Pictures Of My Kit

[JimC]

.................the ef86 can be noisy, what have you done to reduce this, triode?
sometimes a shielded socket helps.

I have thought about a Shielded Socket but don't think i'd get much more improvement now.

I experimented with the way pins 2 & 7 were connected, to zero Volts seems to have produced better results over connecting to the cathode.
I have also increased the Cathode resistor value. This has had the effect of reducing overall stage Gain which therefore 'masks' any noise. This i have found has worked extremely well and i still get 'room filling sound' with a 1KOhm there instead of what Mullard quote for the 3-3 (upon which the circuit is based).

I think maybe 'next time i would have the 86's slightly physically farther away from the GZ33, though as i say, things as they stand, there is very little noise/hum. One has to place ones ear right up against the speaker to hear any. From my listening position i cannot hear anything whatsoever with the Amp idling. I am very pleased.

Thaks for all the nice comments folks,

James.

[RochaCullen]

Hi James,

I also use a DL-304 with an R-200. Tell me, do you need to do much fettling before the arm and cartridge perform to a good standard? I ask because, other than rewiring the arm, I have not done much to try and marry the two.

Regards,

Nathan

[Alex_UK]

Very, very nice - must be so satisfying to know you contributed so much time and effort to the system, rather than just bung a few boxes together like I have! Maybe, when I have more time... hmmmm...

[John]

Nice work looks really good

[JimC]

Hi James,

I also use a DL-304 with an R-200. Tell me, do you need to do much fettling before the arm and cartridge perform to a good standard?.........

No, just 'Plug and Play' worked for me. The Tracking weight is, i have found, very critical and does affect the sound greatly. Once set for the Manufacturers specification, exactly, it sounds sublime.

My arm is as standard except for the connection at the bottom of the main stem. The 'Din' (for want of a better term) style connector and captive leads was faulty when i got the arm (second hand-the reason i was 'given' it) so i removed it and installed an actual 5-pin Din plug on to which i have attached 'cartridge' style connectors (removable) on a lead to the underside of a 4-pin XLR socket mounted on the plinth.

I will try and post some more pics of the T/T so you can see more clearly.

Cheers,

James.

[JimC]

Some Pics of my 845 Amp.

First experiments..................


Bought an incomplete box from a chap, needed two extra holes and one filling in. Tried a bit of Marquetry!!.......


Early Internals.......


Almost there, spot the deliberate mistake!!


And all done.....

[Puffin]

Very nice.

[Idlewithnodrive]

Looks lovely James.

How does it sound ?

[petrat]

Very, very nice! Rather inspirational, actually. Is it a home-brew design, or did you follow a published design?

[JimC]

.................How does it sound ?

Really rather good though I say so myself.

...................Is it a home-brew design, or did you follow a published design?

I started with this design..........................
http://tube-amps.net/How_Hashimoto_sounds.htm

but couldn't get it to sound as I wanted it to so ended up changing quite a bit.
I didn't like what C3 did to the sound so omitted it. I have to say it will not please the SET Purists as I have used Feedback permanently, not in a variable way as Mr. Matsunami did. I am afraid I am of the school that has nothing against Feedback. The few tests I have done on SET's I have always felt it is the sound of the Output Transformer that the Purists must be liking. The Valve (SET) itself often has a ruler flat frequency response if measured at the Anode but by the time it has gone through the O/P TX it becomes ''an SET''. Let Feedback do its job and you hear what the Valve can do, in my humble opinion.
To compensate for the loss of Gain due to the Feedback I added another stage, outside the feedback loop actually, which also made the whole thing non-inverting too which bothered me slightly perhaps unnecessarily so but it did!

James