BHK 250 with pair of REL T9i subs

I’m receiving my BHK 250 stereo sub today. I have two REL T9i subs that I want to connect using the high level Neutrik Speakon cables. The REL owners manual is not clear on how to connect the pair of subs to a balanced stereo amp. I’ve Googled for info, but so far can’t find a definitive answer. Does anyone here have experience connecting these subs? Obviously, I don’t want to experiment with such expensive gear. Thank you.

Welcome!

This REL setup guide may help: click

Yours is a very specific question however. Good luck!

gsevilla,

You will have to dedicate each of your REL T9/i subs to a channel. In other words, you will have a Left channel sub and a right channel sub.

You can combine the RED and YELLOW wires of the left REL high level cable at the Left positive speaker output on the BHK. Go ahead and twist them together. Do the same for the Right channel.

See attached PDF. You will essentially treat the connection as if it were two mono block amps which is what the PDF shows.

You CANNOT connect the BLACK wire of the REL high level cable to the negative speaker outputs.

The attached PDF shows the BLACK wires floating, which often works, and will work with the BHK during normal operation.

However, when the BHK is switched to stand-by the RELs will hum because they loose their ground reference.

PS and REL offer a kit to connect the BLACK wire of the REL high level cable to a point on the BHK chassis. This will reduce the hum from the RELs when the BHK goes to standby, but not completely.

At this time, the ultimate solution to eliminate this hum is to turn off the RELs when BHK is in standby.

That said, during normal operation, there are to problems or compromises with this setup.

Very best regards,

Justin

Chief Engineer

REL Acoustics

Thanks for the very helpful info and welcome to the forum! But I don’t see a PDF attachment. I’m not sure the site software allows for PDFs. If not, you might try a JPEG.

REL subwoofers are highly regarded around here.

Thank you, JustinM and Welcome!

To All,

Thanks for the warm welcome.

Let me try that file again.

I will be checking the PS forum periodically, so feel free to ask the REL guy questions.

Also, please feel free to drop me a line at contactus@rel.net for direct questions or help.

Justin

Thank you, Justin. The PDF came across perfectly.

As already mentioned, there is a lot of love here for REL so your presence here is a particular pleasure.

(And as the owner of multiple Ducatis, I appreciate anything two-wheeled Italian.)

I don’t have a REL at the moment but keep thinking about it. If I got one, it would be for my second system which will soon (shipped today!) be driven by my PS Audio Stellar M700 mono blocs. I assume the hook-up would be the same as in the diagram and it would be either a left or right subwoofer. Is that right?

Yup.

If you add a single sub playing only one channel I suggest it be the right. For pop, bass is typically centered; for classical, the bass is typically on the right (string basses, 'cellos, tuba, bass trombone, sit on audience right).

I’m wondering, with all due respect, why in the world would PSAudio not include a ground post on their amps? Even my little McIntosh MA5200 integrated has a ground post! I’ve asked for the grounding “kit”, but based on some comments in this forum, it doesn’t seem to work. So far, with this problem and the loud hiss others and I have mentioned, there are more ticks on the cons side. Don’t get me wrong, it sounds great so far, but I’m not blown away compared to my little Mac. The good thing, as Mr. McGowan mentioned, Amazon has a great return policy. By the way, the reason I decided to try out the BHK 250 is that I bought a DSj a few weeks ago. It made such a big improvent to the sound of my system that I was motivated to add the amp because I figured the synergy would be out of this world. Unfortunately, it’s the small (or not so small) details that are destroying the synergy. Oh, and to add another tick to the cons, I can’t get it out of my head that the Amazon discount was due to this amp being a “left over” from the first production run (based on its serial number). In other words, I don’t have the latest iteration of this potentially great sub. One tick on pros, four on cons. Not looking good.

Edit: I almost forgot. One more tick on the pros. Getting replies from Mr. McGowan and others from PS Audio is worth a few ticks on pros.

We honestly never thought about adding a ground post. The thought simply never occurred to us. In the 40 years I have been making and designing amps we’ve never added one. Probably should have thought of it, given our love of REL subs.

