Non-NOS component choices

[rootz]

The topic of which component to choose and for which spot is old, very old. Lots of info about this can already be found on Ampgarage and it is pretty easy to find all about NOS parts and build an amp based on that. IF you can find the NOS parts!

Info about new components is much scarcer, at least meaningful info to me. I can't find much, although I extensively use the search function.

In this thread I want to ask you about experiences concerning modern day resistors. What comes close to the NOS counterparts, or what differences do you hear between vintage and new parts compared, or new nd new parts compared. You're more than welcome to say that you don't hear a difference, but I'd like to hear more observations along the lines of NOS vs new RN65D resistors. So for example what difference do you hear between NOS RN65D's, new ones and Holco's? The latter are readily available, unlike 100k NOS RN65D's. I, for one, hear a distinct difference between NOS and new RN65D's, preferring the NOS parts.

For the record: I, and we all, know not 1 resistor is going to make all the difference. We also know ordinary parts can make a perfectly fine amp. We also know hearing and interpretation is highly subjective, which can lead to contradictory views.

I'll give an example. I made a Marshall JTM50 with Takman REX (carbon film resistors. I thought that compared to the Xicons that were in my amp before the makeover the Takmans were more detailed but also lacked character in that amp. Which by the way might to might not say much about them in a Dumble clone.

Note, I'm looking to improve my amps without braking the bank or using much of my scarce time to search for the NOS needle in the haystack.

[10thTx]

This is all from a previous post of mine trying Kiwame carbon film out in a D-inspired amp, my Carolina Overdrive Special with 5879 OD

I'll throw this in the mix for anyone wanting to consider trying out other resistors. One of my D-inspired amps (but not a clone) had the Vishay Dale RN65 resistors. I tried some of these
2w carbon film Kiwame resistors on the plates of the clean stage, OD stage, FX loop and LTPI. I was hoping that given they were 2 watt resistors that they would lower floor noise some which I don't think they did. My understanding is they may be the same as the KOA Speer resistors?

https://www.partsconnexion.com/kiwame-2 ... stors.html

I do think the amp is a little sweeter musically after installing them and perhaps sustained a tad more? I personally don't hear the RN65's as harsh but I do think they are somewhat brighter then the kiwames. Since it's not a D clone, I acknowledge this more of an apples to oranges comparison.

With respect, 10thtx

[10thTx]

And this is from a PM that I sent another TAG member regarding TKD 2 watt metal film resistors (which have become my favorite plate resistors):

OK, I put the TKD 2w metal film resistors in. Pretty dramatic difference in tone, IMO. This is going to be sort of hard to explain, so cut me some slack in the description please.

Same amp. I first had RN65 Dales (the Mouser ones). I then tried the Kiwame 2w carbon film which I liked better and thought they sounded more musical and sweet especially on the OD channel. However, they did nothing to lower floor noise so I wanted to try 2w metal film & that led me to the TKD resistors.

In my thinking, I hear a difference between clear and clean. I think one can have a clear overdrive that is not distorted but does sound pushed or overdriven but is very musical sweet and has nice harmonics. I think of clear where when chording, you still can easily pick out every note. [ And I think there is a distinction between clean tone (Fender Twin) and a distorted tone like a cranked Marshall.]

I hear clear to distorted as one spectrum. I hear clean to Overdriven as another spectrum.

I like these TKD resistors. I replaced them on 6 plates. I have 3 gain stages on clean. And two gain stages on OD (latter one being a 5879 pentode) going into an active FX. That's what got replaced. The amp did have some hiss/white noise but had a small amount of "buzz" also (almost single coil-ish type noise without using single coils). The TKD resistors totally lowered the floor noise. On the clean channel only white noise/slight hiss.
The OD channel has 70% hiss/30% some slight buzz still.

This is the clearest most musical harmonically rich (sort of 3D-ish) clean tone I've ever gotten on any amp I've owned or played. This is sort of that Larry Carlton playing with Fourplay clean tone. Amazing! I have a friend who had an tweed Super. First time I heard it, I thought it had reverb but it didn't. It was that full/dimensional sounding without reverb. These resistors sort of did that dimensional musical harmonically swirly thing but with a VERY clear (in contrast to clean) tone.

On the OD, it sounds so clear and transparent that I initially couldn't tell whether I was on the clean channel or OD channel until I looked at the footswitch light? In other words, the amp had the OD on when I first started listening to the resistor change but I had to look at the footswitch to see that. Yes, the overdrive tone is still there but with less distortion. Prior to the resistor change, I think I could probably get any distortion tone I needed thru the amp without a pedal. Not so sure now? I'm thinking if I were playing slide, I'd want one of my OD pedals involved?

