Jump to content

A (probably silly) newbie question about a crossover...


Oicu812

Recommended Posts

I was looking at different crossover networks in preparation for building @ClaudeJ1 type "Super Heresys", and I'm not understanding something.  Below is the Heresy type E network, which shows a positive path for the woofer through an inductor, and into the speaker's positive terminal.  But then it shows the positive input being fed into a capacitor, and then through the autoformer to the negative side of the squawker and tweeter.  The second network diagram shows a type AA, where the positive path always goes to the positive terminals. 

 

Why the difference?  (I apologize if this is something so normal that I should know the answer, but I haven't run into the answer in my reading as of yet.)  If there is a beginner primer covering this, I would appreciate any links or feedback.  Thank you in advance!

 

 

 

Heresy I Type E Crossover.jpg

 

 

 

fJDHgPC.jpg

 

 

@JohnA

@jimjimbo

@CECAA850

Link to comment
Share on other sites

10 minutes ago, Deang said:

“Progress isn't made by early risers. It's made by lazy men trying to find easier ways to do something.”

― Robert A. Heinlein

 

 

What a great sig. lol.

 

Thanks!  I do IT Automation for a living, and that quote describes my life perfectly.

Link to comment
Share on other sites

59 minutes ago, CECAA850 said:

Sometimes the signal gets out of phase electronically when it travels through components so the wires are crossed going to the drivers to put it back in phase acoustically.

Actually it's both. since, acoustically, the distance between drivers is uneven. Klipsch did measurements and they found it measured and sounded better with mid and tweet in reverse polarity as a better compromise.

  • Thanks 1
Link to comment
Share on other sites

9 minutes ago, ClaudeJ1 said:

Actually it's both. since, acoustically, the distance between drivers is uneven. Klipsch did measurements and they found it measured and sounded better with mid and tweet in reverse polarity as a better compromise.

 

Thanks for the answer.  I guess I am used to seeing capacitors and resistors on the positive / uphill side of the functional device, and it struck me as “wrong” when tracing from the device back to the origination point.  I will keep reading as much as I can find on the subject.

Link to comment
Share on other sites

37 minutes ago, jimjimbo said:

But just for clarity, you ARE planning on building a Type B network for your Super H's....correct?

 

Correct, a Cornwall "B", as a matter of fact.  I used those two networks to simply illustrate my question.  Woofers are ordered, along with all the caps, wire, and assorted goodies I need.  They are out of stock on the 4" flared tubes, so I picked up the other style of 4" to hold me over until they get more in stock.

Link to comment
Share on other sites

25 minutes ago, Oicu812 said:

 

Correct, a Cornwall "B", as a matter of fact.  I used those two networks to simply illustrate my question.  Woofers are ordered. along with all the caps, wire, and assorted goodies I need.  They are out of stock on the 4" flared tubes, so I picked up the other style of 4" to hold me over until they get more in stock.

Are these the ones your ordered instead?? If so, as PWK used to say: "There's not a dime's worth of difference."  Okay, so maybe a penny, but that's all. No need to get the ones in the original Super Heresy recipe for success.

https://b2b.parts-express.com/speaker-cabinet-port-tube-4-id-x-4-3-8-l--260-411

  • Thanks 1
Link to comment
Share on other sites

1 minute ago, ClaudeJ1 said:

Are these the ones your ordered instead?? If so, as PWK used to say: "There's not a dime's worth of difference."  Okay, so maybe a penny, but that's all. No need to get the ones in the original Super Heresy recipe for success.

https://b2b.parts-express.com/speaker-cabinet-port-tube-4-id-x-4-3-8-l--260-411

 

Those are the exact ones that I ordered.  Thank you for the heads up, I wasn't too sure if the flared version would make any measurable difference in performance.

Link to comment
Share on other sites

14 minutes ago, Oicu812 said:

 

Those are the exact ones that I ordered.  Thank you for the heads up, I wasn't too sure if the flared version would make any measurable difference in performance.

