High plates non-HRm and Bluesmaster/HRM resistors type (183)

[mojotom]

So far I've build a low plate non-HRM and a 70's, awesome amps.
I'm going to start a 183 based amp. I'm a bit worried about what high plates will sound like but I like a couple of things in this amp from the start (EL34, no LNFB and small snubbers).

I don't know what resistors type and brand to use. These amps seems to use metal film almost everywhere but as I didn't want to mess the amp.
I need your advise.

So far I could use :

- Classic recipe with RN65 plates, 1% MF cathodes and carbon film everywhere else like the 124, sound nice to me so I even use that with some carbon comp on the 70's and like it a lot.

- 183 recipe using big 1w metal film (but didn't know the brand/type to choose, I read here some use Vishay CCF60).

- Fancy recipe, if metal film sounds good why not move a step forward and use AN tantalum resistors, a nice not harsh hifi resistors I could buy a couple of blocks near home.


I'm searching for a solid core shielded wire like the white one everyone use.

Thanks. Amazing forum !!

Tom

[David Root]

Tantalum resistors would be interesting, but big $$$!

I have most recently used RN65s on plate and cathode, V1, V2, and Takman carbon films on the PI plates.

I did the same on my '70s ODS and used carbon comps on the ODS entrance and V2 generally, same as Tony did, and it works well. NO snubbers! (But I used old iron).

BTW I may take out the 1M2 in the OD entrance and replace it with a 500K pot on the back of the chassis, to increase gain (thanx to Tony for that suggestion).

In metal films I also like PRP, either GP or PR9372. Can't tell the difference in MI amp use, (9372 is audio grade hi-fi stuff)

[hitchcaster]

i never liked the AN resistors in any application ive tried them in.... im sure you could find a good use for them but definitely no bang for the buck with those...

[mojotom]

Thanks David, I will order some to try. I've got PRP in my old Fender SReverb and it sounds amazing.

Hitchcaster, could you explain a bit what you found and where you tried them ? I've been using them in the feedback loop for now with good results.
In fact i build an Express in 2006 first with Bradley carbon comp then switched to AN then switched to Carbon Film. The carbon comp and AN seems to be the best but I've got a bit less details with the carbon film, a good thing for an Express. Never used them on others amps.

Tom

[ampdork]

NTE flamproofs 1W are the blue one in 183. Check Newark.

That said I am unsure f the composition has changed over time or not.

They are listed as metal oxide film in some place and just metal film in others...

CA uses tants for cathodes.