Verdict, great improvement on clean tone. OD tone is just different not necessarily better. I don't like the OD any more or any less then with the Kiwames. Just a different tone, IMO. I think the Kiwame's and the TKDs sound better used on the plates then the modern RN65's.

Downside of the TKD's. They are the same size as the OD PS .0047 caps! This is a big resistor! I use paralleled turret boards similar to Hiwatt in my amps, so they work Ok for that. The TKD's might not be useable on a small tight board? And the wire leads are fairly thick wire. You have to take extra care wrapping them around a turret and squeezing them tight.

I think these TKD resistors would be fantastic for any jazz tube amp, Small Special with only clean channel, maybe a AB763 and maybe a SSS Dumble? Don't know if they'd be the best choice for a Dumble used primarily for a rock tone? I think the TKD's are sort of hi-fi-ish in their musical clarity without sounding hi-fi-ish sterile and lifeless.

I have a small jazz practice amp (HoSo56 Minimalist) that I like and play thru a lot at home. I plan to put the TKD's in it also. My other amp, the Tweed BluezMeister …………. I wouldn't consider the TKD's for it at all. It has it's own tone and I like the distortion with the OD on the TBM amp.

Just my thoughts and observations ……………… Best regards and respect, Jeff aka 10thtx

Just an update ……….. I've gotten some hours in on the TKD 2w metal film resistors in my Carolina Overdrive Special amp. These definitely are my favorites of all I've tried.

I really like these resistors ALOT. Very smooth, very clear/articulate, and they lower the floor noise. Very happy with them!

Only downside that I have found is because of size and thickness of lead wires, they are clumsy to solder.

[Colossal]

I can concur that my experience with the new issue RN65s (and not in a D style amp) was that they were indeed brighter. Obviously so; quite interesting. They are not my preference, however, and I don't use them. In the past, I've used Kiwame/KOA Speer 2W CFs with good results in various amps. Recently, I have moved away from Sozo caps, but I am also not really building the usual fare that calls for them. I find I prefer SBE 6PS polyester film foils. Takmans have good clarity but might be interpreted as kind of plain, but not bad sounding per se. I used to use 3W IRC metal films, but they were discontinued. They were quite warm sounding and very quiet. Hmm, what else....

[rootz]

Thanks Jeff and Colossal. Odd, I interpreted the sound samples of the RN65D comparison as the NOS ones as being a bit brighter and detailed in OD, but also less harsh at the same time. Need to listen to those again.

Good points on the Kiwame 2 Watters Jeff. Those are reasonably small too. Those TKD's on the other hand! 18mm long . TKD is the Correctohm CM Series, right? I can only find them at hificollective in the UK. More sources?

Keep 'm coming guys, I think this is very interesting (might interest others too, at least I hope so).

Would love to see how those TKD's compare to NOS RN65D. It's a pity NOS is so damn hard to find these days. I would opt for 105k or 97k5 too, close enough.

[10thTx]

I got the TKD 2 watt metal film resistors at PartsConnexion. I don't mind sharing that now, since I've got a small stash of them saved up.

With respect, 10thtx

[Bombacaototal]

Very interesting thread! Very nice to learn from all here. I am a NOS fanatic but have done some experiments comparing with current parts and happy to share some of my perceptions/findings. I would love to transition to all current and “subscribed” to this thread

For resistors I only use NOS beyschlag/piher or draloric and therefore cannot contribute much, expect on plates when I use the new production RN65D. I have tried MF 1W KOA on plates but found it horrible, extremely brittle and uninteresting.

https://www.mouser.co.uk/ProductDetail/ ... cycode=GBP

On the capacitor side I managed to experiment a bit more. As far as decoupling caps for tonestack and dry/wet mix (amps with reverb) I found that new production .02uF, .01uF the 6PS (1600V) almost always sounds better than the NOS 6PS (600V) but they are huge, and therefore not practical for higher values. They have a nice controlled presence which I like. On the tonestack the NOS are almost always better to my ears.
For bypass capacitors I like the Sprague High Temp (silver) in strategic positions if the amp is lacking life and top. The 63V blue Phillips are fairly warm for new production and were used by Two Rock (although not sure they have been discontinued). I found they are usable too strategically but to my ears they lack that fatness of the yellow NOS sprague. I unfortunately still haven’t found a bypass cap that sounds better than the yellow, but would love to hear what you guys are using.

[10thTx]

The only thing I have to add about caps is that with an on board FX loop, I like using MusiCaps in the FX loop. They're super transparent and close to a "hi-fi" tone. My impression is that the FX loop with MusiCaps doesn't alter the tone or the amp the way the OD 6PS caps do. I did A/B them in the loop.

