Measuring Amplifiers - Page 36 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #1051 of 1917 Old 06-07-2008, 07:22 AM
Senior Member
 
LINEARX's Avatar
 
Join Date: May 2007
Location: Pottsboro, Texas
Posts: 323
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by penngray View Post

Im waiting for a new fan to mod my QSC so when Im done and back from a business trip, I will send them both off to Chuck in ONE heavy box

I was gonna suggest that, two for the price of one . . . . . or something.
LINEARX is offline  
Sponsored Links
Advertisement
 
post #1052 of 1917 Old 06-07-2008, 07:34 AM
Senior Member
 
LINEARX's Avatar
 
Join Date: May 2007
Location: Pottsboro, Texas
Posts: 323
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by TheEAR View Post

...

Today I let the XTi2000 and XTi4000 pound out the bass,both test tones and some Whack a Ton music used to demonstrate high SPL 150dB + car systems.


I will not attempt this again,my ears pulsate. The XTi2000 has enough juice in the trunk.XTi2000/4000 users should not worry too much about any lack of power.
...

Hey Ear,
I forget what other amps you have but since Chuck found an issue with the XTi 1000 and you have just done an unofficial test of your own on the 2000 and 4000, do you now think the 1000 tested by Chuck was an anomaly?
Also if you have other amps how do the XTis compare with those for power in a listening test?
LINEARX is offline  
post #1053 of 1917 Old 06-07-2008, 07:59 AM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
I missed that post from TheEar, its great to hear that the Xti products do well. TundrSQ already posted he was happy with his amp and I still have the Dayton 1000W amp in use so measurements doesn't always dictate performance and Im cool with that!

It also proves that we dont really need HUGE measured Watts to produce insane SPL....I seldom actually do 110dB these days

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #1054 of 1917 Old 06-07-2008, 08:18 AM
Senior Member
 
LINEARX's Avatar
 
Join Date: May 2007
Location: Pottsboro, Texas
Posts: 323
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
How much power (watts) do we actually need? Good question. Some say you need gobs and gobs and never have enough headroom. But really how often are we even allowed to crank it up with neighbors and family always being the limiting factor. I myself play loud but I don't think I have the sub over 105db and then that's only when I'm into some of the baddest DVDs. My opinion . . . . . around a 1000 watts of good clean power is enough including those times when there are cannons or earthquakes or Clingons or even synthesizers to reproduce. I don't want to be called "Insane in the membrane".
LINEARX is offline  
post #1055 of 1917 Old 06-07-2008, 08:30 AM
AVS Special Member
 
SteveCallas's Avatar
 
Join Date: Jun 2004
Posts: 6,714
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 17
penngray, with a 16hz tuning, that rolloff does NOT seem natural, it is way too steep.

Quote:


How much power (watts) do we actually need?

As much as you are willing to pay for. You still want gobs of power, but you don't need it in the form of a continuous sine wave, you need it in short bursts.
SteveCallas is offline  
post #1056 of 1917 Old 06-07-2008, 09:19 AM
AVS Special Member
 
TheEAR's Avatar
 
Join Date: Nov 2006
Location: Montreal,CANADA
Posts: 3,464
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by LINEARX View Post

Hey Ear,
I forget what other amps you have but since Chuck found an issue with the XTi 1000 and you have just done an unofficial test of your own on the 2000 and 4000, do you now think the 1000 tested by Chuck was an anomaly?
Also if you have other amps how do the XTis compare with those for power in a listening test?


Anomaly...no I think these amps weak point is sustained output below ~50Hz.

On short bursts they do much better. I did not sense a weakness driving TC3000 and LMS-Ultra sealed,I did not push the drivers or amps that much.

A normal user will not complain of a performance issue,tests push amps much harder than anyone here will.

Ask yourself mortal , do you have as much displacement as me ? The answer is no unless you have a Windmere fan sub.
TheEAR is offline  
post #1057 of 1917 Old 06-07-2008, 12:49 PM
Senior Member
 
AlexE's Avatar
 
Join Date: Feb 2008
Location: Southern Cali, SD area
Posts: 440
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I love the different replies for "how much power do we need?"

