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post #1891 of 1917 Old 01-22-2013, 10:38 AM
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Quote:
Originally Posted by stormwind13 View Post

Those results are on the original, the design has changed twice since then.
I haven't seen the updates on the Dayton 1000. Where can I see them?
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post #1892 of 1917 Old 01-22-2013, 05:52 PM
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Quote:
Originally Posted by LINEARX View Post

Chas w 98 tested the Dayton amp. The results are posted. His tests show it to be a limited amp with max output of 451watts at 40Hz, less at 20 and even less at 10Hz.
I just find it ironic that people slam the Dayton based on a continuous sine wave test when it's specifically rated for it's power on a 1/3rd duty cycle. However, people love the FP 14000 clones which haven't been tested but have a fictitious and imaginary power rating. Testing of a real FP 14000 (not the crap clone everyone is buying) using a test methodology that is less demanding than the continuous sine wave tests chasw98 used show it delivers about 1650W per channel into 4 ohms, not 4400W. I can only imagine even how much less capable the Sanway FP 14000 clones are.
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post #1893 of 1917 Old 01-22-2013, 05:59 PM
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I wasn't a fan of the Dayton because it rolled off below 20hz significantly. If that's changed then... great!

My Dual 18" LLT subs 120dB down to 10hz

 

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post #1894 of 1917 Old 01-22-2013, 06:01 PM
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Quote:
Originally Posted by Scott Simonian View Post

I wasn't a fan of the Dayton because it rolled off below 20hz significantly. If that's changed then... great!
You can fix that with a soldering iron and a few new components.
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post #1895 of 1917 Old 01-22-2013, 06:07 PM
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Originally Posted by Stereodude View Post

You can fix that with a soldering iron and a few new components.

Sure as long as you are are willing and able to do that to your brand new amp.

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post #1896 of 1917 Old 01-22-2013, 06:31 PM
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Originally Posted by jpmst3 View Post

Sure as long as you are are willing and able to do that to your brand new amp.
Well, you can't have everything. There aren't too many other plate amps in the same ballpark power wise and none at the same cost that I'm aware of.
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post #1897 of 1917 Old 01-22-2013, 06:41 PM
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ChasW 98 tests all the amps the same.Those tests are a useful tool to determine which amp is suitable for your own needs.
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post #1898 of 1917 Old 01-22-2013, 09:13 PM
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Quote:
Originally Posted by LINEARX View Post

ChasW 98 tests all the amps the same.Those tests are a useful tool to determine which amp is suitable for your own needs.
Yes, assuming you listen to sine waves.
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post #1899 of 1917 Old 01-22-2013, 09:26 PM
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They're helpful as a basis of comparison on equal footing and to get an idea how much specsmanship may or may not be in play.

Just because there is a knob doesn't mean you should turn it.
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post #1900 of 1917 Old 01-23-2013, 05:57 AM
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Quote:
Originally Posted by whoaru99 View Post

They're helpful as a basis of comparison on equal footing and to get an idea how much specsmanship may or may not be in play.
Yes, but the testing may lead someone to draw an erroneous conclusion because it's not representative of the end use.

For example, you have "1000w" two amps that will perform identically in real world home theater use. One is a lot cheaper than the other. The cheaper one does poorly in a continuous sine wave test, but the other doesn't. Is the more expensive amp really a better amp for home theater use? No, but the test likely leads you to an incorrect conclusion about the amplifier.

To use the obligatory car analogy... How much value would you put in reviews of snow tires that focused on their handling at their max speed rating in hot dry weather?
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post #1901 of 1917 Old 01-23-2013, 06:21 AM
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Originally Posted by Stereodude View Post


To use the obligatory car analogy... How much value would you put in reviews of snow tires that focused on their handling at their max speed rating in hot dry weather?

Depends on what claims the snow tire manufacturer was making.

While I completely understand your implied point about duty cycle, if I'm buying an amp that claims 1kW per channel then I like to know if it can actually do that for more than a microsecond at 50% distortion regardless if I actually need it or not. Once you have this information then you can make the informed decision whether it will meet your needs or not.

