SVS subwoofer

[mobile homeless]

I watched the "Fellowship of the Ring" last night in two channel.

A homebrew 2A3 single-ended triode amp to Cornwalls, with two 16/46's on each side.

This belongs in the "headroom" thread. We would definitely have the Audience Award at Sundance.

kh

[mike stehr]

I watched the "Fellowship of the Ring" last night in two channel.

A homebrew 2A3 single-ended triode amp to Cornwalls, with two 16/46's on each side.

This belongs in the "headroom" thread. We would definitely have the Audience Award at Sundance.

kh

Gimme a break........

[mobile homeless]

Gimme a break........

C'mon, stehr, where's the old Mike? Besides, we both know you need to put that thing back to 300B watts for the Cracks of Doom!

[Deang]

Pat, you'd be surprised at what a pair of RF-7's can do with a low powered tube amp. I ran mine with 15 watts for over a year and the sound was very intoxicating. I agree with some here that power requirements are often overstated. 3.5 and 8 watt amps didn't do it for me -- but a lowly 15 watts worked well.

[steamer]

"What model did you get? "

Should be a PB12. Marie wasn't so sure she wanted a 46" long tube sticking up in her room. "

That was in fact the case, and yes, this is the PB12 model. There are surely more expensive subs 'out there,' and this one seems very good to me.

Dee: Thanks for the confirmation on the SVS/Klipschorn combination. Wolfram also spoke highly about the SVS products (thanks, Wolfram!), and suggested it as something to consider if I gave in on a DIY project. I've loved building speakers in the past, but the timing might not be the best for something like that. And you're right, Marie is awesome!

Shawn reminded me about the importance of dialing the best phase response in relations to the main speakers, and I used to have a Stereophile test CD around here. I can't find it, and am relying on another, more intuitive (but temporary) way of doing this.

I have struggled with the integration of music and TV/movie for years, and had been very strict with myself in keeping the to separate from one another. It just makes more sense to integrate the two, and I feel the compromise with the center channel (which is also most likely temporary) was well worth the combination of one with the other. Certainly I would understand some skepticism about this one fact: We used one SE OTL (about 1.5 watts for those who aren't familiar with the amp) for the L/R amp last night watching Polar Express , and I was impressed with what it was able to do in terms of SPLs on some of the louder sections. Some of those shook the room (tip of the hat to the SVS), and the little OTL amp did very well. I'm working on a slight buzz with another one, but will have it in the system for two bridged -- a whopping 4 watts/channel for the Klipschorns. I can't wait![]

Erik

Erik,

I powered my La Scalas with Decware SE84CS monos(4 watts per) for about a week before integrating my Altec 511B/902 horns into a 2way setup.I was very impressed with only 4 watts of SET power.Yes I could make the amps run out of steam but it took alot more volume than I expected to get there!

As for your SVS subs...sounds like you have found a good match for the Korns that you like.Getting them to blend with the system and not sound disconnected is a long procces but well worth the time involved!

Hope you enjoy the new addition to your system.

Greg

[charlieboy]

Greg,

Hey bud did you remember you have dual 18" subs! LOL!

Charlie

[dubai2000]

In a sense this thread leaves me smiling quite a bit. Of course LOTR is

fun .... 'even' when using a SET amp that is supported by a good

quality sub - some people have been saying this for years [].

No, reference levels one might not achieve, but then some people DO have neighbours [].

Erik,

one more suggestion though: I have found that using an external active

crossover leads to better (read: cleaner) results than relying on

the sub's inbuilt crossover. Plus do play around with the subsonic

filter setting (and port blockers). In my room blocking two ports and

setting the subsonic filter to 16Hz works best...though that might

differ from room to room.

Wolfram

[sfogg]

Wolfram,

"one more suggestion though: I have found that using an external active

crossover leads to better (read: cleaner) results than relying on

the sub's inbuilt crossover"

Erik has no need. His pre-amp is handling all the crossover duties in

the digital domain (fed digitially from his source) as well as time

aligning the sub with his mains. It also performs peak limiting to keep

the sub from ever getting nasty sounding.

Shawn

[Erik Mandaville]

"The Klipsch gestapo thinks SVS makes good subs for the money. They are unconvinced of any blanket superiority."

Really? I have tried bunches of different blankets in my day! I've had wool ones (itchy!); down comforters (good in winter, overbearing in summer); thin cotton; flannel throws. I agree with them, though. It's all a matter of preference. I have friends who like down feather blankets even in summer! If only they would be willing to try much cooler and lighter 'feel' of cottom. Without a doubt, they would find that their ACs would have to work much less hard. AC's trying to cool sleepers poaching in down blankets (even if it's what they prefer!), are known to overload quickly, not to mention yank $$$$s out of bank like so many eager children with pockets full of pennies at the drugstore gum ball machine.

