If I build it, will it work?

[Mysteriphys]

hey everyone, I've trolled here as a guest quite a bit. I'm still grasping straws as far as my understanding of the actual circuitry building and such, but I've been doing a lot of reading and poking around.

basicly I'm looking to build myself a solid state *bass* amp, I have 2 aged tape decks, a home amp, all from the 70's I've gutted one of the tape decks for resistors transistors, and diodes and the rest. I have an alpine 10" subwoofer 4 ohm in a box (or the typical 2X 8" woofer + tweeter from that era in house cabinets) my first question is.

if I want to keep my amp in 1 piece, is it possible to turn the tapedeck that I haven't gutted into a pre-amp, and have the correct input voltages and output ohms to match 1 or both of my speaker setups, noting that the sub-bass levels may ruin my house speakers.

#2 if I wanted to go all out, knowing that I have opamp chips, ages old transformers, and tons of other goodies. is it possible to rip apart the home amp and build something relatively clean sounding out of all the parts I have from the 2 decks and amp. ( also the amp has a cold start problem, I have to heat the thing up with a hair dryer to get it going >.<)

to a point from what I've read, I'm probably heading for the inevitable "just buy one" response in order to have something to learn from or just use and be happy with. but I'm very hands on, and I really want to be able to adjust things that aren't adjustable on normal amps, I dunno how much sense that makes, but I'm an Electrojunkie newb, I have 3 circuit bent keyboards, 2 home-made preamps from spare parts and online diagrams *the Ruby style setup with adjustments* and I want to understand more.

I really hope this isn't another "repost that should have searched" situations, but I figured given the fact that I have a few pieces and bits around that might be helpful that I may be taking the whole "newbie" thing in a different direction.

[J M Fahey]

If you tear the amp apart, probably all you will be able to use is the power transformer, if anything.
If the amp still works, check that it can drive 4 ohm loads per channel, then you can hook both hi fi cabinets to one channel, the 4 ohm 10" subwoofer to the other, that should provide a reasonable volume for home practice or light garage rehearsal duty.
You could build a simple 1 transistor preamp to pick up your bass signal and send it to both line in (RCA?) jacks.

[Mysteriphys]

If you tear the amp apart, probably all you will be able to use is the power transformer, if anything.

I'll keep that in one piece then, I may have to find some replacement transistors though, I did a little home brew troubleshooting and it seems to only start once I heat up the heatsink. everything else internally seems to be doing it's job.

If the amp still works, check that it can drive 4 ohm loads per channel, then you can hook both hi fi cabinets to one channel, the 4 ohm 10" subwoofer to the other, that should provide a reasonable volume for home practice or light garage rehearsal duty.

Check, it's built for 8 ohm but says it handles 4 ohm as well.

You could build a simple 1 transistor preamp to pick up your bass signal and send it to both line in (RCA?) jacks.

it would be rca Out to the amp for sure, I just figured it would be fun to complicate things and place it in-line somewhere in the tape-deck's and have it on mains power (I have a transformer from the tape deck I gutted, and the other tape deck still powers on with the actual tape part clipped out, it also has a stereo input Levels pot (with digital display) built in which is why I was thinking of using that, I also have analog displays and stereo linear pots that I could build my own with seperately if I really wanted to. but I kind of like the idea of having the possibility of adding in an in-line pre-preamp delay loop. but that just my eager inner electrofreek talking :-P.

but if you think the little gem setup would be easier I can deal with that.

[J M Fahey]

The little Gem will be easier and with a regular pot (5K to 100K, preferably audio taper) on its output, can work as a preamp and even provide distortion, good idea.

[Mysteriphys]

Hey I'm now tearing down the second tape deck (poineer ct F555), after a little research I found out the Transformer in it was made by a company that was bought out in the late 70's, it looks really neat though, kind of like a showpeice model, HATA Radio co,. LTD model: M482, other ID on it stickered "RTT - 222 (o-at-aht)"

it has 11 pins 8 of which are in use, 2&3 for the AC input on one side, and the 6 on the other are pairs of green, blue, and red,

I'm trying to get my basic understanding of these Transformers, so any assistance would be greatly appreciacted.

I think once I can understand the ideals of transformers I can brain up a bit and finally get a handle on things

[Mysteriphys]

Also, Tape Deck is equipped with HA12006 and HA12005 chips, it looks like I would be able to build a decent circuit off the HA12006.

Am I barking up the wrong tree here? or is this viable with work.