Seeking assistance with old Klipsch subwoofer that had its "power base" removed

[cyberdogg]

I found this old (early 90's) walnut subwoofer Klipsch SW-12 (with dual 12" driver on both sides) through the local classified ad last year. The (relatively wealthy) seller also included the subwoofer amp as a bonus. He was going to sell to me for a hundred bucks but decided to give it away for free. He included NHT SA-1 which is a subwoofer amplifier.

The problem is, the seller (or somebody before him) removed the internal power amplifier at the back of the subwoofer. However, the seller demo'd it to me using the subwoofer amp connected to a stereo receiver that played a LP album with the drivers beating and booming as functional.

I've been holding this subwoofer and its accompanying subwoofer amp for some time.

I bought "RCA Plug to Speaker Wire Adapter" [see diagram picture of NHT SA-1 amp below].

I bought "RCA Y-Adapter; 1 RCA Male to 2 RCA Male Y Splitter" but had to return it for a refund. I kept "RCA Plug to Speaker Wire Adapter."

Given that the power amp has been removed from the subwoofer, that makes the subwoofer passive, does it need a sophisticated stereo receiver or A/V to configure to play 'LFE' (low-frequency effect -- subwoofer sound) effects from the movie soundtrack?

Longer rephrased question: How do I connect the subwoofer to the subwoofer amp that's connected to UHD Bluray player (Panasonic DP-UB820 -- price rose because of U.S. tariff) with subwoofer port out using the suggested cable products described above, or do I need a separate A/V receiver, configured with subwoofer amp as connected, to be able to make the passive subwoofer function while watching the movie play on tv, instead of a stereo receiver that's for the LP/cassette tape/CD player?

Sorry for being a n00b.

I have no experience dealing with passive subwoofer. I had owned a powered subwoofer (Velodyne brand) with a Sony A/V receiver 25-some years ago. Storm surge killed my old system so I learned the importance of buying a power strip that prevents storm surge.

Here are the pictures and information if it helps for a solution (connecting to UHD Bluray player with subwoofer out port).

Subwoofer: Klipsch SW-12 manual

Subwoofer power amplifier: NHT SA-1 (but not with its accompanying model subwoofer included as omitted)

Picture 1 - front of Klipsch SW-12

Picture 2 - back of Klipsch SW-12 - with the hole of a removed power amplifier with the attached speaker cable consisting of black and red end points (by prior seller)

Picture 3 - example of an intact Klipsch SW-12 with the internal power amplifier (sourced from Reverb ended listing)

Picture 4 - front of NHT SA-1 subwoofer power amp

Picture 5 - back of NHT SA-1 subwoofer power amp

Scan of page 4 manual for rear of NHT SA-1

Picture 6 - Panasonic UHD Player with subwoofer port (audio out)

 

[Trebdp83]

If the Panasonic 7.1 analog outputs are selected for audio output, the HDMI port will no longer output audio.

A multichannel AVP/AVR with multiple HDMI input ports and one or more subwoofer pre outs will be best suited for the job here. Though, an AVP will require more amps.

At least two other speakers will need to be connected as the Front Left and Right speakers when using an AVP/AVR.

A single cable from an AVP/AVR subwoofer pre out is all that is really necessary to connect to the NHT RCA L or R input. Though, you can use a Y adapter to split it into both the L and R ports.

Now, if a Stereo receiver is present for LP and CD as mentioned, you can connect the Panasonic to it using L and R RCA cables assuming it has no digital ports. Set the Panasonic to output 2ch Downmix. This will also result in the HDMI port outputting a video signal but no audio signal.

Then, connect the speaker cables from the receiver’s speaker terminals to the NHT’s “FROM AMPLIFIER” terminals. Connect the NHT’s “TO SATELLITES” terminals to your speakers. Connect the Klipsch subwoofer to the NHT’s “SUBWOOFER OUTPUT” terminals. Adjust the crossover to your liking. Be aware that the NHT has a high pass filter and the low end will not be output from the Mains and the crossover may be best set from 80 to 120. Good luck with it.