Erik

[Erik Mandaville]

Greg:

"Erik,

I powered my La Scalas with Decware SE84CS monos(4 watts per) for about a week before integrating my Altec 511B/902 horns into a 2way setup.I was very impressed with only 4 watts of SET power.Yes I could make the amps run out of steam but it took alot more volume than I expected to get there!

As for your SVS subs...sounds like you have found a good match for the Korns that you like.Getting them to blend with the system and not sound disconnected is a long procces but well worth the time involved!

Hope you enjoy the new addition to your system."

I bet that system sounded very good, Greg. One thing I noticed just with music this evening, was that our center channel, which is much less efficient than the Klipschorns, began to distort a bit with the bridged Moth 2A3 amp being used with it. I should note that this was at VERY loud levels, while the single-ended OTL amps (after a bunch of repair work I did on one, and a tube or two very kindly donated for the cause by sfogg) bridged for four watts on the Klipschorns weren't bothered at all.

We've got one SVS at this time, and it has added tons to everything. Fun is a big part of that! I still need to adjust and dial in the phase response. I don't have a test CD for this, but know of one way I could get a half way decent approximation of the best setting. I tried another approach for doing this, which is too dumb to even mention![]

Erik

[formica]

We also listend to music by Tony Levin

and Bill Bruford's 'Earthworks,' and the SVS filled in beautifully

well. I've been worried about possible over-loading of the room,

which can surely happen if the subwoofer is turned up too high, but at

the right level it provides I foundation for music I haven't heard

before (well, at least in our own system).

A properly dialled sub can really "strengthen" music playback...

I'm still surprised on how many people shy away from experimenting with

it in 2chnl. Perhaps I'm biased (given my musical preferences)

but... I'd be loosing over an octave of info on my khorns.

Sure wish I could come over and hear a

good sub implementation in a music only system. To this day, I

havent heard it. ... But I have yet to hear a sub

done in a way I like in dedicated music system.

Alot people tend to dial it in a little hot... but no reason why it

can't be done right. One problem that does occur though, when

adding a sub to your familiar albums, is that it may bring out recording

defects you hadn't noticed before.

Sorta like when upgrading to Klipcshorns emphasizing shortcomings in your audio chain.

And one of the problems I was addressing

in the layout as well was -- where the heck to put a sub. Short

of a teensy Sunfire sub (13" cubed), all the decently musical subs are

large. With Klipschorns and a Belle across the front, I'd like

something that is musical

Khorns usually use up the "typical" front corner placement for a

sub... but I'm sure there are several workable spots in your

room. You should post some sketches of what you've got to work

with in the architectural forum...

BTW, Danley definitely takes unconventional approaches in building his

subs, but he has produced some very interesting products in the

past. (i believe sfogg actually has a couple of his contrabass

units)

ROb

[sfogg]

"BTW, Danley definitely takes unconventional approaches in building his

subs, but he has produced some very interesting products in the

past. (i believe sfogg actually has a couple of his contrabass

units)"

Danley is IMO the most innovative speaker designer out there. He

definitly comes up with unconventional ideas to different problems.

I'd love to have a couple of the CBs... but have to 'settle' for just the one.

Shawn

[dubai2000]

Shawn,

stupid me, I should have guessed that his preamp has got a facility for

connecting and controlling a sub as well. Anyway, just in case this

thread is read by others as well, I thought I bring it up....again [].

Wolfram

[Erik Mandaville]

Wolram:

I do appreciate this extra information. The Lexicon does offer some very useful features. The added benefit is also that the Lexicon 'sounds' as good as it does. It can 'sound' all sorts of ways, too! It has a bypass feature for listening in strict two channel stereo, as well, which truly sounds better with some recordings we have than they do in surround. I don't have many that sound that way, but some. Used as just a linestage stereo preamp, the match with low powered triode amps is great for us.

I think the phase response with the mains is critical to making the best use of this new component, and I'm angry with myself for selling (or more likely probably misplacing!) the Stereophile test CD I used to have. It had test tones one it that would work very well for adjusting phase. I think I'm going to order one today.

What model do you have, Wolfram? I know you have told me in the past -- but I don't remember!

Erik

[Erik Mandaville]

Speedball"

"Am I understanding you correctly? Are you using a low watt SE tube amp for home theatre?"

Right now, yes. The only amp I use that isn't a low power single-ended amp is a modified Baldwin stereo 6L6 push-pull. Other than that, all of my amplifiers in the HT/music setup are SE triode amplifiers. A friend of mine here in Houston is loaning me his Transcendent Sound pair of SE OTLs, and he is in turning borrowing one pair of 2A3 amps I made (JFL Horus 2A3 parafeed). I had been using the Horus amps as the side channels (although they sound incredible too as the main stereo pair), and my Moth 2A3 amp bridged for mono on the center channel (an amp which also sounds really great as the L/R amp).

