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Justjon
23-03-2016, 18:26
So, this was delivered today..

http://i261.photobucket.com/albums/ii52/micared/Tubebox_zps3mdfptok.jpg (http://s261.photobucket.com/user/micared/media/Tubebox_zps3mdfptok.jpg.html)

Question is, is there an idiot proof guide for setting the thing up to match whatever cart i buy next? It's currently set up to a 2M Red as i don't know any better :scratch:
And whilst on the subject of a new cart..
I’m using a OM10 at the moment, which obviously isn’t the best but I do have a budget of £150ish to replace it. My first thought was a 2M Blue or is there something else out there that i should consider? (TT is a Debut carbon for now).
Thanks :)

daytona600
23-03-2016, 19:17
http://project-audio.com/inhalt/en/manual/manual_tubeboxs.pdf
project manual
dip switches on the bottom to adjust the loading

hifi_dave
24-03-2016, 16:47
If you are looking for a 2M Blue, Radlett Audio can save you money..:thumbsup:

Justjon
24-03-2016, 19:49
dip switches on the bottom to adjust the loading
Thanks, but you may have just posted that in Swahili for all I understand :scratch:
I guess my question should have been about what, why and how :)

Thanks Dave, I'll be in touch for a 2M Blue

Firebottle
25-03-2016, 07:35
Hi Jon, I'll try and point you in the right direction.

The dip (dual in-line package) switches select either resistance, for the input impedance loading; capacitance, for the input capacitive loading; or the gain to suit MM or MC cartridges.
When the small knob of each switch is in the upward position, shown as ON at the side of the switches, the particular loading is switched into circuit.

INPUT IMPEDANCE
The first four switches alter this, but to slightly confuse - the resistance when all 4 switches are OFF is 47K, in other words a default value.

MM cartridges use 47K as the standard loading, so switches 1-4 OFF for any MM cartridge.

MC cartridges vary in their best loading, although the most common loading is 100 ohms. That would be switch 2 ON only. Consult MC specification for best choice.

INPUT CAPACITANCE
This has no effect on MC carts so is only applicable to MM carts. Additional capacitance with MM carts can tame any brightness that may be present. 150pF is a good choice as a typical value.

Switches 5 & 6 work by adding capacitance from a base starting value of 50pF. Switch 5 adds another 100pF and switch 6 adds another 200pF.

INPUT GAIN
Switches 7 & 8 are switched ON to reduce the gain from the default value of 61dB.

61dB is a typical gain figure for MC (low output) carts.
41dB with switch 8 ON is a typical gain figure for MM carts.

Hope this helps, :)

Justjon
25-03-2016, 14:12
Alan, thank you very much!
That's exactly the kind of explanation I was looking for. Just perfect :)
I like how this forum caters for the educated and also for the likes of myself :whistle:
Thanks again