Just because there is a knob doesn't mean you should turn it.
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post #1902 of 1917 Old 01-23-2013, 07:56 AM
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Quote:
Originally Posted by Scott Simonian View Post

I wasn't a fan of the Dayton because it rolled off below 20hz significantly. If that's changed then... great!
The Dayton HPSA1000-R tested rolled off 15 dB by 10 Hz with a non-defeatable subsonic filter. The current Dayton SA1000 has an on/off switch for the subsonic filter. With the filter off, the amp is down by about 3 dB at 10 Hz per my testing.
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post #1903 of 1917 Old 01-23-2013, 08:12 AM
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Quote:
Originally Posted by desertdome View Post

With the filter off, the amp is down by about 3 dB at 10 Hz per my testing.
`
Uh oh . . . . there's that problem again, you "tested" . . . . . according to some on this site, only the obligatory "car analogy" will get you to where you want to go.
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post #1904 of 1917 Old 01-23-2013, 08:56 AM
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Quote:
Originally Posted by LINEARX View Post

Uh oh . . . . there's that problem again, you "tested" . . . . . according to some on this site, only the obligatory "car analogy" will get you to where you want to go.
Thanks for publicly admitting in your own special and unique way that you have nothing more of value to add on this topic! smile.gif
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post #1905 of 1917 Old 01-23-2013, 09:07 AM
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Quote:
Originally Posted by whoaru99 View Post

Depends on what claims the snow tire manufacturer was making.

While I completely understand your implied point about duty cycle, if I'm buying an amp that claims 1kW per channel then I like to know if it can actually do that for more than a microsecond at 50% distortion regardless if I actually need it or not. Once you have this information then you can make the informed decision whether it will meet your needs or not.
I will admit it would be nice if Dayton would specify a time base for the 1/3 duty cycle. It points to thermal limitations, but it is unknown how long it will drive 950W for before they kick in. My expectation is that that the latest version can drive 950W for seconds, not ms or us. You just can't heat up the amount of metal on the back of the amp in ms and trigger some sort of thermal protection that quickly. There aren't thermal diodes in the output transistors to give near instant thermal feedback. Ultimately, we don't know because Dayton isn't saying (they may not know) and no one has tested it. What we can infer is that the version of the amp chasw98 tested throttled itself back to under 500W after it heated up.
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post #1906 of 1917 Old 01-23-2013, 05:17 PM
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Quote:
Originally Posted by Stereodude View Post

Quote:
Originally Posted by whoaru99 View Post

Depends on what claims the snow tire manufacturer was making.

While I completely understand your implied point about duty cycle, if I'm buying an amp that claims 1kW per channel then I like to know if it can actually do that for more than a microsecond at 50% distortion regardless if I actually need it or not. Once you have this information then you can make the informed decision whether it will meet your needs or not.
I will admit it would be nice if Dayton would specify a time base for the 1/3 duty cycle. It points to thermal limitations, but it is unknown how long it will drive 950W for before they kick in. My expectation is that that the latest version can drive 950W for seconds, not ms or us. You just can't heat up the amount of metal on the back of the amp in ms and trigger some sort of thermal protection that quickly. There aren't thermal diodes in the output transistors to give near instant thermal feedback. Ultimately, we don't know because Dayton isn't saying (they may not know) and no one has tested it. What we can infer is that the version of the amp chasw98 tested throttled itself back to under 500W after it heated up.

Snell rated their rebadge of the SA1000 as a 750W continuous amp.

