Hsu ULS-15 vs. ULS-15 dual drive vs. Velodyne DD15 vs. SVS PB13 Ultra

[pjp993]

I was just wondering which setup would work the best. The sub is going to go in my family room and it's a pretty open area. It's about 20x20x12 (wxdxh). I want something that will fill the room with bass during movies and it will be off to one side by a wall (not a corner). While I'd like it to be behind my sofa, I can't get a wire (hidden) to it since it's in the middle of the room and that's why I was considering the dual drive. But with the dual drive, I am afraid of interference from my wifi and cordless phones. Which sub do you think would be best for movie watching? I would like it to go pretty low in terms of overall response.

[Pete_Hsu]

Hi pjp,

I would highly recommend the DualDrive system due to the very deep bass extension, high output, and compact size. Note that if one does suffer from any wireless interference, they can always use the wired connection as a backup.

Sincerely,

[pjp993]

Ok. I probably will end up with the dual drive, although I may end up getting one ULS15, testing it out and then getting a second one. It'll cost a little more that way, but it may be easier than buying a dual drive and then returning it if I realize it's too much.

[pjp993]

I have a couple of questions about purchasing the subwoofers. I know the website says if we're in Orange County, we can try out the woofers, but what if I want to buy them there, is that possible? And also, would there be sales tax instead of shipping? Thanks...

[Pete_Hsu]

Hi pjp,

Sure, you are more than welcome to come to our facility to pick up the unit in person. I recommend calling one day in advance to make sure that we have the unit built-up and in-stock. We still have to charge sales tax though.

You can always start with one ULS, and then if you add a second one within ~ 30 days, then we will still give you the DualDrive package price in total.

Thanks

Sincerely,

[pjp993]

Alright, I went ahead and ordered the ULS15. Hopefully it gets sent out soon, I can't wait to try it out. I'll post my impressions when I get a chance to check it out.

[Pete_Hsu]

Awesome pjp, thank you so much! The unit should ship out right away. We are very much looking forward to first impressions, and hopefully sometime down the road you will join in the fun that comes with adding a second subwoofer :)

Sincerely,

[pjp993]

Ok.. So I've added the ULS15 to my home theater set up in the family room. The front speakers are Revel F52s and the center is a C52. The ULS15 is about 10 feet to the left and 5 feet in front of the listening position against a wall and underneath a flat table. The subwoofer has a foot of clearance to the right and left of it. A couch is about three feet in front of it and it is about 5 inches from the wall behind it. I have the volume set at the 2nd line (as per the instructions) with the crossover set at 80HZ. I let my receiver automatically detect the speaker distance and necessary volume adjustment after that. The bass is much better than my previous woofers but I'm wondering about two things..

1) Does having the subwoofer behind a couch (but facing toward it) cause the subwoofer to work harder than necessary and possibly cause it to get distorted by the time the bass reaches the listening position?

2) How would I set the ULF setting for the room which is fairly large taking note of the fact that the woofer is under a long table? Should I set it to a higher level? I believe it is set to the 16hz that it was set at when I received it.

Thanks.

[hometheatergeek]

Hey pjp993

Welcome to the club man. You are going to really enjoy the new sub more and more each day.

1) You will not be working the sub any harder with it firing toward the couch. It will give you a nice tactile feel and that is all that matters.
2) On the ULF trim they only way to know which is better for your room is to play some of your favorite demo material and see what it sounds like. Mine are set at 16 hz because I bought my Dual Drive specifically for the lower octve notes since I already have two Velodynes for mid bass. But if you feel you are missing some mid bass info then raising the ULF trim might help. This is the part of the hobby that makes it fun don't ya think? :) :cool:

[pjp993]

I guess my question is really what does the ULF Trim do? Does it allow the sub to go to 16Hz? And then if I raise it to something higher it cuts off at that level? I'm seriously debating getting the Dual Drive, but I'm trying my best to hold off.