They're also expensive and pretty hard to find. I built one amp with MusiCaps in numerous places and it was way super transparent and lacked warmth and I went and removed them & put the OD 6PS in. So, for me …… almost exclusively in the FX loop.

There was a thread some months ago about silver mica caps vs. different types of ceramic caps. I'm not using the silver mica caps anymore and have switched over to the ceramic ones.

With respect, 10thtx

[Colossal]

As far as decoupling caps for tonestack and dry/wet mix (amps with reverb) I found that new production .02uF, .01uF the 6PS (1600V) almost always sounds better than the NOS 6PS (600V) but they are huge, and therefore not practical for higher values. They have a nice controlled presence which I like. On the tonestack the NOS are almost always better to my ears.

Raphael,

The 1600V 6PS, are they polyester or polypropylene? I thought the 600V 6PS were polyester film foil and the 1600V, polypropylene. Please see the attached datasheet.

Dave

SBE 6PS Datasheet.pdf

[Bombacaototal]

As far as decoupling caps for tonestack and dry/wet mix (amps with reverb) I found that new production .02uF, .01uF the 6PS (1600V) almost always sounds better than the NOS 6PS (600V) but they are huge, and therefore not practical for higher values. They have a nice controlled presence which I like. On the tonestack the NOS are almost always better to my ears.

Raphael,

The 1600V 6PS, are they polyester or polypropylene? I thought the 600V 6PS were polyester film foil and the 1600V, polypropylene. Please see the attached datasheet.

Dave


SBE 6PS Datasheet.pdf

They are polyester too. Here is the part
https://www.hificollective.co.uk/catalo ... -drop.html

[rootz]

Have a look at that 6ps data sheet again. Especially look for 1600 and 2000 v construction.

[Bombacaototal]

Have a look at that 6ps data sheet again. Especially look for 1600 and 2000 v construction.

Ah, interesting, good to know but to be honest I don’t really mind as I let my ears decide on that one

[rootz]

That’s what counts. HAD sprinkled polypropylene orange drops in some places, so why won’t we or you do that too? Interesting that you use them in the tone stack. 0.01uF, so I guess as a mid cap? I’ve never used polypropylene in the reverb mix, but a 715p would be nice to try!

Another thing that grabbed my attention: at leatst two contributors here on the forum find the Koa Speer MF1 or MF1/2 sub optimal (can’t find a better word). I thought the 2 Watt Koa’s were the same as the Kiwame’s?

[Colossal]

That’s what counts. HAD sprinkled polypropylene orange drops in some places, so why won’t we or you do that too? Interesting that you use them in the tone stack. 0.01uF, so I guess as a mid cap? I’ve never used polypropylene in the reverb mix, but a 715p would be nice to try!

Hi Rootz,

For what it is worth, this is what I do. I know the nature of your question was specifically about non-NOS part choices with respect to building a Dumble style amp, but yes, I use what sounds good for the location. I have been happily surprised by my findings, on occasion, and I do not hold preconceived bias about what part should work where, based on past experiences or expectations for a particular dielectric or resistor type.

Another thing that grabbed my attention: at leatst two contributors here on the forum find the Koa Speer MF1 or MF1/2 sub optimal (can’t find a better word). I thought the 2 Watt Koa’s were the same as the Kiwame’s?

I remember a comment by either Charlie Wilson or Tony Albany that said [paraphrasing] "Kiwames had a thud" . The Kiwames are the 1% tolerance "premium" version of the KOA Speer CF line. Often the KOA Speers test just as precise as the Kiwames, so one may not need to pay the premium. Mouser Electronics here in the US only stocks(ed?) a limited range of them, so I often just got the Kiwames in the specific values I needed from other vendors that stocked the full range. They were not expensive back when I was buying them. They have quite short, thick leads but are very physically robust.

[Bombacaototal]

That’s what counts. HAD sprinkled polypropylene orange drops in some places, so why won’t we or you do that too? Interesting that you use them in the tone stack. 0.01uF, so I guess as a mid cap? I’ve never used polypropylene in the reverb mix, but a 715p would be nice to try!

Another thing that grabbed my attention: at leatst two contributors here on the forum find the Koa Speer MF1 or MF1/2 sub optimal (can’t find a better word). I thought the 2 Watt Koa’s were the same as the Kiwame’s?

True, the final sound is what matters, but good to know HAD made use of polypropylene too.

As far as the tonestack and reverb mix, I use it as a decoupling cap after the recovery stages