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post #1907 of 1917 Old 01-23-2013, 11:14 PM
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Parts Express has some "Reviews" of the SPA 1000. Read through those and see if your experience matches theirs.
Then let us know what you think.
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post #1908 of 1917 Old 01-24-2013, 12:37 PM
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Here is my experience in testing the SA1000 against the Inuke DSP 3000 on a pair of CHT 18.1 subs. The Inuke was running the subs at 8ohm stereo. The SA1000 was running the subs in 4ohm bridged. The Inuke had significantly more output and tactile feel both with and without audyssey.

http://www.avsforum.com/t/1387178/archaeas-kansas-city-blind-subwoofer-shootout-2012/340_20#post_21515107


I felt the Inuke DSP 3000 had significantly more umpf down low than the Dayton amp did on the same pair of drivers when compared back to back. Also the 25hz bass boost isn't so much a 25hz bass boost as a gain increase across the spectrum on the SA1000 I tested. I personally thought the SA1000 was a fairly weak amp in my limited experience.

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post #1909 of 1917 Old 04-27-2013, 07:59 AM
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Being that this is the best amp review thread I have come across I am posting this here. Let me know If I should just start a new thread to ask my question if this deosn't belong here. Thanks!

I'm kinda a slacker some times, but searching this thread yielded zero hits and I have only read to post # 171 at this point. I am going to continue reading this entire thread because of all the usefull info presented here. So, thank you to everyone who has contributed useful information.

What I am looking for is information on a pair of amps I have, as to whether I should try and use them for sub duty (on 4 Dayton UM15's I just bought) or donate them, as they are in working condition, to a church or some other usefull home.

What I have is a pair of EV (Altec Lansing made) AP2600A amps.

The same as seen here http://www.ebay.com/itm/290581207425?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

I bought these to use as sub amps for a while and then use them for main channel amps when I buy more powerful sub amps. (My AVR has 7.2 pre out's)

I haven't found much useful info on these other than the owners manual and the rated info which is listed in the ebay auction.

Have these been tested anywhere or does anyone have any useful information about these amps? Info listed in ebay auction is displayed below for reference when the linked listing becomes invalid:

THE SPECS ON THE AMPLIFIER ARE:

3 Rack Spaces

OUTPUT POWER:

Dual Mode 8 ohms 200 watts

Dual Mode 4 ohms 300 watts

Bridged Mode 80 ohms 600 watts

DIMENSIONS:

Depth 12.8 inches

19" wide

3 rack spaces

WEIGHT:

43 pounds - shipping weight

OCTAL SOCKETS ON THE REAR PANELS ACCEPT PLUG IN MODULES FOR CROSSOVER, SIGNAL DELAY AND EQ (plug in are not included in this sale)

OUTPUTS: Terminal Strip

INPUTS: XLR

with level controls for each channel

with cooling fan's

MADE IN THE U.S.A.
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post #1910 of 1917 Old 04-27-2013, 08:40 AM
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Assuming it's just a relabeled 9400 series Altec, then its specs are good enough for a mainstream studio reference system and/or at high power for long periods of time in a PA app, but for sub duty its 10 Hz F3 plus generally noisy fan may be a deal breaker for some.

GM

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post #1911 of 1917 Old 04-28-2013, 05:46 AM
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Quote:
Originally Posted by GPM View Post

Assuming it's just a relabeled 9400 series Altec, then its specs are good enough for a mainstream studio reference system and/or at high power for long periods of time in a PA app, but for sub duty its 10 Hz F3 plus generally noisy fan may be a deal breaker for some.

GM

Thank you for the info. So they will be useful for the mains but not so much for the subs. They aren't powerful enough for sub duty anyway, but I may use them that way for a little anyway. Is there a known popular option for a fan replacement in an amp like these? Thanks again.
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post #1912 of 1917 Old 04-28-2013, 12:51 PM
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You're welcome! There's a general thread here about swapping out fans, but haven't bothered to scope out what the options for this amp would be.

My 9444A has been 'bulletproof' for ages even though I disconnected the fan and turned it up on end on top of a couple of 2x4 scrap wood spacers and left the case a little loose to allow heat to dissipate. It's powerful, been durable enough for my two dual H.E. 15" subs tuned to ~16 Hz, but then they are corner pipe horn loaded [~20 ft^3/ea.] to keep efficiency high, so only need to put out the 150 W/8 ohm combined parallel driver rating + the small amount the HF horns require and even then only on really low LFE when cranked up to DD/THX reference. Average power required for the 85 dB reference at the Lp is only 0.03-0.05 W, so normally has plenty of cooling time.