[Pete_Hsu]

The ULF trim allows one to adjust the [anechoic] low frequency rolloff anywhere between 16-50Hz. So if it is set to 16Hz, then the subwoofer response will be gently rolled off below 16Hz (as measured in an anechoic environment). If it is set to 50Hz, then the subwoofer response will be gently rolled off below 50Hz (as measured in an anechoic environment). At higher ULF trim settings, the rolloff frequency is higher, but the rolloff rate is also shallower too.

Having a subwoofer in the nearfield close to the couch is fine, provided that there are not large openings near the listening position. Feel free to experiment with the orientation of the woofer, as you may prefer one orientation vs another.

Sincerely,

[pjp993]

I haven't Had a alchance to move the subwoofer around yet. But just to clarify, the subwoofer is facing the L part of the couch that's to the side of the listening position. If I put the subwoofer behind the listening position it would be near the kitchen and shake the dishes too much.

How exactly does having two subwoofers increase the lower overall frequency response?

[Pete_Hsu]

Could you describe your room in a bit more detail, including info on where the listening position is relative to front/back/side walls, room dimensions (HxWxD), openings to other areas, etc? A rough sketch of the room layout would be great.

Adding a second identical subwoofer gives much higher headroom (up to 6db higher output capability at all frequencies), lower distortion, better long-term reliability, and potential to smooth out frequency response.

Sincerely,

[pjp993]

Ok, I'll try to describe the room in detail and if that doesn't work then I'll sketch it out. The room is roughly a 20' by 20' square. On the east end is the TV and entertainment center. The TV is 75 inches wide, then there are two 4 inch dividers/pillars, and then the Revel F52s. To the left of the left F52 (looking at it from the listening position) is a 4 foot hallway opening. To the right of the right F52 is a caddy cornered fireplace. The south wall has a couple of 8 foot windows (that do not open - so no rattling!) and a door. The west wall is only half of a wall with the second half opening into the kitchen. The north wall extends from the hallway opening in the east wall and after about 12 feet there is an opening for the wet bar. In that 12 foot space there is a marble table and underneath that there is the ULS15.

As for the listening position. It is approximately 11 feet straight back from the TV. However, the couch is L shaped with half of the couch running parallel to the north wall (in front of the subwoofer) and the other half (with the listening position) running parallel to the west wall in front of the kitchen.

There is about 8 feet between the west wall and the listening position. There is 6 feet between the north wall and the couch in front of it.

So if you visualize all of that, the woofer is about 4 feet in front of the listening position and 9-10 feet to the left.

I have to get a cable splitter to try out the wireless transmitter. I did not know that I had to use both the left and right input on the transmitter. But my worry about the west wall/kitchen wall is that the bass may shake the dishes, etc. a little too much. That leaves the small area between the fireplace and the south wall to put the subwoofer.

Opinions?

[hometheatergeek]

Hey PJP,

No one can tell you where to place the sub in your room. Only you can determine where it should go. One of the features of the sub is it's wireless capability. Therfore you will be able to place it where it will sound the best in YOUR room. This is know as the crawl test. Once you get the splitter and have the wireless working position the sub just in front of your couch. Play some music that has a good amount of bass in it and walk or crawl around the room paying close attention to where the bass sounds the best. You are listening for the smoothest, tightest, non boomy sounding bass. Not necessarily the loudest bass just the best sounding bass. Continue to walk around the room and make notes as you listen. Once you find a suitable place then you can place the sub there and it will sound it's best where you sit on your couch.

Using the crawl test, place the sub at the LP and see if the sub sounds the best where it is located now. But also move the sub along the south wall in various locations to see if it sounds better there. Try the corner near the fireplace, mid point along the wall, near the door on the south wall or the southwest corner of the half wall.