You have hit on an important point, though: Just yesterday, after I finally got both SE OTLs up and running in the surround system, I was playing music at what for me is extremely loud levels. At 4watts/channel in bridged mode, the Transcendent amps held up impressively well. Unfortunately, that wasn't the case with the center channel Moth. It displayed obvious signs of clipping out of the C-1 center channel, which isn't surprising given the real disperity in terms of efficiency in comparison to the Klipschorns.

This is a warning sign for me, because it's the clipping distortion of low power amps that often blows tweeter voice coils. I am going to try the Baldwin amp today which, bridged, will give me about 30 watts for the center as opposed to maybe 6 or 7. In this case, a SE triode amp is really not the best choice IMO (ahem....for those who enjoy the merits of low-power amps. ). Up to a point, the Moth works well, but when pushed too hard, it runs out of steam.....but does so pretty gracefully compared to some SS amps I've heard when driven into clipping.

The Baldwin is both about twice the size and 5 times the weight of the center channel, so it's kind of a strange combination in that sense! maybe the two will be happy together. I won't know until I try it.

Erik

[Daddy Dee]

Erik,

I'll be looking forward to hearing your take on the Baldwin doing center channel duty.

Bridged, what do you think the WPC of the Moth is?

[Chris Robinson]

"BTW, Danley definitely takes unconventional approaches in building his subs, but he has produced some very interesting products in the past. (i believe sfogg actually has a couple of his contrabass units)"

Danley is IMO the most innovative speaker designer out there. He definitly comes up with unconventional ideas to different problems.

I'd love to have a couple of the CBs... but have to 'settle' for just the one.

Shawn

Shawn,

I'm interested in the Tower of Power for two reasons: (1) it's horn loaded and (2) it can be stashed behind millwork (but ported at the bottom near the floor). In a 30 x 19 x 9 room, is this sub overkill? I'd really like it to blend in on music and do what's needed on movies.

The location of the sub would be just to the left of the center Belle. Is this center location ok for placement (i.e., firing right at the seating area and not in a corner)??

Thanks for your input!

Chris

[sfogg]

Chris,

I haven't heard the Tower of Power (would *love* to though) so I'm going on what I have read about it from those whoes opinions I trust.

"In a 30 x 19 x 9 room, is this sub overkill?"

Put it this way...... I have a ContraBass and four JBL Sub1500s (what was in the Revel Sub15) in a 17x9x7.5 room.

So... no... I don't think its overkill.

Having enourmous headroom in the system just means most times the system will be loafing along barely working at all. And when the times come for some serious dynamics (movies) you won't be limited in the bass region at all.

" I'd really like it to blend in on music and do what's needed on movies."

It will certainly do whats needed on movies.... and then some. It is one of the few subs that should have no problem with full reference level playback. Above 20hz I think it is roughly equiavlent to four ContraBass subwoofers! And it does that with a single 12" driver...... where each CB has a pair of 15" active drivers run by a servo motor through Kevlarish belts and a pair of 18" passives.

How are you planning on crossing over between the subs and the rest of the system on music/movies?

One thing to consider is the time alignment between the sub and the mains. Because of the delay through the horn sub itself just physically locating it near the mains isn't enough as the path length when the horn is included is longer. This actually is a little less of an issue with K'Horns since they have a longer path length in their bass horn but still is something worth looking at. The mains need to be delayed to get arrival times in sync between the sub and the mains.

"The location of the sub would be just to the left of the center Belle. Is this center location ok for placement (i.e., firing right at the seating area and not in a corner)??"

It isn't in the center though correct... toward one side of center? That should be OK. The direct center of the room is a bad location as it makes some of the room modes stronger since both side walls are the same distance away. But if it is off center that helps. One location that can work well for subs is about 1/3 of the way along the front wall.

I think Danley actually has a DSP option for the Tower of Power too. You give them room dimensions and placement and they can model a response curve that they will load into the unit to reduce some of the effects your room will have on the response. IME some form of EQ on the sub like that is well worth considering. It would be a shame to have a first class sub and then let a room totally screw up its response. Not that EQ can fix everything but it can help to get some things under control in the bass and make a large difference in sound quality.

Shawn

[dubai2000]

Erik,

PB12-ISD/2 - that model was actually suggested by Tom@SVS according to

the size of my room and to this day I am very (!) pleased with it [].

Wolfram

[Erik Mandaville]

This took me a crazy amount of time to figure out how to do, but here goes: The following should be a correctly sized and re-touched image of our front stage: Panasonic TV; front right and left channel SE OTLs, Moth center channel amp (temporary right now), and the Moondogs on the sides. Under the TV are the Lexicon and Denon 2900.

Erik