Now I'm starting to get it

Easy Runnin

I just picked up a B&K EX-442 amp and MC-101preamp. They're in really good shape except for a couple minor issues with the preamp. The light doesn't work on the power switch, a plastic cover is missing from where the optional balanced output would be located, and there are no feet on the bottom. DC offset is 5.0 on the right and 1.2 on the left. This is a big improvement over the NAD setup. I'm sitting here listing to Bob James All Around Town and it's pretty amazing. The separation and clarity between the various instruments is awesome. I've listened to this CD hundreds of times but this is the first time I've heard it like this. Wow!

Any advise on where to get a lighted switch? Can I just replace a bulb or can the switch be easily replaced? Also what about some feet? Can I just go to Home Depot and get some stick on things or it there something better?

I also need to figure out the phono setup. But that for another day. Right know I'm just going to sit back, put up my feet and close my eye for awhile.

F1nut

Congrats on the new gear and starting to get it.

You'll have to pop the cover to see if the light is an LED or incandescent.

Look online for audio feet or use isolation devices.

Easy Runnin

So the phone stage on the preamp has the capability to set the resistive and capacitive loading for the phono cartridge. It's currently configured for a MM stage with a resistive loading of 50k ohms and no capacitor loaded (factory defaults). I picked up a new AT120E/T. load impedance is 47k ohms, recommended load capacitance is 100-200 pF.

Per the manual:

Cload = Ccartridge - Cphono cables - 75pF

Inserted R value = (100,000 * cartridge R value) / (100,000 - cartridge R value)

= 88.7k ohms vs 100k ohms (factory installed)

I'm assuming resistance and capacitance is close enough. Do those who really know agree?

I'm listening to Neil Young as I type this and it sounds really good to me

BKphoto

yeah I also became a B&K fanboy...didn't take long...

doctor r

Normally for a Moving Magnet cartridge the load impedance is 47K and variation is not as important for the sound quality as capacitance. The opposite is true for a Moving Coil with the critical match being the impedance and capacitance changes have a much smaller, if any, effect on the sound quality. What is the capacitance of your TT cables? Put the resistive load back to 50K (and we can increase some if needed to tame some high frequencies after you have the correct capacitance.) Many TT cables area around 200 pF so you may not need to change it, but that is where we start with a MM cartridge.

Easy Runnin

“What is the capacitance of your TT cables?”

I do not know how to actually do that, but I do have a meter with a “cap” setting.

The resistive load is at 50K. According to the calculation in the manual a 100K resistor is required for a 50K load:

Inserted R value = (100,000 * cartridge R value) / (100,000 - cartridge R value)
100,000 = (100,000 * 50,000) / (100,000 – 50,000)

Therefore a a 47k load requires a R value of 88.679K

doctor r

If your TT has captive interconnects the specifications may be available for reference by researching your turntable specifications (vinylengine.com). If they are loose cables again it may be published depending on mfg. I know they can be measured, but I have never had the proper equipment. I don't think you are off base in your setup, but part of this hobby is learning and trying to improve where we reasonably can. A pretty good overview of all the issues with illustrative graphs can be found at:
http://sound.westhost.com/articles/cartridge-loading.html
Enjoy you vinyl!

Rick

PS. Love the Monitor 7s. Still have my pair bought new in '79.

BKphoto

wow, that will suck the fun right out of listening to music...