You will have to make some compromises of your placement since you are not in a dedicated HT room. So no matter what sub you buy you are looking for the best place in that room. You have bought one of the best available right now but these subs really do work better as a pair or Quad system or to get the best of both worlds a MBM from Hsu also might help out in your room to add the little extra mid bass most ppl crave. It does take awhile to appreciate accurate bass vs loud bass so enjoy the adventure.:)

Hope this was helpful. Also check out these articles (http://www.avsforum.com/avs-vb/showthread.php?t=824554)

[pjp993]

I went ahead and bought the splitter so that I could hook up the wireless transmitter and then moved the ULS to the corner by the fireplace and it sounds great. I watched a little bit of Sherlock Holmes and Avatar to test it out and the woofer sounds very smooth. But the size of the room still makes me want have have base coming from different sides of the room so I'm leaning more and more toward getting the dualdrive. I still want to move it around the room a little to see how it sounds against the south wall and west wall but it looks like I'll probably get another woofer. How is a Dualdrive system connected to a receiver with only one subwoofer LFE out? Am I going to need multiple splitters or do I just put all the woofers on the same channel with one transmitter?

[hometheatergeek]

Isn't bass addictive? You definitly will enjoy the Dual Drive and before you know it you will have 4 subs like me.

You can run 4 ULS-15's on one transmitter so you only need the one splitter.

Have fun :D

[pjp993]

What if I wanted to keep one subwoofer wired and the other wireless? How would I wire them then? I'm just curious since I had a wire put in the wall so that I could put a subwoofer against one wall and now I'm not using it since I went wireless.

[Pete_Hsu]

The placement near the fireplace is pretty good. Try to place the subwoofer(s) as far away from the largest opening as possible.

When using only the 'Wireless' connection, one can theoretically use any number of ULS subwoofers set to the same wireless channel.

When using one sub 'Wireless' and the other sub 'Wired', simply split the signal at the subwoofer pre-out on the receiver. Feed the left/right inputs on the wireless transmitter to get the Wireless signal for one sub, and feed the left (or right) input on the second sub to get the Wired signal.

It seems that you have a large overall volume of space to fill, with openings to other areas too, so I highly recommend adding a second ULS at some point.

Sincerely,

[pjp993]

I will most likely get another sub within a few weeks, some time after I get back from vacation. BTW, how would I order the second one in order to still get the dual drive price? Do I need to call?

So if I understand correctly, I would use one Y adapter to separate the subwoofer signal from my receiver into left and right. One of those (let's say the right one) would go to my wired sub, and then the other (left) would go to another Y adaptor which I would use for the wireless transmitter?

[Pete_Hsu]

Feel free to call us about a second ULS pjp.

That is correct regarding the wiring.

Sincerely,

[hometheatergeek]

I knew it wouldn't take long to get the sibling.

Sure hope you will post some pictures of your setup. I have installed the Revels in the past and know they are some of the best sounding speakers in their price range. You will have a very nice well rounded system when you are done. Can I come over and hear it? Can I? hmmm? :D

[pjp993]

I'm pretty close to getting the bass right where I want it, but I'm going to need to a put another subwoofer (at least) on the other side of the room. Then I'll take a picture after I get that set up.

Hey Pete, any deals if I get two more subwoofers instead of just one?

[Pete_Hsu]

Most likely an order of three ULS's would have a per unit price that is close to the DualDrive per unit price, although we may be able to work with you a little bit on that. QuadDrive is still the most cost-effective from a per-unit standpoint :)

Sincerely,

[pjp993]

I went ahead and order another ULS, but I seem to have a problem with the first one. It seems to get really distorted at the really low end and I'm afraid it's messed up. I'm not sure what the problem is, but the second one is supposed to be here tomorrow, so I can compare the two. Hopefully it's no big deal, but I just wanted to post it. I'll be out of town for a week so if there's something wrong, I won't be able to send it back for a week or two.

Also, when using the wireless connection, I get a click every few minutes or so (at random times) out of the subwoofer. I've switched through all the channels and channel 4 seems to work the best. The other channels kill my wireless internet router signal. Is the clicking noise a common thing for the wireless connection?

[hometheatergeek]

Hey pj,

You wouldn't happen to have Audyssey's Dynamic EQ turned on in you AVR?This sometimes can mess with the really low notes when you play the content at elevated levels. Dynamic EQ tries to boost the low end when you are listening at lower volumes and seems to not correct properly at more spirited levels. I do not have a Audyssey equipped AVR so I have not experienced that problem but have talked to other owners who have noticed the same thing.