Good. More importantly, in my original Super Heresy thread, I mentioned that I modifies an E network just like YOURS. As far as I can recall, over 4 years ago when I did this, I did NOT actually change to a B network STRICTLY, since I never reversed the mid and tweet polarities back to all positive........................SO, leave those mid and tweet polarities going to the minus as they are. When I discovered, at a much later time, that I had "effectively" created a Cornwall B network, I should have paid closer attention. I would then have discovered that I made an effective B network with the Mid and Tweet Polarities Reversed. My Bad.

 

This should simplify your mod if you follow my original recipe, which modified an E network just like yours with no change in driver polarities!! Cheers!!

 

JimJimbo, please take note of this as you move forward with more mods.

 

PS: I don't know if a B network, with all + polarities would sound any better or worse than my modified E with the - polarities on the horns. It would take a double pole, double throw switch, long wires out of the bass port, a measurement setup, and/or lots of program material and your ears to try and tell the difference. NOT having done this, I can't know for sure. It's up to y'all to do that subtle test and find out if you with to do so. I'm guessing there could be a "dime's worth of difference," but how AUDIBLE it is puts it beyond the scope of this text. At this point in my life, I have no reason to try it. Although I do have a nice Walnut pair of Heresy I's, in the basement that I may put into service as rear channels (along with a mono center front)  for my Jubilee Clones...............decisions, decisions. LOL.

Link to comment
Share on other sites

I am using a Bryston 4B NRB (Latest edition) to drive the Heresies, any opinion on this amp?

https://www.stereophile.com/solidpoweramps/592bryston/index.html

 

This is the system for my office, where I am running digital SPDIF out to an Onkyo TX-SR700 7.1, and using the pre-outs to the Bryston.  If I want to do 2.1, I can turn off all the other speakers and only run the Heresies.  Most of the time, I listen to everything in surround mode:


Front L&R:  KG4's.

Center: Two Quintets into the same center channel, on either side of the monitor angled 45 degrees inward.  They make an awesome "virtual" center. 

Mid L&R: KSF 8.5's.

Back L&R: The Heresies on a pre-out to the Bryston.

Sub: Cheap powered Polk.  I am looking for a reasonably priced Klipsch offering

 

I plan to do one Heresy first, and do a compare with the unaltered version.  It would not take too much more effort to swap polarities on the modded side to see if there is a difference.

 

Link to comment
Share on other sites

18 minutes ago, Oicu812 said:

plan to do one Heresy first, and do a compare with the unaltered version.  It would not take too much more effort to swap polarities on the modded side to see if there is a difference.

Good, if you do exactly what you say, then your test setup is pretty sound, pun intended. Then, please post your impressions and/or measured results on the original Super Heresy thread. I, and many others, would appreciate it. I believe that any audible differences will be subtle and hard to detect, but I leave that up to you.

 

BTW, I used to have KG4's in my car, back in the day. LOL. Back then, my wife had Heresy's in the dining room and my son, (then 12), had Heresy's in his bedroom, while my first daughter had Heresys in hers. My son still has them and so does my Ex Wife. LOL. Hoever, my baby girl married an audiophile, and they have 50 speakers in their house and outdoors (also an 11.4 Atmos HT). What's even funnier is my baby girl, having grown up with Klipsch PRO stuff, like MWM's in the basement thinks that their living room speakers are way to small!! Now, how many Wives have EVER said that to their husbands!! And, she really like my Jubilees as well!! That makes me a proud papa, eh??

Link to comment
Share on other sites

1 minute ago, ClaudeJ1 said:

Good, if you do exactly what you say, then your test setup is pretty sound, pun intended. Then, please post your impressions and/or measured results on the original Super Heresy thread. I, and many others, would appreciate it. I believe that any audible differences will be subtle and hard to detect, but I leave that up to you.

