Have Cool Equipment, Need Wiring Help

[Pik95]

A tuner is a stand-alone radio reception device. A receiver is a combination of a tuner section (in newer units internet connectivity as well), a pre-amp section and an amplifier section all in one box.....

So is my 8080DB an amplifier (like many old timers seem to call it) or a receiver? If a receiver has a phono spot does that mean it has a preamp inside?

 

[lovinthehd]

So is my 8080DB an amplifier (like many old timers seem to call it) or a receiver? If a receiver has a phono spot does that mean it has a preamp inside?

Brand and model number together help If it's a Sansui it appears to be a receiver. Calling it just an amp is vague, kinda like calling your car "wheels" . Amp alone is often thought to be just that...just an amplifier, or power amp. An integrated amp has a pre-amp and amp combined. A receiver adds the tuner/internet.

If there is a phono input it is generally an indication the unit has it's own built in phono stage (pre-amp & RIAA eq).

 

[BMXTRIX]

For your inquiry on your Marantz receiver.

If this is the back of it, then you can connect sources to it, just as you would with your ST-5 unit. I wouldn't use the Marantz over the Nakamichi necessarily. It has the added amplifier inside which you don't need. Not sure how the quality truly stacks up next to the Nakamichi as well.

But, it does have 'PRE OUT' connections that are labeled. That is what you use to connect to an amplifier. Those would be your 'PREvious to the amplifier OUTput' from the Marantz.

 

[BMXTRIX]

In most cases, if you have a pre-amp or a AV receiver which has a 'PHONO' input on it, then that product will have an integrated phono pre-amp built in. Record players (phonographs) do not have the typical line level RCA input feed that other equipment typically has. Like your Tuner, or a CD player. Those devices have a higher power level on their RCA connections. So, a phono input will raise the input level from a record player to have it properly match the levels which a normal product will put out.

From there, it can be properly passed on to an amplifier without any further fuss on your part. You just plug it in and forget about it.

This is also one of the reasons I would think the Nakamichi might outperform the Marantz. It is supposed to have a very good phono amplifier built into it.

 

[BMXTRIX]

Sorry for the multiple posts...
The Sunfire is absolutely the subwoofer I would use. Their build quality is incredibly high and their output far exceeds their cabinet size due to the sealed design and very high excursion that they offer.

From the Nakamichi you would connect:
CA-5 (output 2) - Left/Right into the Sunfire Inputs (line level) Left/Right

 

[Pogre]

Sorry for the multiple posts...
The Sunfire is absolutely the subwoofer I would use. Their build quality is incredibly high and their output far exceeds their cabinet size due to the sealed design and very high excursion that they offer.

From the Nakamichi you would connect:
CA-5 (output 2) - Left/Right into the Sunfire Inputs (line level) Left/Right

Yeah, I wasn't sure at first, but after a little research I realized that's a very capable little sub. It's my choice as well.

 

[Pik95]

For your inquiry on your Marantz receiver.

If this is the back of it, then you can connect sources to it, just as you would with your ST-5 unit. I wouldn't use the Marantz over the Nakamichi necessarily. It has the added amplifier inside which you don't need. Not sure how the quality truly stacks up next to the Nakamichi as well.

But, it does have 'PRE OUT' connections that are labeled. That is what you use to connect to an amplifier. Those would be your 'PREvious to the amplifier OUTput' from the Marantz.

That is the back, thanks. I assume it's just an aux that I put it into on the amp side. Or is it marantz preout (as a tuner) connected to the preamp? Other than that I got it. I'll try both, just to see which sounds better. The Naks power wire had a cut in it. I'll get it replaced but electric tape tonight to see. Wife is making me repaint the space before I wire it up. Hopefully I will have ut all ready for Bisco stream tonight. As always, thanks for the help!

 

[BMXTRIX]

Well, this is one

I assume it's just an aux that I put it into on the amp side. Or is it marantz preout (as a tuner) connected to the preamp?

See, this is why I like the Nakamichi. It has TWO sets of preouts on the back, while the Marantz only has one. Realistically, you should use RCA splitter cables with the Marantz. This way you can split the RCA audio output to both the amplifier (and your main speakers) and the other RCA connections would go to the subwoofer.