[Bill Mitchell]

Let's assume the answer to hometheatergeek's question is yes, that you have an Audyssey enabled receiver. Audyssey equalization can provide a boost, up to +9 dB. Such a boost can strain the sub, particular when DynEQ is added on top of this. One approach is to tweak the ULF trim a little higher, reducing the low end, knowing that Audyssey will add in about 9 dB here. The end result should be that, with the ULF trim a little higher in frequency, Audyssey does not push the sub any harder than did the original ULF trim and Audyssey Off.

A tool like Room EQ Wizard (http://www.hometheatershack.com/forums/rew-forum/) can show you what is really happening down there. You can determine where the sub rolls off in your room, then tweak the ULF Trim so that you have the same rolloff when Audyssey is enabled. Or you can take the pure empirical approach of nudging the ULF trim up whenever you notice the problem, until the problem doesn't happen anymore.

Another possibility is that some have observed clipping in their receivers from too high a sub trim, and this can be aggravated by Audyssey's equalization adjustments. If your receiver sub trim is positive or just a little negative, you might try increasing the gain on the back of the sub, compensate by adjusting the trim downward on the receiver or re-running Audyssey setup, and see if the symptom goes away. (The engineer's approach would be to hook an oscilloscope up to the output of the receiver and see at what volume setting clipping appears.)

[Pete_Hsu]

pjp, may I ask what volume/crossover/trim settings you have on the ULS amplifier, and what crossover/level settings you have on the receiver? Try playing the Hsu test CD, tracks 9 through 16 (ie. 16-80Hz). Does the unit sound distorted on all frequencies, or just low frequencies? Does this distortion happen at low playback levels, or only high playback levels?

Thanks

[pjp993]

The crossover settings on both the receiver and woofer are at 80Hz. The volume setting on the woofer is at the 2nd notch while the recievers auto-calibration unit ups it to 5db. The ULF Trim is set at 16hz. The crossover is set to out and phase is at 0. Oh, and it's a Pioneer Elite receiver. I don't think it has the Audessy, but it has it's only auto calibration setup. Should I be keeping the receivers setting at 0db for the subwoofer?

It only gets distorted on the low frequencies and at fairly high volumes.

After saying all that, I'll try out the test CD but it seems like there was noticeable improvement after switching the wireless channel to 4. I'll hook up the second woofer (which arrived today btw) and I'll play with it more tonight and Saturday and let you know what I find.

[Pete_Hsu]

Sounds like the woofer is simply reaching it's excursion limits at high playback levels. On the subwoofer amplifier, set the volume knob to ~ 11 o'clock position (about 1/3 of the way up), and set the ULF trim setting to 50Hz. On the receiver, set the subwoofer channel level to +0dB. Then increase or decrease the subwoofer channel level in 1db increments to your tastes.

The second subwoofer will give you much higher headroom. You will be able to push the system much harder before running into any audible distortion. To maximize headroom, place the second subwoofer next to the first subwoofer.

Sincerely,

[pjp993]

Well I've tested out both subwoofers and there is definitely something odd (if not wrong) with the first one.

It doesn't rattle specifically at the low sounds. It rattles randomly. I tested this using the included CD and at 16hz everything sounds fine (most of the time) but randomly with the musical pieces (especially track 2 at 3:00 minutes) it will start making rattling sounds. I'm not sure if it's the woofer or if there's something else. It sounds almost like popcorn or marbles (i.e. something loose) inside.

And this is when I compared the two woofers side by side. The new one never did it, but the one I bought a few weeks ago did. And I'm pretty sure it's done it since I first received it, but it was less often. I'll get an RMA number, send it back and have Hsu check it out.

On a side note, putting the two subwoofers next to each other definitely increased the headroom and the lower level response. They sound great but I'm not sure if I want to keep them both by the fireplace.