GM

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post #1913 of 1917 Old 05-02-2013, 06:45 AM
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Originally Posted by GPM View Post

You're welcome! There's a general thread here about swapping out fans, but haven't bothered to scope out what the options for this amp would be.

My 9444A has been 'bulletproof' for ages even though I disconnected the fan and turned it up on end on top of a couple of 2x4 scrap wood spacers and left the case a little loose to allow heat to dissipate. It's powerful, been durable enough for my two dual H.E. 15" subs tuned to ~16 Hz, but then they are corner pipe horn loaded [~20 ft^3/ea.] to keep efficiency high, so only need to put out the 150 W/8 ohm combined parallel driver rating + the small amount the HF horns require and even then only on really low LFE when cranked up to DD/THX reference. Average power required for the 85 dB reference at the Lp is only 0.03-0.05 W, so normally has plenty of cooling time.

GM

That's encouraging news to me. Thanks for the additional info. My AVR seems to just begin to drive my speakers as 2 channel and is just as week when spreading power across all channels for music. It can't drive the front and rears to much authority at all, and before getting to a level approaching loud there is tons of audible distortion detectable. I know that my speakers are not that taxed, but I do have quite a bit of cone to move. My main channels have to drive the fronts with two 8", a 5" and a tweeter each, while the rears (which were the fronts until recently when I found that they tonally matched the center a little less than the current fronts) have a 12", 5" and a 3" tweeter. When driving either the front speakers or rear speakers alone the built in amp just has no balls, let alone trying to drive all of them at once.

Just as a test of the amps I am going to hook them up some time soon to drive the front and rear speakers. The added power should really liven things up and allow for greater volume with less distortion and some much needed head room. i'll raid my PC closet for some fans to see if I have something low noise to put in there even though you have had good results running yours fanless. I would hate for these things to cook themselves as I don't have much top to bottom shelf clearance for convective heat transfer.

I am guessing that I should buy a EP4K to run the subs. for just $380 It would be a good start for sub amps as far as I can tell, although it will be under powered for driving the subs to their max potential as I should have 3200 watts to drive them to their rated max...
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post #1914 of 1917 Old 03-06-2014, 04:24 AM
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I have a question regarding measuring Voltage out from Amplifiers.

My sealed subs are powered by a EPX4000 each and they are bridged.

The drivers itself is 4Ohms, but in WinISD simulation, they go as low as 3.6Ohm.
In addition at a given frequency the ohm rises to over 15ohms.

Is it possible to do a sine sweep at a given frequency and find the right resistance so I can calculate how much watts beeing used?
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post #1915 of 1917 Old 03-06-2014, 02:57 PM
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Quote:
Originally Posted by Strike Ace View Post

I have a question regarding measuring Voltage out from Amplifiers.

My sealed subs are powered by a EPX4000 each and they are bridged.

The drivers itself is 4Ohms, but in WinISD simulation, they go as low as 3.6Ohm.
In addition at a given frequency the ohm rises to over 15ohms.

Is it possible to do a sine sweep at a given frequency and find the right resistance so I can calculate how much watts beeing used?
Just use the Amplifier Apparent Load Power view in WinISD. Here is my 8x IB15 system with 4000 watts. You can see how little power the drivers get at low frequencies and how my system stays within its excursion limits.



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post #1916 of 1917 Old 03-14-2014, 10:16 AM
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Nice thank you. I have always attempted to run these types of amp through a 220 distro with 30 amp and min 10 awg wiring for max electric power. Do you have any info to calculate the "sag" ?

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post #1917 of 1917 Old 03-14-2014, 11:44 AM
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Quote:
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Do you have any info to calculate the "sag" ?
V=IR
There are any number of voltage drop calculators available online.
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