How about 'whatever your drivers need'

If you have a single ported 12 you wont need what you'll need with quad 18s in a small sealed box...
AlexE is offline  
post #1058 of 1917 Old 06-07-2008, 12:58 PM
AVS Special Member
 
deneb's Avatar
 
Join Date: Mar 2007
Location: Pac NW, Seattle area
Posts: 1,089
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by LINEARX View Post

How much power (watts) do we actually need? Good question. Some say you need gobs and gobs and never have enough headroom. But really how often are we even allowed to crank it up with neighbors and family always being the limiting factor. I myself play loud but I don't think I have the sub over 105db and then that's only when I'm into some of the baddest DVDs. My opinion . . . . . around a 1000 watts of good clean power is enough including those times when there are cannons or earthquakes or Clingons or even synthesizers to reproduce. I don't want to be called "Insane in the membrane".


What about Klingon synthesizers during an earthquake?
deneb is offline  
post #1059 of 1917 Old 06-07-2008, 01:11 PM
AVS Special Member
 
TheEAR's Avatar
 
Join Date: Nov 2006
Location: Montreal,CANADA
Posts: 3,464
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by AlexE View Post

I love the different replies for "how much power do we need?"

How about 'whatever your drivers need'

If you have a single ported 12 you wont need what you'll need with quad 18s in a small sealed box...



With an effective ported 50W may be used ,in a compact sealed 1KW may not be enough to reach the same SPL.

I need a truck load of 15 and 18" drivers and a second truck with amps.

Just to be on the safe side when playing some pathetic low rent block buster hoopla loaded trash a ton.


Ask yourself mortal , do you have as much displacement as me ? The answer is no unless you have a Windmere fan sub.
TheEAR is offline  
post #1060 of 1917 Old 06-07-2008, 01:35 PM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:
penngray, with a 16hz tuning, that rolloff does NOT seem natural, it is way too steep.

really, -3 dB at 16 Hz is what WinISD says and that chart shows the same plot, doesnt it?

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #1061 of 1917 Old 06-07-2008, 03:46 PM
AVS Special Member
 
SteveCallas's Avatar
 
Join Date: Jun 2004
Posts: 6,714
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 17
How about the 36db drop in less than one octave below tuning?
SteveCallas is offline  
post #1062 of 1917 Old 06-07-2008, 03:56 PM - Thread Starter
AVS Special Member
 
chasw98's Avatar
 
Join Date: Dec 2004
Location: Margate, FL
Posts: 1,085
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by NEO Dan View Post

The amp's response can be measured with REW right?

I'll try to measure my K1


Without voltage dividers do not try it with anything near full power. Maybe a couple of watts but be careful. Easy to overload the sound card input.
chasw98 is offline  
post #1063 of 1917 Old 06-07-2008, 04:01 PM
Senior Member
 
rodH's Avatar
 
Join Date: Apr 2002
Location: socal
Posts: 315
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by penngray View Post

I missed that post from TheEar, its great to hear that the Xti products do well. TundrSQ already posted he was happy with his amp and I still have the Dayton 1000W amp in use so measurements doesn't always dictate performance and Im cool with that!

It also proves that we dont really need HUGE measured Watts to produce insane SPL....I seldom actually do 110dB these days

Has anyone reviewed the Dayton 1000w rack amp? I just got my dad one for a great deal on ebay from Parts Express. I had an "extra" velodyne SC12 that he is going to use with it in a vacation home. Any opinions on the Dayton 1000w Rack amp?
rodH is offline  
post #1064 of 1917 Old 06-07-2008, 04:09 PM
AVS Special Member
 
Tack's Avatar
 
Join Date: Mar 2004
Location: Valencia, Ca
Posts: 3,194
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 105 Post(s)
Liked: 625
Scroll down a couple posts.