First things first though. I'll have the first one checked out and then see how things go.

Hey Pete, if you read this post, I'll probably get the RMA tomorrow, but I can't send it back until a week from now.

[Pete_Hsu]

pjp, try playing tracks 9 through 16 (ie. 16-80Hz test tones) on your first ULS. Do you hear distortion from the unit with any of these test tones? Does this distortion happen at low and high playback levels? Does changing the ULF trim to 50Hz reduce the distortion in any way?

We can discuss over the phone tomorrow.

Thanks

[pjp993]

Just some follow-up.. I got back one of the ULS15s that I sent back to HSU for them to check out. They weren't able to find anything and in retrospect it must have something to do with the wireless signal. I had my home theater guy run another wire down the right side of the room so now both ULS15s are wired with one on each side of the room (to the left and right of the listening position).

They sound great but the subwoofer I sent back the HSU seems to get distorted a little earlier then the second one. By this I mean that I have both subwoofers set at the same volume level and trim settings but one will get distorted at a low frequency while the other did not. I switched sides of the rooms and the same one still acted a little quirky, so all I did was turn the volume know down a little and now it doesn't distort no matter what I throw at it. While it is odd that one subwoofer distorts a little easier than the other, overall they sound great. Has anyone noticed this with their dual drives?

I would consider getting a third woofer to put behind the listening position, but since it's the same price as getting just one woofer (3 ULS15s vs. Quaddrive pricing), I may hold off for awhile.

[Pete_Hsu]

Hi pjp,

Did you gain match each ULS-15 when comparing them, or did you just set the volume knob at a certain level by eye? Note that the volume knob marking can be a little bit off from one unit to another. So the only precise way to gain match is to use an SPL meter and a test tone CD. Start with one sub, place the SPL meter at a fixed position, play the 50Hz test tone (track 14) on the test CD, and note the SPL meter reading. Then take the second sub, put it in the exact same location as the first, play the 50Hz test tone, and adjust the volume knob until the SPL meter reads the same as that for the first sub.

Of course, you will want to make sure that the ULF trim and crossover switch settings are identical for each unit, and the two subs should be in phase with each other (ie. turning on the second sub leads to an increase in output, rather than a decrease in output compared to just one sub).

Sincerely,

[hometheatergeek]

I switched sides of the rooms and the same one still acted a little quirky, so all I did was turn the volume know down a little and now it doesn't distort no matter what I throw at it. While it is odd that one subwoofer distorts a little easier than the other, overall they sound great. Has anyone noticed this with their dual drives?

Looks like you solved the problem by adjusting the gain on the suspected sub. I have not noticed any distortions out of mine but then again I had gain matched my subs by Pete's recommended way.

Hope you are having fun now. :) If you want to give them a really hard workout, rent War of the Worlds on Bluray. :eek:

[pjp993]

So would a RadioShack SPL meter do the job or should I look for another one?

[hometheatergeek]

So would a RadioShack SPL meter do the job or should I look for another one?

Yes sir. The analog one is what I have been using for many years now. About $44 at Ratshack and you can also find used ones on ebay for around $30.

[pjp993]

Cool, thanks. That one subwoofer still acts up. I know the volume knob is just an approximation, but one subwoofer is halfway between the 2nd line and 3rd while the one the acts up is at just the 2nd line. That seems to be big difference even if its just subjective.

Oh, and hometheatergeek, if you're referring to the War of the Worlds movie with Tom Cruise, he's fallen out of favor with my wife so I'll have to find another movie to push the woofers. :)

I was thinking about switching to a receiver with a *.2 or *.3 subwoofer channel like the Denon AVR4810CI. Would that make a difference over having just one dedicated subwoofer channel. It seems like it would be the prologic version of subwoofer outputs since I don't seem to come across any audio or video tracks that support multiple subwoofer outs natively.

P

[hometheatergeek]

Cool, thanks. That one subwoofer still acts up. I know the volume knob is just an approximation, but one subwoofer is halfway between the 2nd line and 3rd while the one the acts up is at just the 2nd line. That seems to be big difference even if its just subjective.

