Spectrum Analyzer Results & Jeff's Take on the US Tax System!

[Deang]

Good post Meagain, you're hearing exactly what I expected you to be hearing.

The new networks will sound crisper at the top and not quite so harsh through the middle -- until you push the volume up a bit -- and this has absolutely nothing to do with lack of headroom. The harshness is caused by pressure build up in the small throat of the K-400 midrange horn which is exacerbated by a mouth that reflects energy back down into the throat. Because PWK valued high efficiency over all other parameters, the early Klipsch networks allow the midrange driver/horn combination to run unabated. IOW's, there is nothing in the network to roll or cut the horn's output -- the horn just goes until in can't anymore. With a very good horn the concept works well, but the K-400 is not a "very good" horn -- it's a horn that needs a little help, and once it gets it -- it can sound very good. You'll hear an improvement with the new parts in Rick's networks, but if you're a critical listener, you'll quickly realize the limitations of the improvement. Most eventually throw in the towel and opt for a network that's conducive to critical listening.

[Tom Mobley]

meagain,

this analysis or observation you've posted "Good things: Bass. Deep & punchy. I've no complaints.

Problems:

Some highs can be harsh (cymbal crashes). Sometimes sibilance(sp)

issues but I think that's mostly the particular recordings. " is pretty

normal for what happens when people hook up Khorns to a typical HT

receiver. Khorns are revealing and will display the

transistorized harshness lesser speakers gloss over.

The anomalies in the left channel as shown in the graph need to be

looked at. Best (but not necessarily most convenient) way to

address that is to reverse the speakers and re-run the test exactly as

run before. See if the anomaly follows the speaker or not.

if it does there might be an issue with the speaker itself. if it

stays on the left put the speakers back where they were and switch the

speaker wires at the amp, run the test again. if the anomaly

switches sides there might be an amp problem. if it doesn't

switch sides put the speaker wires back where they were and switch the

the L & R inputs from the CD player or whatever you're using, see

where the anomaly goes. if none of this laborious testing changes

anything there's likely an issue with nodes in the room.

Obviously it's important to maintain the testing as closely as possible

and also to put the stuff back like it was each time, otherwise you're

testing the combined effect of changing several variables, which is

meaningless. if you run through this basic testing people here

will be able to help you get it sorted out. Otherwise, you can

get an equalizer and start covering up anomalies by introducing others,

which is a long and depressing path to nowhere.

Just my $.02, YMMV, all that.

[Deang]

I don't mind off-topic material when it's stuffed in a half worthless thread -- but this one has some value so I thought it best to stay on topic. Sorry if I seemed snippy -- it's been a long week.

[ZAKO]

Meagain ....Your using a tool without calibration. The mic you have is not intended for this kind of testing. Your room is an unknown quantety. And mixed in with the measurment. ( A anechoic chamber would suffice) But it would help if you had a chamber. I have one at my testing lab. It would be nice if you had a chart recorder rather than try to dechifer a rack of numbers. Your trying to use a shovel to dig into a mountain. ( wrong tool). Sweep frequency Osc. plus calibrated mic plus chart recorder. It would be done in one min. Oh yes about $ 10,000 for a good set of instruments minus the chamber. Would you let me operate on your brain with a ice pick?

[Deang]

LOL

Well, of course Maron is right, which follows along with Ben's comments who was also correct. However, how about a little pat on the back for the attempt to at least measure something with something! Max has a very good point and I agree with him -- we don't need accurate numbers here, we only need numbers that we can compare to other numbers to see if we can pick out relative differences. Now, I don't know what happened to Bob, but I think he would agree with me that those numbers are exactly what he sees when the caps are ready for the trash bin.

[meagain]

LOL

Well, of course Maron is right, which follows along with Ben's comments who was also correct. However, how about a little pat on the back for the attempt to at least measure something with something! Max has a very good point and I agree with him -- we don't need accurate numbers here, we only need numbers that we can compare to other numbers to see if we can pick out relative differences. Now, I don't know what happened to Bob, but I think he would agree with me that those numbers are exactly what he sees when the caps are ready for trash bin.

Correct! I realize the test isn't pristine. It's for comparing. If the tools are faulty, then it will be faulty for each speaker and when manually switching the speakers. It's a baseline and I thought it would be ok to use it to compare apples to apples - despite maybe being rotten with worms. The Mic is still in the exact place & won't be touched for the next test (physically switching the speaks). Same volume, etc.

[Jeff Matthews]

I don't mind off-topic material when it's stuffed in a half worthless thread -- but this one has some value so I thought it best to stay on topic. Sorry if I seemed snippy -- it's been a long week.

No problem at all Dean. It wasn't taken as snippy, either. It is off-topic, and if we care to continue, we should move it. I moved it because it looked like Whell wanted to put his 2 cents in on the topic. It's in the General Forum, now, but you know, folks, nobody's gonna find the universal "truth." Let's keep things in perspective.