Or don't , if you're happy with it.....

http://www.avsforum.com/avs-vb/showt...9#post13714349
Tack is offline  
post #1065 of 1917 Old 06-07-2008, 04:54 PM
Senior Member
 
rodH's Avatar
 
Join Date: Apr 2002
Location: socal
Posts: 315
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Tack View Post

Scroll down a couple posts.


Or don't , if you're happy with it.....

http://www.avsforum.com/avs-vb/showt...9#post13714349

INteresting, so 450w @ 8 ohms and 580w @ 4 ohms? I have not even hooked it up yet, but since the driver he is using is an 8 ohm, it is rated at about 500w there, and it looks like it only puts out 450w, not too bad. Wonder why it doesn't produce more power in 4 ohms?
rodH is offline  
post #1066 of 1917 Old 06-07-2008, 04:58 PM - Thread Starter
AVS Special Member
 
chasw98's Avatar
 
Join Date: Dec 2004
Location: Margate, FL
Posts: 1,085
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by penngray View Post

We aren't its a measured amp and nothing else is going on someone should fork over some dough and send more amps to chuck. $60 is worth it to get your amps measured!!

I was searching to see if any QSCs have been measured, I might send my QSC 1850HD next and maybe one of my Outlaw monoblocks (its not a sub amp but I really like them and Im curious!)

If you are that hungry for pictures and tests, then I should probably do my Bryston, my Aragon, my 'modded' Haflers, and my Cinenova while I do your Outlaw and QSC. And I have already done my QSC PLX3402! Just give me some notice.
chasw98 is offline  
post #1067 of 1917 Old 06-07-2008, 05:11 PM
Senior Member
 
rodH's Avatar
 
Join Date: Apr 2002
Location: socal
Posts: 315
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Interesting in that thread regarding the Dayton, people praising Bob Carver. I have always thought of Bob Carver as a Mid-Fi company, when his super high rated amps and subs came out, they were ALL the hype, with mid-fi shops. The super high end guys would tell you to go pick up the Carver amp and pick up the Levinson, Krell, or McIntosh amp at the same power, and say "you tell me if that is a true ......watts". I have never felt like Bob Carver stuff was the pinnacle of audio amplification, even though that it is rep amoung mid-fi groupies.
rodH is offline  
post #1068 of 1917 Old 06-07-2008, 05:14 PM
Senior Member
 
LINEARX's Avatar
 
Join Date: May 2007
Location: Pottsboro, Texas
Posts: 323
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
That's quite a list of amps Chuck. I'd be interested in seeing the test results of your modded Hafler, I've got the Hafler 280K that I had used bridged.
LINEARX is offline  
post #1069 of 1917 Old 06-08-2008, 03:36 AM - Thread Starter
AVS Special Member
 
chasw98's Avatar
 
Join Date: Dec 2004
Location: Margate, FL
Posts: 1,085
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
I have now added a master index to all amp tests in the first post of the thread.
chasw98 is offline  
post #1070 of 1917 Old 06-08-2008, 04:32 AM
Senior Member
 
LINEARX's Avatar
 
Join Date: May 2007
Location: Pottsboro, Texas
Posts: 323
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by chasw98 View Post

I have now added a master index to all amp tests in the first post of the thread.

Excellent! We're all going to become as thoroughly knowledgeable about amp stats as you and thylantr! LOL NOT!
LINEARX is offline  
post #1071 of 1917 Old 06-08-2008, 08:18 AM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:


INteresting, so 450w @ 8 ohms and 580w @ 4 ohms? I have not even hooked it up yet, but since the driver he is using is an 8 ohm, it is rated at about 500w there, and it looks like it only puts out 450w, not too bad. Wonder why it doesn't produce more power in 4 ohms?

Yeah, its very weird...Im using it @ 8 ohms so its not a big deal to me.

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #1072 of 1917 Old 06-08-2008, 08:20 AM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:


my Bryston, my Aragon, my 'modded' Haflers, and my Cinenova

Now thats some $$$!!!

Do you believe that these are better amps then the lower end amps like Outlaw or Emotiva? I wonder what the tests show.

