Adding a sub woofer?
A preamp output can be inconvenient as unless it's truly balanced (into a balanced sub input...sort of rare unless using pro gear) it can require a long run of single ended cable...not so good. Not sure if "many" subs allow for speaker level inputs like REL (I use 2 RELs), but if they do that's great. I use a single ended stereo amp with the REL's high level inputs and it works amazingly well. |
REL is the current fad in subs, at least until the next one comes along. The solution with subs is to use subs. As in, more than one. Use four and no matter what they are you are practically guaranteed of excellent awesome bass like you never heard before. This approach is called a Distributed Bass Array and relies on the facts that all subs (yes even REL!) create lumpy bass, moving the sub around doesn't change this it only moves the lumps around, you can't tell where subs are anyway because you can't localize such low bass. So the answer is to use lots of subs, so each one puts out less bass, but all together they add up to super smooth, even, and incredibly deep bass. Use four and it hardly matters what they are, you will be impressed. Do a search and read, everyone who actually does it will confirm. In terms of connections you want the subs to be additional. That is, continue to run L and R full range. Doesn't matter how the subs are connected. Speaker level is as good as line level. It imposes no additional load or harm on the amp. You can even use line-level only subs and run them off speaker level, just use a cheap Line Out Converter (LOC) you can buy at Parts-Express for $10. My system for years was just like yours. Tube amp, great sound, just never had great bass. The bass now is awesome, no-apologies, SOTA bass. https://systems.audiogon.com/systems/8367 |
I prefer using line level with any sub that I have owned. Some prefer speaker level. It all depends on the main speakers that you are using with the sub. REL has been around for 30 years so I would not call it a current fad! https://rel.net/our-story/ |
Speaker level or line level is all the same and has nothing to do with the speakers used. Here's a very good technical article that explains exactly what the difference is: two resistors. https://www.epanorama.net/circuits/speaker_to_line.html/ This actually works, by the way. Its what I used to add a pre-out to my tube amp, as per the mod shown in the last photo. https://systems.audiogon.com/systems/8367 |
Pick your so called expert carefully, there is a massive difference between line and speaker level as the latter passes the sonic signature aka transfer function to both the sub and main speakers which results in better more coherent sound. Those with a poor understanding of bass fundamentals AND harmonic content will not get it. Bass, coherent bass is alive well above 100 hz. for a phd in active bass with high pass mains research Vandersteen subs. |
Extended discussion on this, started by me: https://forum.audiogon.com/discussions/how-to-connect-monoblocks-to-a-single-rel-sub-with-one-rca-in... Here’s the short version: I connected the monoblocks to the speaker taps. Red to Right, Yellow to Left, Black to Left. No problems and it sounds better then sending the preamp RCA out to the RCA input on the sub. Here's REL's position: https://rel.net/we-take-the-high-road/ Here's PS Audio's: https://www.psaudio.com/askpaul/the-best-way-to-connect-a-subwoofer/ I find one sub to be excellent. People have told me to get a second sub, or four. I am being cautious at the moment because I’ve heard that the interaction between multiple subs can cause problems (which can no doubt be solved) but for the moment, I’m liking what I hear so I’m not pressing the issue. |
"I’ve heard that the interaction between multiple subs can cause problems" Hilde45, I try to stay informed on the pro’s and con’s of using multiple subs. Would you be willing to share what these problems are, that you have heard of? I’m not trying to challenge or persuade you, and if you’d rather not, no problem. Duke disclaimer: I’m commercially involved with a distributed multisub system. |
Hi Duke, Another very experienced member (building speakers over 40 years) on Agon mentioned that a second sub *could* cause interference or node conflicts. I was debating if I should buy another one and I was having trouble finding an identical REL model (528). His handle is @decooney To be clear, he wasn't saying I would but that I could and that if one was enough for my room and it wasn't giving me issues, I could relax on that front and focus attention elsewhere. |
@hilde45, Duke, Take this with a grain of salt. Varies by the listening room. While I prefer stereo subs, it’s all room dependent IMO. Phase and frequency cancelation at varying lower frequencies "can" occur with two, particularly in uneven odd shaped rooms -or- in situations where you are not able to place a bunch of room treatments or not enough phase adjustment in the sub x-over itself. I try not to advise on this as its mostly due to an environment-room issue. I still run stereo subs now, and often times leave one subwoofer powered off based on my seating position [in my case, in a particular room]. If I run the same setup in a different room, with even side walls, no issue, dual subs works great. Again, more of a room problem and no guarantee until you try it either way, YMMV. |