Oh, and hometheatergeek, if you're referring to the War of the Worlds movie with Tom Cruise, he's fallen out of favor with my wife so I'll have to find another movie to push the woofers. :)

I was thinking about switching to a receiver with a *.2 or *.3 subwoofer channel like the Denon AVR4810CI. Would that make a difference over having just one dedicated subwoofer channel. It seems like it would be the prologic version of subwoofer outputs since I don't seem to come across any audio or video tracks that support multiple subwoofer outs natively.

P

Yes it is the War of the Worlds. I am also not the biggest fan of Tom Cruise, but I am a fan of over the top bass movies such as the new BD of WOTW.

Most AVRs that have a .2 or .3 sub output just saves you from having to use Y splitters out of one sub out. IOW they are just summed inside the AVR. On the other hand if the 4810 can calibrate the subs seperately, using Audyessy then this would be beneficial in your case. But I have all four of my subs on one sub out and no EQ and do not have an issue like you.

On the other hand how about you keep your present AVR and purchase the SVS AS-EQ1 (http://www.svsound.com/products-parts-subeq.cfm) for $750. This eq will do the subs seperately and is very easy to use. See the post here in our forum for JerryMeeker's (http://forum.hsuresearch.com/showthread.php?t=29220) journey using the AS-EQ1. You could then set the subs gains to the same settings and the EQ would then compensate for each sub. But I am a perfectionist and I would still use a SPL meter to level match the gains before running the EQ. But that's just me.

But before you do anything why don't you call me. I've helped other ULS-15 owners and would be happy to assist you also. Check your PMs

[Pete_Hsu]

pjp, you should try to gain match each subwoofer using a SPL meter and a test tone CD. There is no precise way to do so by eye.

[pjp993]

Ok, I'll get the RadioShack SPL meter this weekend and see how that makes things sound and get back to you guys. If I've got any questions, HTG, you'll be getting a call!

[pjp993]

Hey guys.

I went to RadioShack and bought the digital SPL meter. They were out of the analog one.

I followed the instructions for taking the readings that were provided with the subwoofer. I set the receiver at the volume where the meter read 80db at the 50hz test tone (and I did each subwoofer individually). The readings are below.

Right woofer - 32hz/71db, 40hz/68db, 50hz/80db, 63hz/74db, 100hz/72db, 125hz/66db, 160/65, 200/69

Left woofer - 32/68, 40/63, 50/80, 63/73, 100/73, 125/66, 160/66, 200/69.

The left one is the finicky one during movies whereas the right one has given me any trouble whatsoever.

So now that I have these numbers (if they are what I need), is there anything I need to do?

[hometheatergeek]

Where did the gains end up at on each of the subs?

Now place them back where you had them before, rerun Audyssey and play some material.

[Pete_Hsu]

pjp, you should try to gain match each subwoofer (ie. set the gain equally on each unit). To do this precisely, start with one sub with volume knob at ~ 10 o'clock, place the SPL meter at a fixed position, play the 50Hz test tone (track 14) on the test CD, and note the SPL meter reading. Then take the second sub, put it in the exact same location as the first, play the 50Hz test tone, and adjust the volume knob until the SPL meter reads the same as that for the first sub. After that, you can adjust the subwoofer channel level on the receiver to bring the combined subwoofer level in balance with the main speakers using the test tone CD.

[pjp993]

Ok, I'll try the gain matching as you described Pete, and see how that changes things up. I should get a chance to do it tomorrow.

[pjp993]

Ok Pete, so I tried it your way and gain matched to speakers. The finicky speaker is set just above the 2nd hash mark (10-11 oclock) and the other woofer is right at the other hash mark. I've tried them out a little and haven't had any problems. But before I matched them up I had the first one at a similar position and the second one at a higher level. I'm assuming neither of them should give me trouble now..?

[Pete_Hsu]

Hi pjp,

Thanks for the update, yes, you should be in good shape now.

Sincerely,