On the Nak, it already has two sets of preouts. One set would go to the amplifier, while pre-out 2 would go to the subwoofer.

All connections you make to the subwoofer should be using RCA connections, not speaker level/speaker wire connections. The subwoofer has a built-in amplifier that is already designed to work perfectly with it.

So, you would need something like this on the back of the Marantz to feed both the subwoofer and your amplifier...

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[Pik95]

Well, this is one

See, this is why I like the Nakamichi. It has TWO sets of preouts on the back, while the Marantz only has one. Realistically, you should use RCA splitter cables with the Marantz. This way you can split the RCA audio output to both the amplifier (and your main speakers) and the other RCA connections would go to the subwoofer.

On the Nak, it already has two sets of preouts. One set would go to the amplifier, while pre-out 2 would go to the subwoofer.

All connections you make to the subwoofer should be using RCA connections, not speaker level/speaker wire connections. The subwoofer has a built-in amplifier that is already designed to work perfectly with it.

So, you would need something like this on the back of the Marantz to feed both the subwoofer and your amplifier...

Amazon.com: iExcell 2 Pcs Blue Male to 2 Female RCA Speaker Splitter Shielding Cable Adapter: Electronics

Buy iExcell 2 Pcs Blue Male to 2 Female RCA Speaker Splitter Shielding Cable Adapter: RCA Cables - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

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I think my Marantz is a little underpowered to use it's amp though, right? That's where I get mixed up. I wouldn't use the Marantz amp and the B&K amp in the same setup, right? No need I'm thinking. Appreciate your time. Thanks
:edited to add: I can use the Marantz strictly as a tuner, right?

 

[lovinthehd]

I think my Marantz is a little underpowered to use it's amp though, right? That's where I get mixed up. I wouldn't use the Marantz amp and the B&K amp in the same setup, right? No need I'm thinking. Appreciate your time. Thanks
:edited to add: I can use the Marantz strictly as a tuner, right?

You can use the Marantz with the external B&K power amp, the Marantz would act as tuner/pre-amp. Or you could use the Nakamichi CA-5 as pre-amp (Nakamichi calls it a control amplifier which is a bit confusing I suppose) with the B&K power amp, but no radio tuner is included in the CA-5 (like the Marantz) but you could use the ST-7 for that part if you wanted.

Your Marantz is like 40wpc at 8 ohm, it might do okay, but since you have the much more powerful power amp the power amp is what I'd use (unless it's broken or something).

You have some duplication in gear which can be a good thing if you find something not working properly, you have alternatives....

 

[Pik95]

You are right. I purchased the Nak pre because of that phono that was mentioned before. The B&K amp is also highly regarded so I will use that also. Nak tape deck, Thorens 160, and Cal Audio HDCD. Sunfire Junior sub and Thiel 2.3 cs 4 ohm speakers rounds it out for now. The only question really is Nak tuner or the Marantz 2238B as strictly a tuner I believe. Thanks!

 

[lovinthehd]

I'd just use the Nak tuner.

 

[BMXTRIX]

You're getting a lot of call outs to simply not use the Marantz at this time. I agree with those call outs. For simplicity, use the NAK gear for everything. Skip the Marantz. Once you get it setup, and you play with things for a bit, then you may want to give the Marantz a try.

At least that's what I'd do at this time.

The NAK has two sets of pre-outs which is good for using both your speakers to the amplifier, and your subwoofer.

Hook up the NAK tuner, the record player, and any other RCA sources you would like to. I have a large 16 input pre-amp I use and it has my cable boxes, Blu-ray Disc player, Roku, and other gear hooked up to it. It's really enjoyable getting that much versatility. But, start with what you have, then go from there.

 

[Swerd]

Here is a picture of the back.

For what it's worth, your B&K ST2140 amp is pretty good. It's rated as delivering 140 watts/channel when driving an 8 ohm load and 185 watts/channel for 4 ohms, at 0.09% total harmonic distortion. It also delivers fairly high current, as high as 30 amperes per channel (measured from peak to peak).

The B&K amp is about 3½ times more powerful than your Marantz 2238b stereo receiver, which is rated at 38 watts/channel at 8 ohms. Note that it is not rated at 4 ohms.