[meagain]

I'd bet money that Jeff runs a blog. Jeff - Am I right?

Since the thread is now all over the place (from the getgo)... I might as well toss in a newbie type question.... It's been suggested many times a pre-amp would be a good thing. Apparently my receiver ports allow for this.

1) If the pre-amp is hooked to my HK receiver, and assuming my HK is cr*p... wouldn't any good stuff from a tube pre-amp be negated by the HK?

2) If I have a tube pre, can I still use the HK remote for volume? Yes - right?

[3dzapper]

I think this may have been lost in the "rax debate":

Meaghan, Remember, you are measuring your room as much as the speakers. that said, you can see the room gain in the 150HZ octave that most rooms will exihibit. The relative inbalance between the speakers is more than likely caused by room reflection differences between the speakers. Things like hard walls, mirrors, oil paintings all reflect sound waves differently.

There are also a few things appearent that are intrinsic to the K-400 in the upper "presence" frequencies (1-2K octave). This is one area that AL K designed networks really shine, they allow one to take that extra Db or two, depending on room, out of the response curve as well as flatten out the impedence load further smoothing the response.

There is no definitive relationship between a good speakers frequency response plot and how it sounds. If one was to look atjust the frequency response plot of a $40,000 Wilson MAXX 2 speaker system it would be dismissed as a joke. However it is one of the best sounding speakers around. Why? Low distortion. Low distortion was PWK's holy grail.

http://stereophile.com/floorloudspeakers/805wilson/index4.html

Once you have your Khorns sounding their best, then it is time to tackle some of the room issues. This would hold true for any loudspeaker system, it's only as good as the listening room. You won't need ugly foam stuck to the wall there are other more subtle means to accomplish those goals. Things such as drapes, wall hangings and the material of the furniture all make a difference.

Rick

Like Dean mentioned, my experience has been that worn out caps exhibit themselves in excess siblance, harshness in the upper ranges. These losses also translate into mid-base muddiness. If you have been reading the threads that proclaim the second coming when others install new networks from Al or Dean, they all seem to mention the new "clarity" in the bass even though the bass section is basically the same as the original design, a single 2.5mH inductor sending frequencies over 400Hz up the chain.

Rick

[intotubes]

"If I have a tube pre, can I still use the HK remote for volume? Yes - right? "

Prob'ly not. But there are pre's with remotes.

[MarkBK]

Hi Dean

1981 Khorns with AA's

Harman Kardon AVR 435 (65 wpc w/peak of 85. Various dig/analog ports to chose from & able to do pure 2 channel if desired).

Room size: (bad) Khorns are on 11.5-12' wall & we're sitting a bit back from what "I" think is the sweet spot. ... ... ....

I'll be happy-ish if someone tells me the numbers above do not show defects in a given horn, etc. and are just a result of my room. I can then cross that off my list.

So Dean, do the numbers above look appalling to you or are they just in the normally semi-bad category and merely an effect of the room?

Meagain,

It would be more helpful to know more detail of Room size and where you are sitting - supplying info on the one wall width isn't much help.

Like I and many others have said earlier in the post - you are measuring some of the room.

Dean and BEC are quite knowledgeable in regards to crossovers - trust them - there are many who have over the years.

Bear in mind - you have set up a VERY temporary false corner - and that is in front of a fireplace hearth - is also playing a VERY significant role.

[ricktate]

Are you going to run the test with the rebuilt crossovers? The shrillness could be the caps or the amp when i got my HK430 i noticed a much better sound but i had already installed the ALKs home built.Not to get back on amp power but my old HK with 25 watts outshines my high cost 80watt Yamaha any day of the week go figure...lol.Im not saying i dont like my Yammy but i like the HK better.As far as remote controls go is there a reason you need remote? I got my electronics in another room in a closet and have to get up to change stuff.Glad to see this post back on track helping Meagain...remember this is fun.....enjoy it... dont argue.What Meagain has done so far is good i think.Rick

[Deang]

If the K-horn is not sealed against the panel, and/or the panel doesn't come at least even with the front of the K-horn -- then there will be suckout at around 250Hz, and diminished response the lower you go. Looking at the numbers I don't see a big difference between the left and right speakers in that area.

At only 12 feet apart -- your "sweet spot" is about 5 feet in front of the speakers. Not what you wanted to hear I bet. Sorry!

The variences in the numbers between left and right for the most part look relatively normal to me. Most of that is definitely the room, and the great majority here who forgo equalization probably don't fair much better. However, as you move into the high frequencies you can clearly see what's happening:

340 14664.11 20.0

340 14664.11 18.8

357 15396.24 15.0

357 15396.24 16.3

358 15439.31 13.8

358 15439.31 12.8

361 15568.51 11.0

361 15568.51 11.5

371 15999.17 11.0

371 15999.17 11.0

375 16171.44 14.0

375 16171.44 10.5

380 16386.77 10.3

380 16386.77 9.3

381 16429.83 11.0

381 16429.83 7.3

387 16688.23 7.3

387 16688.23 4.8

391 16860.50 5.8

391 16860.50 2.3
Expect to see all the numbers go up, and to see the ones toward the end to move up even higher still and move closer to the other others.

