• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Review and Measurements of Crown XLS 1502 Amp

Blumlein 88

Grand Contributor
Forum Donor
Joined
Feb 23, 2016
Messages
20,524
Likes
37,057
No, we are stuck in lousy English system. The reason I use degree C is because electronic part ratings are always in degree C so we (electrical engineers) are used to thinking in that scale.
The English system could have been good. Had it stayed with doubling measures it would have been almost like digital bits.

But 2 cups equal a pint.
2 pints equal a quart.
4 quarts equal a gallon.
Well not quite what you wanted is it.

How many pecks in a bushel? 4 pecks of course.
How much is a peck? Why 2 dry gallons. (used for grain and beans and peas).

320 rods in a mile. And a rod is a convenient 16.5 feet. Not to think of yards (5.5 yards in a rod). 1760 yards in a mile.

See it is all very simple.

Acres did anyone want to talk about acres? Originally defined as one chain by one furlong. (66ft x 660ft). Or 43,560 ft squared. Very simple.

I grew up in the USA with all these odd measures. But fell in love with the metric system at age 8. However, I can do most any conversion by remembering that 2.54 cm= 1 inch exactly. The only exact metric to english conversion. And that a 1 cm cubed of water equals one gram. Those two with knowledge of the old English system lets you do all the conversions. (I'll conveniently not mention slugs though I learned them in engineering course work 32.16 and all that)

So I ask you, especially all of you from outside the USA, is the English system lousy???? IS IT????

Oh, and need I mention Imperial gallons vs US gallons. US gallons are 231 cubic inches. Or maybe imperial tons to US tons? Oh did I forget to mention tons. Well never mind.

:facepalm:;):mad::p:cool:


PS- 212 F degrees for boiling and a convenient 32 F degrees for freezing is very simple to remember when that is all you heard about. 0 degrees F is lots colder than 0 degrees C. Who is Lord Kelvin anyway?

PPS- fluid ounces actually almost make sense. I'll leave that as an exercise for the reader. :rolleyes:
 
Last edited:

Pillars

Active Member
Joined
Aug 21, 2018
Messages
291
Likes
216
Not too bad on the performance front for this amp. I bought a busted box new XLS2502 in the $200 range quite some time ago that has been a total tank.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,370
Likes
234,407
Location
Seattle Area
So I ask you, especially all of you from outside the USA, is the English system lousy???? IS IT????
Yeh, try to do woodworking and divide dimensions and see how far you get. :) 1/3 of 23.25 inches is what???? I have cut so many board wrong because I took 3.75 for 3.25 stuff like that....
 

RayDunzl

Grand Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
13,201
Likes
16,983
Location
Riverview FL

RayDunzl

Grand Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
13,201
Likes
16,983
Location
Riverview FL
1/3 of 23.25 inches is what?

No need to be irrational there.

1/3 of 23.25 = 7 3/4 inches.

What's 1/3 of a meter?

333.333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333 nevermind
 

rajapruk

Senior Member
Forum Donor
Joined
Sep 22, 2018
Messages
472
Likes
489
I wonder if decimal time and dates would have been any practical benefit? I know France tried that after the revolution, but it never succeded.
 

Frank Dernie

Master Contributor
Forum Donor
Joined
Mar 24, 2016
Messages
6,445
Likes
15,780
Location
Oxfordshire
The English system could have been good. Had it stayed with doubling measures it would have been almost like digital bits.

But 2 cups equal a pint.
2 pints equal a quart.
4 quarts equal a gallon.
Well not quite what you wanted is it.

How many pecks in a bushel? 4 pecks of course.
How much is a peck? Why 2 dry gallons. (used for grain and beans and peas).

320 rods in a mile. And a rod is a convenient 16.5 feet. Not to think of yards (5.5 yards in a rod). 1760 yards in a mile.

See it is all very simple.

Acres did anyone want to talk about acres? Originally defined as one chain by one furlong. (66ft x 660ft). Or 43,560 ft squared. Very simple.

I grew up in the USA with all these odd measures. But fell in love with the metric system at age 8. However, I can do most any conversion by remembering that 2.54 cm= 1 inch exactly. The only exact metric to english conversion. And that a 1 cm cubed of water equals one gram. Those two with knowledge of the old English system lets you do all the conversions. (I'll conveniently not mention slugs though I learned them in engineering course work 32.16 and all that)

So I ask you, especially all of you from outside the USA, is the English system lousy???? IS IT????

Oh, and need I mention Imperial gallons vs US gallons. US gallons are 231 cubic inches. Or maybe imperial tons to US tons? Oh did I forget to mention tons. Well never mind.

:facepalm:;):mad::p:cool:


PS- 212 F degrees for boiling and a convenient 32 F degrees for freezing is very simple to remember when that is all you heard about. 0 degrees F is lots colder than 0 degrees C. Who is Lord Kelvin anyway?

PPS- fluid ounces actually almost make sense. I'll leave that as an exercise for the reader. :rolleyes:
Being pedantic what is referred to in the USA as the English system isn’t. The Imperial system, which was used in the United Kingdom until 1968 is different from the system used in the USA in several ways, a bit like the language and spelling.
For example the “cup” is afaik a purely US measure, not used in the UK, in baking dry units were measured by weight and liquids in pints and ounces, never “cups”, for example.
The Imperial gallon is bigger than a US gallon, 20 fl oz instead of 16.
We officially went to the SI units system in 1968 but a lot of older people still use stones for their weight (nobody would give their weight in pounds) though I have used kg myself for decades.
Farmers mainly still talk acres rather than hectares, speeds are still in mph on road signs and distances in miles (or yards for short distances).
Many older people still use farenheit when checking the weather, I don’t.
The differences are minor, but the measurement system and language used in the USA are not strictly “English”
 

Frank Dernie

Master Contributor
Forum Donor
Joined
Mar 24, 2016
Messages
6,445
Likes
15,780
Location
Oxfordshire
I wonder if decimal time and dates would have been any practical benefit? I know France tried that after the revolution, but it never succeded.
When I worked in France I always joked that France had a decimal year.
There are so many people on holiday and May and August nothing much gets achieved...
 