I have a very good tube untegrsted in Ayon and a very solid Yamaha 2100 both have active preamplifier sections , SVS, or crutchfield sells a resistor adaptor that connects directly to speaker outs on the amplifier , it is more accurate and better Bass control if you sub has speaker inputs, like rel has it’s a very good setup . I use this which it has a + and - per channel ,you use awg 16 wire I use Neotech and crimp bananas to one end to go into the speakers ,the other side plugs into the adaptor board and there you plug in rca sub cables into the board ,the other side into the sub input , it’s sounds like a lot of work ,but it’s not and only $30 I Velcro to the back of the audio stand. |
Adding a sub(s) is one of the most challenging things to get the sound response you want. Ideally, what millercarbon suggests is the most sensible approach to this challenge. The approach to adding multiple subs (sometimes referred to as "swarm") is ideal. However if you are not ready to get multiple subs you can look at the various wiring techniques mentioned here. Or, you can look into integrating a sub(s) by using an active crossover with bass management capability. Those crossovers can be from reasonable in price to very expensive. My solution was getting an Outlaw ICBM crossover. Original retail was $250. Don't believe it's still in production but can be found in the used market. A crossover of this type, with sub out connection, can be connected between the pre and power amps to perform bass management as well as adjusting crossover frequency to the mains. Not the supreme setup but can make integration of a sub much easier. That's the most important thing rather that how you wire up the sub. |
Optimum solution is to roll the very bottom out of the main amplifiers and feed a low level signal to the sub. This is effectively an increase in main amplifier power if you listen to material with real low end, i.e. deeper than most 40Hz limited material. Sub must either be very efficient or have lots of power for a realistic bottom octave. The sub must have continuous phase, multiple crossover slopes and polarity inversion along with the normal XO frequency and level controls. Martin Logan X and some JL Audio series have all of the above. Without these controls, the optimum position maybe in the middle of the room. REW and a microphone can ease the integration task, but the learning curve is steep. see http://www.ielogical.com/Audio/SubTerrBlues.php for perils and solutions for sub integration. Two subs are optimum for stereo. A swarm gives even level at the expense of coherent phase. Discount most advice on audio forums as FanBoy prattle. As composer once opined of my system "Every OTHER subwoofer I've ever heard just boomed!" |
I own a pair of REL S2 SHO subwoofers. What I like about them is their high level connection as well as their home theater connection for sound effects when watching movies. I am glad I listened to the dealer because two rather than one. Their high level connection allows the to ack more like woofers than subwoofers to extend the bass seamlessly. The key is to make sure you set the volume so they don't stand out. I set mine at 40% volume. Otherwise, they sound boomy and they disguise the towers. When you dial them in, they take some weight off the main speakers and allow the mid tones to play clearer. Be curious to hear what volume level they se their REL's. Be sure to not buy too small a size. Buying too small will cause you to overplay the subwoofer and it becomes boomy. I was going to go with a pair of REL T9's but decided to go with the S2 SHO's. Glad I spent the extra money. |
@ieales, absolutely. I think top model JL Audio subs may be the best available and their price reflects that. To my knowledge nobody makes a stand alone digital bass management system. The most sophisticated versions come with full room control units/preamplifiers. I must say however that the current units are easier to set up than the TacT units were. Almost any audiophile should be able to get decent results. The hardest part is setting up the microphone in the right place. The down side is the additional expense. Having toiled with subwoofers since 1978 I can say unequivocally that you can not get the full benefit of subwoofers without a complete 2 way crossover, be it analog or preferable digital. For those unfamiliar with this, the crossover goes between the preamplifier and the amplifiers. All connections are line level. Using speaker level connections drops the impedance to your amplifier decreasing it's damping. It is not acceptable. Your money would be best spent upgrading your system before getting subs. |
