How to Convert Tape Head Output to Line Level Input?

[Philcoradio]

Hey all,

I have an old Viking 4 Track/Fidelipac Player that I’d like to hook up into my stereo system. The Viking player has a built in amplifier with speaker outputs, but unfortunately one channel is dead in the amp. I figured I’d just take the RCA outputs from the tape head and try to convert that level to a line level. Unfortunately I ran into a snag because I can’t find any info on how to do this properly. My pre-amp doesn’t have a tape head input on the back (A McIntosh C33, if it makes a difference) and even though my spare pre-amp (Dynaco PAT4) does have a tape head input, it sounds quiet and a little on “bright” side. Does anyone have any suggestions on how I should go about this? Any help is greatly appreciated.
Thank you,
Chris

 

[DesertRatt]

"Take Head" inputs on older preamps are a bit like phono inputs. They need lots of gain and some equalization settings.

Circuits exist in texts like "Radiotron Designers Handbook". Do a Google search for tape head amplifier. Or get the schematic for an old Scott receiver.

 

[DesertRatt]

Here's an easy to build tape head amp with all the proper EQs for NAB,

http://www.seekic.com/circuit_diagram/Amplifier_Circuit/FOUR_SPEED_PLAYBACK_PREAMP.html

 

[Okke 70s]

What you seek to do with your Viking, is to use it as a "transport". Basically a machine to transport the tape along the head, and nothing more. As DesertRatt explained, you need a tape head amp between the head and the line-in of your amplifier. If only just to experiment, you could use the one of any other RTR. Just hook up the wires from the head of your Viking instead of the wires from your "amp" RTR's head. Run a tape on the Viking, put the "amp" RTR in "play" mode, and it should have sound at its output.

 

[twiiii]

What you really need is a restored Mcintosh C-20, with the tape head input and different equalization curves to get the best sound. C-22 might work too as it has a special EQ setting for tape head. Shure use to make a stand alone little tube pre-amp with MM and tape head inputs. that worked fairly well. SHURE M65.

 

[Philcoradio]

Thanks for all the replies. I am probably going just seek out a stand alone tape head pre-amp. If I can’t find any, I have a couple of cassette decks that I could use parts from and get something working. And unfortunately looking for a McIntosh C20 or C22 isn’t the most economical thing at the moment. Thanks for all the help everyone!

 

[62vauxhall]

This made me wonder if a tape head connected to a phono input would work?

I don't know what voltage a tape playback head produces, but if it's too low for an MM input, then maybe an MC input (if available) would be compatible?. If so, then a stand alone phono pre-amp (either MM or MC) might be a cost effective way to connect a tape playback head to an amplifier's line input. .

EDIT: I have and old "black box" inline phono pre-amp kicking around. If this situation occurred to me, I would certainly try using it. There's nothing to lose.

 

[WizardWG4]

It is possible to modify the eq feedback network on an opamp phono preamp to convert from RIAA to NAB. Search the LM833 datasheet for an example.