rhopoints, I’ve tried quite a variety
of resistors from carbon, tantulum to metal film of different
brands. Last on trial were the Mills Mra 5w & it’s been permanent.
Really good sound, perhaps will try Rhopoint sometime.
guess it’s only logical for purchase the squaristor
series . Aside from Rhopoints, I’ve tried quite a variety
of resistors from carbon, tantulum to metal film of different
brands. Last on trial were the Mills Mra 5w & it’s been permanent.
Really good sound, perhaps will try Rhopoint sometime.
Not much difference between the 2 forms, except prices - the 8G16s are called 'Econistor" for a reason - the Squaristors (GG102s) are smaller for higher build density
I'm not sure of this but I think the Mills power resistors are built with either an Isotan or a Nichrome wire - they have a quite different sound to the Manganin - they might indeed, suit your system perfectly.
I'm not sure of this but I think the Mills power resistors are built with either an Isotan or a Nichrome wire - they have a quite different sound to the Manganin - they might indeed, suit your system perfectly.
Like what you say James, Im sure they will sound different.
But is it going to be better really don’t know. My take is, this
I/V resistor is not the be it or be all that dictates the overall
quality of the sound, what’s around it plays a major roll as
well. I myself have discover that using super good stuff does
not necessarily equals good sound. It’s really a synergy of
parts & circuit design. Having said that Im always curious so
will try out the Rhopoints when I get the itch. lol
Cheers
But is it going to be better really don’t know. My take is, this
I/V resistor is not the be it or be all that dictates the overall
quality of the sound, what’s around it plays a major roll as
well. I myself have discover that using super good stuff does
not necessarily equals good sound. It’s really a synergy of
parts & circuit design. Having said that Im always curious so
will try out the Rhopoints when I get the itch. lol
Cheers
attenuator board
Hi Ryan, I am building my distinction V1 at the moment, I would like to use the attenuators from your V2 board. Is the board from your first post available? I would like to add it to my build. I would happily get some made if you provide the gerbers.
Thanks in advance.
Hi Ryan, I am building my distinction V1 at the moment, I would like to use the attenuators from your V2 board. Is the board from your first post available? I would like to add it to my build. I would happily get some made if you provide the gerbers.
Thanks in advance.
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