Hi Ryan, Depending on how large your room is, what types of music you like to listen to and how loud you like to listen to it, a single PSB 250 or even two maybe too small. What are the pros and cons of using the sub's preamp level inputs vs the speaker level inputs in this application? In this case the pre level Inputs would allow you to use the PSB 250's low level input and output connection scheme that limits the level of the low frequencies reaching the mains. This setup would give you the most control and should be far easier to integrate than the other hookup methods. does an inline sub like this do any processing, will it color the mids and highs in some way or is it just a clean pass-through in terms of sending the signal along to the speakers? I did not read the owners manual all the way through but at the price point of the PSB 250 I highly doubt that there is any processing happening so it should be a clean pass through to your mains with the exception of the limiting of the level of the low frequencies below your chosen crossover frequency. You may also need to plug the ports on the RP8000F's to get the best results. I noticed that the RP8000F's can be Bi-amped. You may get satisfactory results with this option also if you can control the input gains of your amplifiers. |
Hello, I just added a pair of REL T9s to my system. The T9s are active/ amp driven down firing with a passive front firing driver. The T9i or newest model is the opposite with the front firing driver is active/amp driven and the down firing is passive. I feel the front firing is a better design for music. I like to use a pair of subs for the front. If you choose to go with a speaker terminal connection or speakon please call the manufacturer for setup. Differential balanced or mono blocks require a special termination due to the type of ground connection when connected to the speaker terminals. ( Very important so you don’t damage your other equipment.) I also prefer a sealed enclosure for music instead of a ported enclosure. HSU has a unique enclosure that lets you block the ports to turn the ported enclosure to a sealed one. Ported or holes in the enclosure go down deeper in frequency but the bass has less control. Great for movies to shake the room. Home theater works better with the ported enclosure to shake the room and can cost less per lower Hz frequency. I am doing two subs L/R for the front and a ported enclosure for the surround sound connected to the LFE /RCA connection on the surround sound receiver. Also sealed enclosures are usually very fast to help match to the front speakers especially RELs. Since you usually have only one active driver per sub I believe it sounds better to have two to match or add to your left/ right front speakers. Also this is much more balanced since you are setting the sub on the side of the speaker you are trying to improve. By adding more subs you can meld the subs to the system easier since you can turn the volume/gain on all the subs down to prevent the boom. That is why I like a separate ported sub for movies usually on the side wall in front of the seating area. I will probably get two more T9i RELs for the front and move the T9s / down firing to the rear of the room later. Sorry for the length of this post. Subs have a lot of detail to explain. When you decide to get a sub look up sub crawl to help set it/ them up. |
After moving some years ago, my listening space became smaller and the Vandersteen 2CEs I had were no longer a good fit. Replaced them with Kef LS50s and enjoyed the change but missed the low-end of the Vandies. Finally bit the bullet and got a Rel T/5i sub to provide the missing bass. Using speaker-level connection and corner placement, as recommended by Rel, I dialed everything in using 1/3-octave warble test tones and SPL meter. Adding the sub noticeably increased the soundstage (width & depth) and made for a much more enjoyable listening experience. Highly recommended for anyone with small main speakers. |
I have 2 REL S5 SHO's on Pass Mono Amps. I am using the REL LongBow wireless system. It allows me to only worry about providing power to the subs not running wires across the room. I have one near a far corner from the speakers and one behind me near another corner. The Longbow connects to the Pass via the speaker outputs via an Analysis Plus cable made for the REL's. It gives extremely fast and articulate bass not boomy. The advantage of using the amp output is the subs see the same signal as your speakers. Using a good digital power cord improves the imaging. I replaced the smps with iFi power supplies. Adding a PS Audio Noise Harvester to the outlets also makes for better imaging. |
By what metric do you ascribe orientation preference? IMO in the last 20 years, REL has degenerated into BuzzWord Bingo marketing hype preying on the uniformed: " PerfectFilter performs two seemingly disparate qualities; extending the strong, even response of the extreme low end of bass frequencies while simultaneously opening up air and delicacy in the middle and high frequencies of one’s system. Additionally, we applied customized PureTheatre™ filters to allow S/510 to keep up with modern theatre effects without breaking a sweat." Anything that changes the mid and upper frequencies is a TONE CONTROL! 30Hz is 30Hz REGARDLESS of whether it’s generated by Godzilla stomping or a JAV Recording https://pipe-organ-recordings.com/ Additionally, the S/510 is missing the controls necessary for seamless integration. Pass. |