 

[TLS Guy]

I found this old (early 90's) walnut subwoofer Klipsch SW-12 (with dual 12" driver on both sides) through the local classified ad last year. The (relatively wealthy) seller also included the subwoofer amp as a bonus. He was going to sell to me for a hundred bucks but decided to give it away for free. He included NHT SA-1 which is a subwoofer amplifier.

The problem is, the seller (or somebody before him) removed the internal power amplifier at the back of the subwoofer. However, the seller demo'd it to me using the subwoofer amp connected to a stereo receiver that played a LP album with the drivers beating and booming as functional.

I've been holding this subwoofer and its accompanying subwoofer amp for some time.

I bought "RCA Plug to Speaker Wire Adapter" [see diagram picture of NHT SA-1 amp below].

I bought "RCA Y-Adapter; 1 RCA Male to 2 RCA Male Y Splitter" but had to return it for a refund. I kept "RCA Plug to Speaker Wire Adapter."

Given that the power amp has been removed from the subwoofer, that makes the subwoofer passive, does it need a sophisticated stereo receiver or A/V to configure to play 'LFE' (low-frequency effect -- subwoofer sound) effects from the movie soundtrack?

Longer rephrased question: How do I connect the subwoofer to the subwoofer amp that's connected to UHD Bluray player (Panasonic DP-UB820 -- price rose because of U.S. tariff) with subwoofer port out using the suggested cable products described above, or do I need a separate A/V receiver, configured with subwoofer amp as connected, to be able to make the passive subwoofer function while watching the movie play on tv, instead of a stereo receiver that's for the LP/cassette tape/CD player?

Sorry for being a n00b.

I have no experience dealing with passive subwoofer. I had owned a powered subwoofer (Velodyne brand) with a Sony A/V receiver 25-some years ago. Storm surge killed my old system so I learned the importance of buying a power strip that prevents storm surge.

Here are the pictures and information if it helps for a solution (connecting to UHD Bluray player with subwoofer out port).

Subwoofer: Klipsch SW-12 manual

Subwoofer power amplifier: NHT SA-1 (but not with its accompanying model subwoofer included as omitted)

Picture 1 - front of Klipsch SW-12

View attachment 74696

Picture 2 - back of Klipsch SW-12 - with the hole of a removed power amplifier with the attached speaker cable consisting of black and red end points (by prior seller)

View attachment 74697

Picture 3 - example of an intact Klipsch SW-12 with the internal power amplifier (sourced from Reverb ended listing)

View attachment 74703


Picture 4 - front of NHT SA-1 subwoofer power amp

View attachment 74698

Picture 5 - back of NHT SA-1 subwoofer power amp

View attachment 74699

Scan of page 4 manual for rear of NHT SA-1

View attachment 74702

Picture 6 - Panasonic UHD Player with subwoofer port (audio out)

View attachment 74701

That sub is from 1993, and not that good then. It took me a while to find information on it. That sub only has one loudspeaker driver. The other driver is a passive bass radiator, which is a driver with no magnet or voice coil. They are known as ABRs. It takes the place of a port on a typical ported sub.

Now what you need is a plate amp, and you must close off the space where the previous sub amp was.

That was never a very good sub even by 1993 standards apparently, so you don't want to put a lot of money in it. To be honest that unit is close to junk, if not already at that state.

Here is the a cheap and cheerful plate amp, that will get you in business. So you need to mount that in your sub with no air leaks and then you need to close off that opening where the old amp went with no air leaks.

You will need to connect the one active driver to the plate amp, before screwing it in and sealing it.

If you don't have the carpentry skills to accomplish this, then sell it, or send it to the recycling center.

 

[Trebdp83]

Or, just try it out with what you have at no additional cost to you. Stuff something in the hole to seal it off. If you could stuff a hole that size with a chunk of ego and hot air, @TLS Guy would be the first person I’d call as he has much to spare.

 

[TLS Guy]

Or, just try it out with what you have at no additional cost to you. Stuff something in the hole to seal it off. If you could stuff a hole that size with a chunk of ego and hot air, @TLS Guy would be the first person I’d call as he has much to spare.

I gave him the correct advice, that will actually return his sub to original audio condition.

Your advice is totally useless. You accuse me of hot air, but your post is wasted breath.