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #1073 of 1917 Old 06-08-2008, 01:23 PM
AVS Special Member
 
thylantyr's Avatar
 
Join Date: May 2004
Posts: 3,887
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 18
Quote:
Originally Posted by chasw98 View Post

I have now added a master index to all amp tests in the first post of the thread.


AVS forum is still in the dark ages. Links to threads eventually go dead
as AVS archives their data. You might want to complile your data
into a simple document and host it elsewhere



The storm was gone, but dark clouds still hung around
The perfect setting for things to come......

thylantyr is offline  
post #1074 of 1917 Old 06-08-2008, 04:15 PM
Senior Member
 
rodH's Avatar
 
Join Date: Apr 2002
Location: socal
Posts: 315
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Interesting. I just reviewed the links to all the different amps, amazing that some can be sooooo overrated. I would think that they might be a bit overrated, but nothing more than +/- 10% of claimed power.

I guess my velodyne is a pretty decent amp after all (I knew it had the power section that is used on the highly touted 18" sealed DD18).

I got to thinking, and this is a basic question that I should understand, if it produces approx 1000w in 4 ohms, and I am running 2 drivers and the amp is seeing 4 ohms, does this mean that EACH driver gets 1/2 that power at 500W or each driver gets 1000w? Like a said, a basic question that at one time I knew, but for some reason I forgot.

Thanks
rodH is offline  
post #1075 of 1917 Old 06-08-2008, 06:05 PM
Senior Member
 
LINEARX's Avatar
 
Join Date: May 2007
Location: Pottsboro, Texas
Posts: 323
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Sometimes it's best to forget because if you remember but incorrectly you're gonna end up in a squabble with another poster over some insignificant unimportant detail. Just take those things you remember best and be happy, kiss your wife once in a while and call it a day.
LINEARX is offline  
post #1076 of 1917 Old 06-08-2008, 07:01 PM
Senior Member
 
rodH's Avatar
 
Join Date: Apr 2002
Location: socal
Posts: 315
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by LINEARX View Post

Sometimes it's best to forget because if you remember but incorrectly you're gonna end up in a squabble with another poster over some insignificant unimportant detail. Just take those things you remember best and be happy, kiss your wife once in a while and call it a day.


LOL. Thanks

So what is the answer, does each driver get 500w or 1000w??
rodH is offline  
post #1077 of 1917 Old 06-08-2008, 07:15 PM
Advanced Member
 
2100's Avatar
 
Join Date: Mar 2008
Location: Singapore
Posts: 729
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by thylantyr View Post

AVS forum is still in the dark ages. Links to threads eventually go dead
as AVS archives their data. You might want to complile your data
into a simple document and host it elsewhere

Fortunately I believe google can dig out the archives (as well as audioasylum's), i tried that before. I found some info from you as far back as 2002.
2100 is offline  
post #1078 of 1917 Old 06-08-2008, 09:08 PM
Advanced Member
 
Jack Hidley's Avatar
 
Join Date: Apr 2003
Location: Danville, CA
Posts: 628
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
500w

Jack Hidley
Jack Hidley is offline  
post #1079 of 1917 Old 06-09-2008, 09:25 AM
AVS Special Member
 
Join Date: Mar 2003
Posts: 4,509
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Liked: 606
Quote:
Originally Posted by SteveCallas View Post

How about the 36db drop in less than one octave below tuning?

I've attached the posted graph with what's happening to the response after the room's influence vs an ideal 4th order roll off with an F3 of 16Hz.

It looks like there is some room gain around tune and a null (or signal chain roll off) just above 10Hz. Every room I've ever measured has room gain below 10Hz. When the measurement is expanded to below 10Hz, there is always a bump of some size, regardless of how far down the subwoofer has rolled off by then.

Bosso
LL
bossobass is offline  
post #1080 of 1917 Old 06-09-2008, 10:17 AM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:


does this mean that EACH driver gets 1/2 that power at 500W or each driver gets 1000w?

Each driver will get 500W....make sure your total ohms is 4 and not 2!!

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
Reply DIY Speakers and Subs

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off