Purité Audio

Master Contributor
Industry Insider
Barrowmaster
Forum Donor
Joined
Feb 29, 2016
Messages
9,051
Likes
12,150
Location
London
There isn’t a great deal achieved in the other ten months.
Keith
 

andreasmaaan

Master Contributor
Forum Donor
Joined
Jun 19, 2018
Messages
6,652
Likes
9,399
Oddly enough, in Australia where the imperial system was abandoned in around 1968 too, the only indices IME that routinely continue to be thought of in feet/inches are human height, loudspeaker transducer diameter, and ***** length.
 

Timbo2

Senior Member
Joined
Feb 27, 2018
Messages
497
Likes
396
Location
USA
Being pedantic what is referred to in the USA as the English system isn’t. The Imperial system, which was used in the United Kingdom until 1968 is different from the system used in the USA in several ways, a bit like the language and spelling.
For example the “cup” is afaik a purely US measure, not used in the UK, in baking dry units were measured by weight and liquids in pints and ounces, never “cups”, for example.
The Imperial gallon is bigger than a US gallon, 20 fl oz instead of 16.
We officially went to the SI units system in 1968 but a lot of older people still use stones for their weight (nobody would give their weight in pounds) though I have used kg myself for decades.
Farmers mainly still talk acres rather than hectares, speeds are still in mph on road signs and distances in miles (or yards for short distances).
Many older people still use farenheit when checking the weather, I don’t.
The differences are minor, but the measurement system and language used in the USA are not strictly “English”

Many years ago I forced the Wall Street Journal to print a correction after they wrote an article questioning why a UK model Ford automobile got so much better gas mileage compared to the one sold in the US. I pointed out that the "gallon" figure they pulled from the Ford UK site was an Imperial gallon.
 

Sal1950

Grand Contributor
The Chicago Crusher
Forum Donor
Joined
Mar 1, 2016
Messages
14,073
Likes
16,609
Location
Central Fl
Sal will surely tell you there's no substitute for cubic inches.
You know me so well. LOL
Yes the system is a bit wonky, but we love it. :)
Only thing I don't agree on is farenheit vs celcius
Celcius in no way to me relates to what people feel in the way of temperature change, unless you use decimals.
80f is 26c 32 is 0? Goes from warm to freezing in a big hurry.

Besides if you were a poor mechanic like me and had to buy about $5k of new tools when the geniuses ordained we had to change to metric
you weren't too happy at the time.
Plus all the old brit cars & bikes using whitworth, that made 3 set of wrenches.
 

andreasmaaan

Master Contributor
Forum Donor
Joined
Jun 19, 2018
Messages
6,652
Likes
9,399
You know me so well. LOL
Yes the system is a bit wonky, but we love it. :)
Only thing I don't agree on is farenheit vs celcius
Celcius in no way to me relates to what people feel in the way of temperature change, unless you use decimals.
80f is 26c 32 is 0? Goes from warm to freezing in a big hurry.

Besides if you were a poor mechanic like me and had to buy about $5k of new tools when the geniuses ordained we had to change to metric
you weren't too happy at the time.
Plus all the old brit cars & bikes using whitworth, that made 3 set of wrenches.

This is a joke right? ;)

Can you feel the difference between 80 and 81 deg Fahrenheit? Are that many gradations really necessary?

1 deg Celsius is about the minimum perceptible change in ambient temp (based on nothing but my flawed and biased personal experience).
 

Sal1950

Grand Contributor
The Chicago Crusher
Forum Donor
Joined
Mar 1, 2016
Messages
14,073
Likes
16,609
Location
Central Fl
Can you feel the difference between 80 and 81 deg Fahrenheit? Are that many gradations really necessary?
Yes I think so, Not 1 but 2 degrees, in the water, you bet.
We have a on-going contest at the swimming pool here and I can consistently call the water temp within 2 degrees after a few minutes to acclimate.
 

RayDunzl

Grand Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
13,201
Likes
16,983
Location
Riverview FL
Getting back somewhere that might be closer to the topic, which "measurement system/s" is/are in use when we measure the performance of our audio appliances?
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,370
Likes
234,407
Location
Seattle Area
Getting back somewhere that might be closer to the topic, which "measurement system/s" is/are in use when we measure the performance of our audio appliances?
SI system.
 

RayDunzl

Grand Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
13,201
Likes
16,983
Location
Riverview FL

Ron Texas

Master Contributor
Joined
Jun 10, 2018
Messages
6,078
Likes
8,914
Analog inputs only...

Features:

Expanded DSP with Band Pass filters

https://3e7777c294b9bcaa5486-bc9563.../5055568_XLSDC2_MNL_PRINT_050615_original.pdf

I am hesitant to say there is a digital signal processor inside the box based on the documentation. They only use the abbreviation "DSP" and it is shown as "DSP capabilities" or "DSP functionality". I personally think it is weasel worded as lawyers say. Amir has made an educated guess. The 24 khz brick wall filter is a fact. To me going from A to D and back again seems like a lot of complications. There is no digital input, but that could be a cost cutting measure. My uneducated guess, and it could be silly, is frequency response is being altered in the PWM process. Honestly, I don't know if there is a good way to set up band pass filters in the PWM process. It does not change the somewhat middling test results.
 
Top Bottom