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Nightbrace
11-19-2005, 02:04 PM
I currently have a Concept 2QD turntable sold by Pacific stereo from 1978.
It is a direct drive, quartz lock unit. Not sure of the cartridge or needle, but I am sure it is probably what came with the unit originally.

What turntables in the $200 price range would be better than this unit?

Currently I use a Pioneer SX-737 with this turntable and the volume of the LP is much less, maybe 10 Db or so , compared to a CD with the same recording.

I am relatively unfamiliar with turntables, is this common for LP's to produce volume levels that much lower than a CD? Or could this be a problem with the turntable itself?

gerard
11-20-2005, 03:59 PM
I think first you have to know what is the cartridge you are using and also if the setup is ok ( antiskating and weight ) .

The more improvment you can do may come from the cartridge / stylus unless your turntable does not work .

There is always a difference in volume between Cd and Lp , if the sound is good you simply turn the volume ; this is what I do !

gerard

mech986
11-20-2005, 07:10 PM
Hi NB,

Nice table! I've been looking for one of those to complete a small system of Concept components - currently have the 5.5 receiver (needs work) and the Concept ELC I and II cassette decks - all have a nice industrial design like a Late 70's Yamaha with American Muscle overtones.

Most turntables of that era would have a moving Iron/moving magnet (MM) type cartridge that has a typical output of about 5 mv nominal. The phono sections of 70's era recievers would boost them up to typical line levels of about 0.1 to 0.4 volts and then drive the line section (IIRC) which then drives the outputs.

The CD outputs of most contemporary models are usually set fairly hot - on the order of 0.5 to 3 volts - this is then connected to the receiver at the AUX input. Now the AUX input was usually supposed to hook up other lower output devices like another tape deck (cassette, 8-track, RTR) or other line level devices. So the CD will usually sound louder in volume simply due to the differences in nominal settings. That's always a problems (relative volume settings) because when you have everything hooked up, switching from a phono to a CD usually meant a blast of sound unless turned down.

Assuming the phono cartridge is working OK and all connections are fine, and the phono section is properly working, you might see if you can cut down the CD output to match levels of input with the phono. Many CD's will have a remote volume function that allows moderation of the otput signal. Then you can vary the whole system volume using just the reciever controls.

Now, if the cartridge is a moving coil, these give very low outputs -from 5 microvolts to about 2 mv for high output moving coils (MC) - note even the highest output is still about half of a typical moving magnet design. So these moving coil units require a pre-preamp to boost the signal high enough to go into a typical receiver. Some later receivers had a builtin moving coil input though. The 737 was an early 70's model so doesn't have a MC input.

So, important to try to identify the cartridge manufacturer and maybe the model number. Some pictures of the cartridge (macro setting on your digital camera) and table will help if possible to do. You might also post over to AudioKarma.org and see if they can help.

Regards,

Bart

Nightbrace
11-21-2005, 06:26 PM
thanks for the input, I guess maybe I should consider keeping it. I only have maybe 50 LP's so I don't use it often/ Would have any interest in this turntable to complete your system?? It is in great condition and as far as I know works perfectly. Please send me an email or a PM if you are interested.

jandregg
11-23-2005, 07:25 AM
Some 70's era receivers had internal pots to set the signal level of the varied inputs so that all produced a similar loudness. Some had access holes in the bottom so that it was unecessary to open the cover to set the levels.


John