[meagain]

Thanks. Yes, the right speaker has a 1" thick MDF wall (which we since lengthened another 2'). I had a bit of a problem accepting the need for a serious level wall with studs, insulation, etc. Quite frankly, this bad room we're in doesn't have walls that nice.

The MDF is wedged in solid and can't be moved by hand. Braced from behind by the fireplace ledges. The foam on the tail board is snug against it. IDK - Maybe some pading between the ledges & MDF is in order. I've seen pics here of others creating falls walls that lack true studs/insulation so I went with that. The MDF is not screwed into the khorn. Didn't want to ruin them. Anyway, it's the right speaker. Don't know if the specs reflect this issue or not.

We'll physically switch the 2 speaks as soon as hubby gets home then retest.

I can't wait to put these x-overs in. I sure hope I get better results than Jeff. At least something perceivable. At least we have 2 listeners here.

[Deang]

I'm sure to take a beating for saying this -- but you're HK is fine for now. Start with the speaker and work backwards.

[MarkBK]

I'm sure to take a beating for saying this -- but you're HK is fine for now. Start with the speaker and work backwards.

I agree with Dean - worry about the speaker tweaks first, then room.

[meagain]

Ricktate - The lack of being able to use a remote or program my pronto for volume control might be a deal breaker for me. EDIT: Yes, I'm going to redo the test w/the new xovers. Should I post the numbers?

Dean, the khorns are sealed in the corners with pipe insulation. They are shoved in tight. The 1" MDF wall extends at least 3.5' maybe 4' beyond the edge of the khorn.

Yea, I know we are sitting too far back. About 9-10' from the wall?

Think there will be a vast difference to our ears if we temporarily move the sofa where we sit? Vast?

See - this is why we were going to buy that Behringer deq 2496. To be able to compensate a bit for the room. Despite it being a bandaid. I'll sit in the sweet spot for a good listen today.

[meagain]

I'm sure to take a beating for saying this -- but you're HK is fine for now. Start with the speaker and work backwards.

That's what I'm thinking. Otherwise... $$$$$$$ and still might be unhappy.

Dean - I saw a thread you started on the Behringer deq back in June/July or so? Given you have experience with this and given my room is defective... do you think it might offer me improvements? At least compensate for my room? I'm just seeing this as a fairly inexpensive practical purchase that can be used in various future settings, etc.

After I listen to the recapped crossovers of course. But to me, no matter what I do, I'll have room issues. Even if I have a $10k amp. Right? It'll help make things more pristine even in a pretty good room, etc?

[MarkBK]

Thanks. Yes, the right speaker has a 1" thick MDF wall (which we since lengthened another 2'). I had a bit of a problem accepting the need for a serious level wall with studs, insulation, etc. Quite frankly, this bad room we're in doesn't have walls that nice.

The MDF is wedged in solid and can't be moved by hand. Braced from behind by the fireplace ledges. The foam on the tail board is snug against it. IDK - Maybe some pading between the ledges & MDF is in order. I've seen pics here of others creating falls walls that lack true studs/insulation so I went with that. The MDF is not screwed into the khorn. Didn't want to ruin them. Anyway, it's the right speaker. Don't know if the specs reflect this issue or not.

We'll physically switch the 2 speaks as soon as hubby gets home then retest.

I can't wait to put these x-overs in. I sure hope I get better results than Jeff. At least something perceivable. At least we have 2 listeners here.

The MDF will work until you get other issues resolved. Most important issue is that the MDF is big enough to do its job. The Khorn was intended to use the walls as the last part of the horn flare. Very few homes have squared corners /plumb walls - haven't found one yet. When your ready to remodel, you can either build the false wall(s) in a more permanent/pretty method or correct the wall you will use. Cheap tweaks: look up Rope Caulking in the forums - this is one of many thing you can do. It made a noticeable difference on my Cornwalls - I used modeling clay from a Frank Van Alstine mod that was popular for stamped frame speakers and horns back in the 80's (Toy's R Us 1.00 per pound). This with the crossovers to remove the sibilance issues may surprise you. Side note: Van Alstine is in Minnesota - opinionated like many in Audio - but does offer some good things if interested

[meagain]

Only one dimension of the future room is known: 28'. The dimension is arbitrary and likely will be dictated by whatever's best for the khorns. I'll be all over those workmen to get those corners straight. []. The rope caulk trick is on my long list for a try down the road. It sounds removeable. If not, I may not try. Going to try to get hubby to come home early. Going to do some listening now in different parts of the room (esp the sweet spot) so I have a good reference for the x-over swap.