What are these tubes

[thefatcyclist]

Friend of mine just bought a 50W Roost amp. the tubes are as follows.
1 x Edicron ECC83
2 x PM ECC83
1 x unknown ECC83...?
2 x Edicron EL34

Anyone know anything about these brands.

Amp is very like a Hiwatt, trannies are either Partridge or a vompany called electro voice (not the pa company) who apparently made Partgide clones, Partial tag and pcb board. Electrolytics are PYE
Cannot dee date codes anywhere including pots, but mid 70s ?

[OldSchoolDave]

the tubes are as follows.
1 x Edicron ECC83
2 x PM ECC83
1 x unknown ECC83...?
2 x Edicron EL34

Anyone know anything about these brands.

See: http://www.nostubestore.com/2010/03/ei- ... ecc83.html

Edicrons are good, pre-civil war era tubes.

As to the PM, does it look like this?: http://www.andertons.co.uk/valves/pid25 ... single.asp

No experience with those.

Dave

[thefatcyclist]

Thanks for the info dave.

The PM tube is like the one at the rear in the anderton ad with the blue print.

Cheers

[OldSchoolDave]

The PM tube is like the one at the rear in the anderton ad with the blue print.

I'm surmising that PM is a sorter / relabeler of tubes, not a manufacturer. As such, it's difficult to make blanket statements about their characteristics. How does the amp sound?

Dave

[thefatcyclist]

No idea, because the thing was completely dead so he got it for a very low price. Lucky bounder because all that was wrong was the main fuse was not connecting at both ends, slight adjustment and into life she went. Tech spent a day checking it out and he got it back today, but was prevented from playing it due to domestic stuff.
He is trying to find out if the roost has the same layout as the Hiwatts, so he can tube it like one if you know what I mean, but that is proving a bit problematic, that way we will see if it matches a Hiwatt in any way shape or form. I will report back. Problem is one of the main experts is a man who is not very well thought of by somebody on this forum, and if that is the case we do not want any contact with him either.

[mhuss]

The Roost amp pictures I have seen have very different layouts than our favorite HIWATTs. There were a number of amps, some very good, that were fitted with Partridge transformers, but but had little in common other than that with the HIWATT amps. However, the Roost amps had a lot of similarities -- Hiwatt style tones stack and PI configuration in particular, so it will be interesting to see how it sounds. Based on the pix and schematic Cailean sent, it looks like the preamp tube order is even the same (1,2,4,3).

(Post edited after looking over pix )

--mark

[hohohiwatter]

the roost 50w and 100w heads, if u can find them are quite hiwattish in both looks and sound, so not bad!

those pm valves arnt that great and every amp i've picked up 2nd hand with them in i've had to replace them so i think they are rubbish.