The Amazon fiasco had nothing to do with dumping. What you have is a great deal on a great amp - and if you ever want the few tweaks we subsequently made we’re happy to do those for free for you and without any hassle.

Here’s what happened. Amazon wanted to get into high-end audio. They figured they could sell anything and placed a really big order for amps for us. Really big. We built them and shook our heads wondering how the hell they would be able to sell this amp. We weren’t wrong. They couldn’t. Then they started dumping them and we got pissed. We bought back as many as we could but they wouldn’t sell them all back to us. The ones that remained went out the door for prices getting close to what it costs us to make it.

You scored big.

t makes sense for Amazon to try to sell high end; they sell just about everything else and people are very accustomed to on-line purchases. I suspect the problem is that high-end is a little bespoke. Point and click does not quite fit how we shop for high end gear.

Mr. McGowan,

Thank you for sharing that information and for the offer to upgrade the amp. I assume the subsequent tweaks are worth it, otherwise you wouldn’t have made them. I would like to take you up on the offer but the question remains; will the tweaks eliminate the sub hum, loud hiss, and will it run cooler? Based on what I’ve read in the forum, it does not seem so. By the way, the excessive heat matters because I live in a 1957 ranch house with original single pane windows and thin walls and roof lacking insulation. Divorced teacher in San Diego. It’s all I could afford plus I chose music hobby over upgraded windows.

I’m still putting the amp through its paces, so no verdict yet.

Side note:I originally placed an online order for the BHK 250 on psaudio.com. I immediately got an email from Kevin notifying me that the Amazon payment had not gone through. I called back and finalized the order through the phone. I then went to Amazon to investigate what had gone wrong with the online payment. Out of curiosity, I searched for PS Audio BHK 250. I was shocked to see the amp selling for way less and with Prime Shipping! There were two black ones left so I bought it immediately, with one day shipping, then notified Kevin to cancel the initial order.

FWIW, my A2 series BHK 250 had a unstable D.C. Bias voltage problem. While it was being fixed, PS Audio upgraded it to an A8. Besides the original problem being fixed, I don’t notice anything different with the amp. YMMV.

I was just looking at Amazon, quite the price break on the BHK Monos.

I replied to some moron who recommended buying ATI, rather than the BHKs. He says with tubes there will be maintenance. What an idiot, I couldn’t resist replying. And of course not a confirmed buyer.

Did you all know ATI builds amps for some of the best names in audio? I know they used to build amps for CAT custom installations, until they went to a more upscale amp supplier. That was what they told me when I enquired about a used CAT amp on eBay. ATI, never even replied to my enquiry. Needless to say, I didn’t buy the amp. This was a few years ago.

Well, I put my BHK 250 through its paces this weekend. I’m not letting go of this bastard. Wow! I’m ashamed to have mentioned my McIntosh integrated in this forum.

The REL sub hum is simply a first world problem that I can easily solve by switching them off at night.

The hiss coming from the speakers is not audible once the music is playing. Doesn’t seem to affect my enjoyment of the sound quality.

The heat is still surprisingly high, but again, a first world problem. I assume it will be fine, as long as it doesn’t go into protection mode.

My only remaining concern is the amp’s early serial number (first-run specs). I would like to take Mr. McGowan’s offer to send it in to bring it up to spec. Who do I contact for this?

I should probably start a new topic with this question, but here it goes. What am I missing from not having a preamp between my DSj and the BHK 250? My only sources are Roon/Tidal through DSj (Bridge II), Sonos Connect (Digital Coax), TV (Toslink). No other sources planned. The DSj already has the inputs I need. Do I need the BHK Signature Preamp for some other reasons not related to inputs?

Preamps, especially one like the BHK bring a certain openness and magic to the sound you don’t get without it. I wish I fully understood why but I don’t. I just know that for all the years I poo poo’d this, I was wrong.

If you want us to upgrade the amp contact our customer service department by calling the number on the top of this page and they’ll get you an RMA number, check the serial number, etc.

We’re happy to take care of you.

Now I understand why PS Audio has a 30 day no hassle return policy. Who in their right mind would return any of it? I’m really enjoying my DSj and BHK 250. They sound amazing through B&W 805 D3 and a pair of REL T9i subs.

Next stop, P10…