Switching to Class A/B for Subs?

[Justintoxicated 10+ year member]

Well Since this is going in a Titan(not a car) that will soon have an intake I doubt I will be hearing the fan, but then again my truck is very quiet!. Amps should go under the seat as well.

I just won a practicaly new XXk for a good price and it will allow me to conduct my own A/B cs Class D experiment. I'm going to power my sub of the 2100XXk (AA assassin) and compare it to my Hifonics 600x1 Zeuse. Z yes the class A/B has less power but I won't be using full power from the 600x1 either! (best I can do is set them with test tones using DMM at under their RMS power (probably 300 watts) the Hifonics SHOULD have a slight advantage here.

I know it's not a controleld lab test blah blah blah but I have no bias at this point so I will only be checking to see if I can tell a difference. If I find the Class A/B amp is much better for SQ then thats what I'm going to get, if I find the oppoiste or no difference then I will be looking for a 1500XXK to match (or maybe I'l get teh alpine). For the price I got the XXK at I figured it won't bother me if my amps are not the same brand //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I decided I'm a bit to skeptical for the class D/T amp to drive my components (DLS Iridiums) with the same SQ as the class A/B. Technicaly it is not impossible but alot has to be done with the signal to get them up to par at higher frequencies if my memory serves me right. I don't have 100's to throw around and I wanted a better/larger amp for my comps anyways (currently have an OLD eclipse 75x2) so I went ahead and got the 2100XXK.

 

[///M5 10+ year member]

In the process have someone adjust the gains incorrectly so that one outputs a db or so more than the other. Don't have the blind tester let you know when they are doing it and I guarantee everytime you will just pick the louder one. Human nature. It makes doing this test really hard and unless you have copious time and processing capabilities I would say well beyond the scope of a DMM.

 

[supa_c 5,000+ posts]

Just get an exhaust that's illegal in California //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Not possible

 

[Justintoxicated 10+ year member]

In the process have someone adjust the gains incorrectly so that one outputs a db or so more than the other. Don't have the blind tester let you know when they are doing it and I guarantee everytime you will just pick the louder one. Human nature. It makes doing this test really hard and unless you have copious time and processing capabilities I would say well beyond the scope of a DMM.

Well I'll adjust the gains to 300 watts with DMM. If anything the hifonics class D will have the upper hand because it has more possible power. if I can't tell the difference then I'll be happy because the 1500XXK fits under my seat while the 2500 XXK does not... Thats the best I can do and it will NOT be a blind test. I have no reason to fool myself, if i can't tell the difference then I will go with the class D

 

[supa_c 5,000+ posts]

The alpines will fit in your glove box //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

 

[htownplaya456 10+ year member]

i have the 2500xxk and i like it a lot... i think it sounds a lot cleaner than most peoples class d but i think its probly mostly its puttin out 1100 watts at 4 ohms... ive had it wired at 2ohms 4 ohms and 8 ohms and personally the 8 ohms sounds the best putting out about 500 watts or so... good choice on gettin the xxk

 

[supa_c 5,000+ posts]

8ohms, probably closer to 300w bridged.

 

[htownplaya456 10+ year member]

well i put it on the meter and after the math was done... it was actually at 524 watts bridged at 8 ohms

 

[JimJ 5,000+ posts]

With no impedance rise? I want your box //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[BMW Sidewayz 10+ year member]

as long as you stick with a quality build and designed amp brand you should be fine when it comes to the sound quality of the class D amp todays technology is to the point that even the low end brand are putting out amps that dont start distorting till a certain point in power. so im sure you dont have to spend $1K on a sub woofer amp to get a decent amplifier. like stated before there wont be an audible difference when comparing the THD of a class d and a class A/B amp as long as your comparing quality amps. the class A/B most of the time will be bigger then the class A amp that produces the same power. the class A/B will be less efficient, produce more heat and be bigger, but will sound just as good. Class D for subwoofer duty and class A/B for midbass and up.

Does that mean I wasted my $$$ on the JL 1000/1 wich is a class A/B?//content.invisioncic.com/y282845/emoticons/mad.gif.c18f003ab0ef8a0d9c27ca78d77a6392.gif

I might sell it then I get the 5Channel Memphis Belle!//content.invisioncic.com/y282845/emoticons/ponder.gif.ec2527b23f1d287b60dcbba54f95edba.gif

 

[BMW Sidewayz 10+ year member]

They have adequate-enough damping.
That's all that matters.

Though on a side note.....some people really enjoy their tube amps primarily due to their lack of damping //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

What is Damping??????//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

 

[PowerNaudio 10+ year member]

Does that mean I wasted my $$$ on the JL 1000/1 wich is a class A/B?//content.invisioncic.com/y282845/emoticons/mad.gif.c18f003ab0ef8a0d9c27ca78d77a6392.gif

why would you say that. i have had a 500/1 amp in the past and the sound quality and build was superv.

if youre asking if you could of spent your cash on a cheaper amp and gotten an amp that would perform similarly to the JL 1000/1, for a bit less amount of cash, posibly!.

the 1000/1 build quality is top notch, that amp should last you a life time if treated well, and operated within the manufaturers recomendation.

an amp is not just an amp. there are allot of things involved in the design of an amp that makes one amp better then the next amp, not just the amp class, but the power supply technology, the sound prosessing technology, the power ampplification stage, componet quality, use of space, the assembly prosess, materials used, etc.... that lowers or raises the price of the amp.

there is more to an amp that meets the eye.

JL amps are very well engineered and built.

you got a great amp that will funtion properly and provide you with quality audio.

lower efiency doesnt mean that the sound quality will be a lower one, class a amps have one of the best sound Quality. but run hot and have the lowest power in to power out ratio in the market. efficiency is very low on them. but are still great amps.

 

[squeak9798 5,000+ posts]

Does that mean I wasted my $$$ on the JL 1000/1 wich is a class A/B?//content.invisioncic.com/y282845/emoticons/mad.gif.c18f003ab0ef8a0d9c27ca78d77a6392.gifI might sell it then I get the 5Channel Memphis Belle!//content.invisioncic.com/y282845/emoticons/ponder.gif.ec2527b23f1d287b60dcbba54f95edba.gif

The JL 1000/1 isn't a class A/B.

It's a class D.

If the salesman told you it was a class A/B.....he was lying through his teeth or severely confused.

 

[thch 10+ year member]

What is Damping??????//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

damping factor. it is a ratio of the impedance of the load to the impedance from the amp. tap a woofer cone not connected to anything. short out the terminals and tap the cone again. notice a difference? damping factor is sometimes refered to as how well the amp can control the speaker, but such is only a good discription when comparing at least one amp with damping factor less that 10. once damping factor starts getting high, the woofer limits the damping of any oscillations.

tube amps often matched output impedance to woofer impedance, for a damping factor of 1. class D amps are a wide range of amplifiers. often, the feedback cannot be sensed after the output filter, thus the resistance of the output filter's inductor is seen in series with the woofer.

 

[BMW Sidewayz 10+ year member]

The JL 1000/1 isn't a class A/B.
It's a class D.

If the salesman told you it was a class A/B.....he was lying through his teeth or severely confused.

You're right, my mistake. I veryfied it on JL site.//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

POWER N AUDIO:

Thats explains why I see some subs moving to vocals and sometimes nothing!! Thanks DUDETTE!!!

THats Why I love Tis Place!!!!!! Thanks Guys!!!!