I'd use the B&K to drive your Thiel speakers. Maybe you could sell the Marantz, as they seem to go for high prices for a used stereo receiver from the 70s.

You could also use the Marantz as a pre-amp while connecting to the external B&K amp to drive your speakers. But that arrangement doesn't do anything that your Nakamichi CA-5 pre-amp and ST-7 tuner can't do. It's only advantage would be that it has a built-in tuner and might take up less space.

B&K made the ST2140 amp from 2000-02. B&K also made a 3-channel amp, the ST3140, that probably used the same chassis as the 2-channel ST2140 that you have. That would explain the unused channel 2 in your photo.

B&K was an American company, located in Buffalo, NY. Unfortunately they are now out of business. But your amp is good and can be repaired if needed.

 

[Pik95]

For what it's worth, your B&K ST2140 amp is pretty good. It's rated as delivering 140 watts/channel when driving an 8 ohm load and 185 watts/channel for 4 ohms, at 0.09% total harmonic distortion. It also delivers fairly high current, as high as 30 amperes per channel (measured from peak to peak).

The B&K amp is about 3½ times more powerful than your Marantz 2238b stereo receiver, which is rated at 38 watts/channel at 8 ohms. Note that it is not rated at 4 ohms.

I'd use the B&K to drive your Thiel speakers. Maybe you could sell the Marantz, as they seem to go for high prices for a used stereo receiver from the 70s.

You could also use the Marantz as a pre-amp while connecting to the external B&K amp to drive your speakers. But that arrangement doesn't do anything that your Nakamichi CA-5 pre-amp and ST-7 tuner can't do. It's only advantage would be that it has a built-in tuner and might take up less space.

B&K made the ST2140 amp from 2000-02. B&K also made a 3-channel amp, the ST3140, that probably used the same chassis as the 2-channel ST2140 that you have. That would explain the unused channel 2 in your photo.

B&K was an American company, located in Buffalo, NY. Unfortunately they are now out of business. But your amp is good and can be repaired if needed.

Great post! Lots of good info. Thanks! I may just set up other room systems with my Marantz and Sansui (when I get it back). I am getting offered a dirty but decent looking Sansui 809DB with the Black face that I am considering grabbing too. I really have no good reason to get it though. This hobby is dangerous, lol.

On a side note, all of my giant speaker wire has turned green on the inside for some reason. I'm guessing I don't want to use that now...

 

[Swerd]

On a side note, all of my giant speaker wire has turned green on the inside for some reason. I'm guessing I don't want to use that now...

That green is only on the outer surface of the copper, where it meets the plastic insulation. The cheap Chinese made wires uses polyvinyl chloride plastic insulation, made by polymerizing vinyl chloride monomers. They probably skipped the step where they removed excess unpolymerized vinyl chloride, and it reacted with the copper wire. Consider that green layer as camouflage. It's harmless.

 

[Pik95]

That green is only on the outer surface of the copper, where it meets the plastic insulation. The cheap Chinese made wires uses polyvinyl chloride plastic insulation, made by polymerizing vinyl chloride monomers. They probably skipped the step where they removed excess unpolymerized vinyl chloride, and it reacted with the copper wire. Consider that green layer as camouflage. It's harmless.

But it's UGLY! LOL

 

[Swerd]

But it's UGLY! LOL

Reminds me of my favorite Rodney Dangerfield joke:

Last week was a rough week for me. I broke up with my psychiatrist. He told me I’m going crazy.​

​

I said to him, ‘If you don’t mind, I’d like a second opinion.’​

​

He said, ‘Alright, you’re ugly too.’”​

 

[Pik95]

Is it ok to mix and match different brand RCA cables from the preamp? I have this super long Monster cable 100 interlink. Not really sure what that would be for yet Subwoofer maybe? Then I have two pairs of these black cables where the tops are completely gold colored except for the red and white lines. I also have a monster set that says it's for CD. But I thought they were all the same. This wire business is confusing. Ill take a picture.

 

[Pik95]

Here are some choices. Are these ok to mix? I have more in the back of the garage I'll dig out. Thanks