Alternate parts for D-style amps?

[Tonegeek]

Dale RN65 resistors seem to be getting scarcer by the minute. Has anyone tried other metal film types as an alternate to the elusive RN65? I would love to also find alternates to the PS series caps. The Vishay MPP caps seem to hold up and sound good, but I have never used them entirely in any amp, only in certain spots.

[dcribbs1412]

Dale RN65 resistors seem to be getting scarcer by the minute. Has anyone tried other metal film types as an alternate to the elusive RN65? I would love to also find alternates to the PS series caps. The Vishay MPP caps seem to hold up and sound good, but I have never used them entirely in any amp, only in certain spots.

Mouser seems to be stocking a few
http://www.mouser.com/Passive-Component ... 65&FS=True
As far as alternates I say experiment, 100k is 100k right
let us know if you can hear a difference(can of worms open...check )
Seriously though, a while back I remember reading Brandon (Blutotone)
stating that any good quality metal/carbon film resistor would be fine.
Just my .02

D

[David Root]

I've used RN65, NOS Electra/MEPCO-Electra MF, PR9372 MF by PRP, Riken CF 1W, NOS Piher CF, NOS Draloric CF, Takman CF and Kiwame 2W CF.

Differences are subtle but if I'm doing a Dumble I'll generally use the same resistors HAD used in that generation circuit. I do have a preference for the Electra/MEPCO-Electra MF vs the RN65 though, and Pihers in the CF, but all the above are good for me.

I recently bought a bunch of current production 2W Stackpole CF for people who don't want to pay for NOS. Only 20 cents each but well reviewed and they actually look like credible 1/2W types ie as big as the old ones, not the size of old 1/4W. Some have steel leads, but then so do Fender blue molded pulls, and they're $20 each now, I stopped worrying about that.

In current production MF look at the PR9372 from PRP. Very good, quiet and smooth; not real expensive either. And the Takman MF should be good too, but I've not tried them.

Haven't looked for 6PS alternatives yet, have some NOS and some current SBE stuff so haven't needed to yet, but it looks like that's coming too.

[Duble]

Why not just use NTE HW metal film resistors, same brand used in all the later dumble amps? The current Dale/Vishay RN65 are much different in composition compared to the Dale resistors seen in Dumble amps anyways.

I've also had great results with Koa Speer 1/2w carbon and metal films.

[Structo]

I believe the NTE components are simply re-labeled brands for distribution.

So when you say, NTE it could be several things.

I have used a lot of the Vishay CCF60 1% metal film resistors from Mouser.

I like them a lot.

They are about the size of a standard 1 watt resistor.

http://www.mouser.com/Search/ProductDet ... CF60-1M-E3

[Mr. dB]

I've seen some photos of de-gooped D. amps that look like they have Roederstein Resista metal films in some positions.

[10thTx]

Regarding using different capacitors other then Orange Drop PS series.

I'll offer these two threads for consideration:

1. Some of us on the Hoffman forum are making something of a collaborative effort to compare capacitors and tone. I think this is an interesting thread to read :

http://el34world.com/Forum/index.php?topic=19534.0

Note in reply #2 of the thread there is a comment about the Jupiter yellow caps being similar to the Orange Drop 225 which has been reported to be the "same" cap as the Orange Drop PS. (I do not know if that is correct?)

2. This thread has some observations that I've made using Musicaps in a
D'Mars ODS build of mine.

http://ampgarage.com/forum/viewtopic.php?t=28722

I do NOT think I would want an entire D-inspired build to have Musicaps as I think they would be too transparent? And the Musicaps are very expensive.

I found out this weekend that the Musicaps are so transparent that I can use a larger size coupling cap in between stages in the overdrive section in the D'Mars. For example the normally .01 cap after the first gain stage in the overdrive is now .02 with NO grit/buzz/fizz in the overdrive. In fact, this is the smoothest overdrive I've gotten out of any amp I've built.

In the past, when I've tried increasing coupling caps in the overdrive channel, it just made the overdrive sound too gritty/buzzy/fizzy for my tastes and I would revert back to HAD's values.

Just adding some thoughts for consideration as this is obviously a very subjective area of tone.

With respect, 10thtx

[Mr. dB]

1. Some of us on the Hoffman forum are making something of a collaborative effort to compare capacitors and tone. I think this is an interesting thread to read :

http://el34world.com/Forum/index.php?topic=19534.0

Note in reply #2 of the thread there is a comment about the Jupiter yellow caps being similar to the Orange Drop 225 which has been reported to be the "same" cap as the Orange Drop PS. (I do not know if that is correct?)

If I may, I'd suggest trying WIMA MKP4 or MKP10 caps, or if you can find them in the desired values, WIMA FKP stacked film-n-foil.

[Bombacaototal]

For higher plates (ie 221k) are you still using rn65d with 1/2W rating?

For 100k plate load the rn65d 1/2Wseems to be the consensus

[metalguy]

Note in reply #2 of the thread there is a comment about the Jupiter yellow caps being similar to the Orange Drop 225 which has been reported to be the "same" cap as the Orange Drop PS. (I do not know if that is correct?)

Wasn't there a thread where somebody from the factory confirmed that 6PS were in fact 418P?

If I may, I'd suggest trying WIMA MKP4 or MKP10 caps, or if you can find them in the desired values, WIMA FKP stacked film-n-foil.

Note that those two types are polypropylene caps. MKS4 are polyester.

[Mr. dB]

If I may, I'd suggest trying WIMA MKP4 or MKP10 caps, or if you can find them in the desired values, WIMA FKP stacked film-n-foil.

Note that those two types are polypropylene caps. MKS4 are polyester.

Yeah, that's why I was proposing them for the "collaborative effort to compare capacitors and tone". My experience with them in stereo equipment is that they are "hifi but friendly" sounding, and I wonder if that might be compatible with D-style amps?

[lovetone]

The Musicaps I found for sale are high values for xovers does anyone know where you can buy the values used in amps?