If I may add my inquiry here to this fresh thread, it is related to the integration of the sub and would likely be good info for the OP. I have a Hsu Research TN 1225 x 2 sub set up that I have used for 20 years. I had it set up with RCA out of my preamp with the mains running full range. I recently upgraded my mains to Wilson Sophias that have much better low extension compared to my previous speakers. What I loved about the Hsu TN model was the separate amplifier that sits on your rack with a volume knob. The bass varies greatly from album to album so I was easily able to adjust the volume up/down as needed when I put on a new record. I disconnected these subs with the Sophias and am finding myself missing that really nice low extension, especially at lower volumes. I would like to try something more modern, like the REL. I am not sure why, but the Hsu sub did not integrate with my Sophias as well as my previous speakers. I felt it was because they didn't extend low enough and were in competition with the Sophias. With my old speakers, the bass was immediate once the sub was on but barely noticeable with the Sophias. My concern is getting a sub with the controls which are not as easily accessed dialed in to work all the time. Do you find that once you get the crossover and volume set for your system on a traditional single box sub that it doesn’t require adjustments? |
Do you find that once you get the crossover and volume set for your system on a traditional single box sub that it doesn’t require adjustments?I might have a situation similar to yours. My speakers go to 20Hz but I have a standing wave in the room that cancels bass at the listening chair even though elsewhere in my house the bass threatens the plaster. To break up the standing wave I added a pair of Swarm subwoofers, asymmetrically placed in the room. Once I got everything working I did not have to make any further adjustments regardless of the album playing. With a single sub this would be harder to do since you have less ability to break up standing waves. So how much bass you get will vary from album to album. |
Regardless of Millercarbon's snarky condescension (per usual), RELs are NOT inherently "lumpy" unless set up badly, and a single one can work. Not everybody has room for a Swarm of four subs and many can get along with one well placed REL or another well designed brand. And there is a big difference between high level power amp driven signal and a single ended preamp signal as ideally the sub should sound like the amp, and the high level REL style works swimmingly. For reasons noted by atmasphere and others, using two subs (I use 2 RELs) can eliminate standing wave issues and get a room in tune easily, but if you can't afford 2 subs, simply get one and add another later if you feel the need. |
One subwoofer can be very frustrating to an astute listener. Best to get at least two to start. Then they are matching. If you can't afford two save longer. If you use an appropriate crossover they will not color the midrange at all but interestingly give you more sense of depth in the midrange. There is more air in the room. It is an effect that most people notice. Turn off the subs and everything goes flat. But, the crossover is critical and the only ones that offer total control of frequency and slope are digital. People who are married to total analog miss out on this. JL Audio makes a decent analog crossover. |
I'm an "astute listener" and years ago added a REL Q150e which transformed my system...the adjustments on that REL are comprehensive for phase, level matching, and "crossover" matching, all easily done for excellent sound. Digital woofer control can add delay that isn't so great so I avoid digital nannies. |
I don't know that I have ever appreciated a change in the midrange of my system with the subs active. It is very intriguing how this could even happen with nothing changing at the signal the main speakers are receiving. I suppose it is all about room acoustics and not what is leaving the speakers' cones, but what ends up getting to your ears. |
I don't know that I have ever appreciated a change in the midrange of my system with the subs active.When done properly, i.e. not using idiotic full range pass through the sub but a crossover that removes the bass & possibly some of the mid-bass from the mains, the LF driver has a fair portion of its work removed, allowing it to better handle the upper part of its range. The mains' power amplifier loafs, having gotten an effective 2x+ power increase by removal of the lower registers. I'll wager dollars to doughnuts that six nines have never heard a properly integrated sub. |
I don't know that I have ever appreciated a change in the midrange of my system with the subs active. It is very intriguing how this could even happen with nothing changing at the signal the main speakers are receiving. The best answer to this is that removing bass from a mid-woofer reduces doppler distortion, which makes it's way up into the midrange.
Most people really have not. |
