Many Benchmark customers are using their AHB2 power amplifiers with REL subwoofers. This application note shows how to connect one or two AHB2 amplifiers to one or two REL subwoofers using the speaker outputs on the back of the AHB2 amplifiers.
The MODE switch in the lower right-hand corner sets the AHB2 to stereo or mono mode. In stereo mode, the outputs of the AHB2 are conventional unbalanced outputs. In mono mode, the output of the ABH2 is balanced.
The two red binding posts (1+ and 2+) on the AHB2 are driven by the amplifier outputs. The black terminals (1- and 2-) are the ground returns for each of the two channels. We will use one of these speaker ground returns as a connection point for the REL ground wire. Notice that the SpeakON connectors provide access to the same set of outputs. In stereo mode, the left speaker is connected between 1+ and 1- using the binding posts or the SpeakON connectors. The right speaker is connected between 2+ and 2-.
Notice that the 1+ post is labeled M+ and the 2+ post is labeled M-. These are the outputs for mono operation. The speaker is connected between M+ and M- using either the binding posts or the SpeakON connectors. In mono mode, M- is an inverted version of M+.
REL supplies a cable with yellow, red and black wires that connect to the speaker output terminals on a power amplifier. The SpeakON connector plugs into the back of the REL subwoofer. The yellow and red wires deliver speaker-level inputs to the REL, but draw no power from the amplifier. The black wire is a signal ground reference for the speaker inputs. The yellow and red inputs are summed together in the REL. This summing allows the input of a left and right channel which will be summed to a single subwoofer. The yellow, red and black spade terminals will need to be connected to the binding posts on the back of the AHB2 power amplifier. We recommend connecting your speakers to the SpeakON connectors on the back of the AHB2 while reserving the binding posts for the REL cable.
Please read these instructions carefully because the yellow, red and black connection assignments will vary according to one of the following system configurations:
Caution: Never connect the REL BLACK wire to a RED binding post on the AHB2. This will short the output of the AHB2 ground and put it into protection mode. It could also damage the REL subwoofer.
Adjust the level of the REL subwoofer by turning the control on the back of the unit.
https://rel.net/how-to-connect-my-rel/
I asked ChatGPT to review the Benchmark AHB2, and I was shocked at the results!
It turns out that ChatGPT wrote a review by gleaning information from the many publicly available reviews of the AHB2. I recognized phases and sequences of words that had appeared in prior reviews, and yet the text was new, original, and well written. The ChatGPT review seemed to summarize the collective impressions of the reviewers without directly quoting any particular reviewer.
It should be possible to ask ChatGPT to write a review on any well-known product and the results may be an AI-generated review that reflects the collective opinions of many human reviewers.
Try this the next time you a planning to make a purchase online. These AI-generated reviews may be more useful than traditional search results. In essence, the search results are combined into a single well-written review.
It is also possible that ChatGPT is biased to give glowing reviews, so use caution! Try it out and have some fun experimenting with this new technology!
John Siau:
Write a review of the Benchmark AHB2 complete with listening impressions.
ChatGPT:
Title: Unleashing Sonic Purity: A Review of the Benchmark AHB2 Amplifier
Introduction: The Benchmark AHB2 amplifier has gained a reputation for its exceptional audio performance and unwavering dedication to sonic purity. In this review, we delve into the heart of this powerhouse amplifier, exploring its features, design, and most importantly, the listening impressions it evokes...
Today, Benchmark's John Siau and OpenAI's ChatGPT had a conversation about star-quad cables. It turns out that ChatGPT got quite a few things wrong, but learned quickly when these errors were pointed out by John Siau.
ChatGPT is quick to recognize mistakes, and quick to provide detailed corrections. In each of the first few corrections, additional errors were made. As each of these were pointed out, ChatGPT began to provide accurate information.
John Siau:
How do star-quad cables reject interference?
ChatGPT:
Star-quad cables are designed to provide improved rejection of ...
If an audio system is composed of multiple components, we may have detailed specifications for each component, but we will not know the performance of the combined system without doing some calculations. You may have questions such as these:
Use Benchmark's online audio calculators to find answers!
For example, if we know the output power of an amplifier, as well as the sensitivity and impedance of our loudspeakers, we can calculate the maximum sound pressure level that our system can produce.
This application note provides interactive examples that help to answer the questions listed above.