 

BTW, I used to have KG4's in my car, back in the day. LOL. Back then, my wife had Heresy's in the dining room and my son, (then 12), had Heresy's in his bedroom, while my first daughter had Heresys in hers. My son still has them and so does my Ex Wife. LOL. Hoever, my baby girl married an audiophile, and they have 50 speakers in their house and outdoors (also an 11.4 Atmos HT). What's even funnier is my baby girl, having grown up with Klipsch PRO stuff, like MWM's in the basement thinks that their living room speaker are way to small!! That makes me a proud papa, eh??

 

Now that earned an actual "Laugh Out Loud" from me.  That's fantastic!

 

As far as my test impressions go, take any opinion I have with a liberal block of salt.  Having tinnitus has ruined my "critical listening" ability, unfortunately.  I was a pro audio guy back in the day, but having a motorcycle tire blow up inches from my head put an end to all of that.  Nowadays, sound pressure levels trump most everything, with plenty of headroom coming in a close second.

Link to comment
Share on other sites

4 minutes ago, Oicu812 said:

 

Now that earned an actual "Laugh Out Loud" from me.  That's fantastic!

 

As far as my test impressions go, take any opinion I have with a liberal block of salt.  Having tinnitus has ruined my "critical listening" ability, unfortunately.  I was a pro audio guy back in the day, but having a motorcycle tire blow up inches from my head put an end to all of that.  Nowadays, sound pressure levels trump most everything, with plenty of headroom coming in a close second.

Well, then, you should be able to disconnect the tweeters and enjoy the new, superior, bass output!! LOL.

  • Haha 1
Link to comment
Share on other sites

1 hour ago, ClaudeJ1 said:

Good. More importantly, in my original Super Heresy thread, I mentioned that I modifies an E network just like YOURS. As far as I can recall, over 4 years ago when I did this, I did NOT actually change to a B network STRICTLY, since I never reversed the mid and tweet polarities back to all positive........................SO, leave those mid and tweet polarities going to the minus as they are. When I discovered, at a much later time, that I had "effectively" created a Cornwall B network, I should have paid closer attention. I would then have discovered that I made an effective B network with the Mid and Tweet Polarities Reversed. My Bad.

 

This should simplify your mod if you follow my original recipe, which modified an E network just like yours with no change in driver polarities!! Cheers!!

 

JimJimbo, please take note of this as you move forward with more mods.

 

PS: I don't know if a B network, with all + polarities would sound any better or worse than my modified E with the - polarities on the horns. It would take a double pole, double throw switch, long wires out of the bass port, a measurement setup, and/or lots of program material and your ears to try and tell the difference. NOT having done this, I can't know for sure. It's up to y'all to do that subtle test and find out if you with to do so. I'm guessing there could be a "dime's worth of difference," but how AUDIBLE it is puts it beyond the scope of this text. At this point in my life, I have no reason to try it. Although I do have a nice Walnut pair of Heresy I's, in the basement that I may put into service as rear channels (along with a mono center front)  for my Jubilee Clones...............decisions, decisions. LOL.

OK, now I'm confused....as usual.  Claude, would you mind posting a schematic of how the crossover SHOULD be wired.

Link to comment
Share on other sites

We've all danced around the reason but not hit the whole thing.  Per a Dope from Hope, Mr. Paul found reversed polarity measured a little better.  The reason is a horn lags a direct radiator by 90*.  A capacitor also causes a 90* lag.  Together they make 180 and it becomes logical to reverse the phase of one or the other.  A Type AA network was used with all horn speakers so there was no inherent phase difference from low to HF. 

  • Thanks 1
Link to comment
Share on other sites

1 hour ago, jimjimbo said:

OK, now I'm confused....as usual.  Claude, would you mind posting a schematic of how the crossover SHOULD be wired.

Like a modified E, with the exact instructions of desoldering/soldering in the original Super Heresy post. Not like a Cornwall B.

 

If someone buys a Cornwall B instead of modifying an E, the connections on both horns will be at 180 degrees out of phase (more properly, POLARITY) from my original. Not the end of the world, but different from what I actually did on yours.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...