Advice on Amplifier

Hulk

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I'd like to hook up speakers and sub to my computer. I just bought Onix Rocket Tyke speakers and sub. They are old but I own AV123 speakers and they are awesome. Anyways, on the Onix Rockets I can't find any info on how many watts the speakers are, anyone know? I know that the sub is 100 watts. What kind of small amp should I get for this setup?

Here is a link to the speakers (I have the 2.1 setup not the 5.1 setup).

https://www.digitaltrends.com/speaker-reviews/onix-rocket-tykes-5-1-review/

I'd like to get a small amp and don't really want a AV amp because they are too big, although I guess I could buy one if someone could tell me what small cheap AV amp I could get.

I was thinking about this:

https://www.amazon.com/dp/B077Z7DBR...olid=1SYDWH66RTUXX&psc=1&ref_=lv_ov_lig_dp_it

But it's only 20 watts RMS per channel, not sure how many watts the Rockets are but I'm guessing maybe 50?

What do you guys think?
 
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Cheap amp equals poor sound at elevated volume. Go to https://www.parts-express.com and look. Will investigate and post some solutions for you later for under 200 USD.

Hope this helps I am a retired professional chemist with a specialty in analytical instrumentation and my uncle has a recording studio so I have knowledge of the consumer and pro side of audio.

Do not get to caught up in the specs or being a "measurebator" audio is very subjective and personal.

Must listen to speakers and base on personal taste, all are voiced differently.
Receivers/Amplifiers
The quality of the watt is crucial, for example a discrete Darlington hand wired transistor amp can run over 10K whereas your MosFET receivers are sub $500 (99% of gear bought today). I have a Yamaha DSP receiver, 7 ch which is MoSFET.


The power rating is irrelevant most sound systems play sound best when at under 5 watts continuous give or take. Efficiency rating will tell you how loud a speaker plays at 1 m away with one watt in. My Infinity speakers are rated at 98 dB/watt.
So

1 watt is 98 dB SPL OSHA states no more than 90 dB @ 8 hrs at this threshold without hearing protection
2 watts is 101 dB
4 watts 104 dB
8 watts 107 dB Need to spend ton of money to experience clean uncompressed music at this level or above.
16 watts 110 dB
32 watts 113 dB
64 watts 116 dB
128 watts 119 dB Permanent loss of hearing

Why is this important let say speaker brand X is rated at 80 dB/watt, what power is needed to match my setup?

1 watt 80
2 watts 83
4 86
8 89
16 92
32 95
64 98
128 101
256 104
512 107
1024 110 to get this I need to invest in a Krell, Mark Levinson mono-block in excess of $5000 usd. These high end amps are rated at 1 horsepower which is around 750 W at 8 ohms, 1500 W at 4 ohms continuous), No FET stages, discrete class A.
2048 113
4096 116

Sound output is logarithmic not linear, double power not twice as loud.
For example I am a metal fan, the sound system for Iron Maiden is approx 300 KW at 117 dB this projects thousands of feet. If I do not add speakers or change drivers if I double power to 600 KW it is only 3 dB louder.
 
What inputs do you need for signal and at what budget? Without knowing that, I agree with Drutman, parts-express search for what you need.

Could also look into powered mixers.... depending on what inputs you need. Monoprice is another possible source.
 
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Usually it's better to have more amplifier power than the speakers are rated for to prevent clipping. But honestly, for computer speakers you're fine with almost anything. Looking at your speakers' 2.5" drivers, you're probably looking at low efficiency (~83 db/1w) and a low power handling, probably about 15 watts. At 1 watt per speaker, that's 83+6db = 89 db, which is about the same as a lawn mower. Imagine how loud a lawn mower 3 feet from your head is. That's only 1 watt. You'll be fine with anything in the 10-20 watt range, except tube amps which clip differently. A tube amp could get by with probably 5-10 watts.
 
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Problem is you are assuming flat 20 to 20 kHz freq response. If your curve is -20 dB at lets say 30 Hz for argument, copious amounts of power is required to reproduce it at life like levels.

Assume 1 watt in is 80 db out, so 30 Hz is at 60 dB output at 1 meter.

Output volume (dB) Power input
63 2 W in
66
69 8 W in
72
75 32 W in
78
81 128 W
84 256
87 512
90 1024 These amps are 10 thousand dollar range, Mark Levinson, Krell, Meridian Digital ETC.
93 2048
96 4096
99 8192 W needed to play at symphonic classical / rock concert levels.
 
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Still your missing the point, we do not have the freq curve for the speaker it could drop off a cliff at 100 Hz.
I had access to a high end Velodyne sub when you inputted a 20 Hz tone all you heard/felt was a sharp pain in your ear and a pressure on your chest. With lesser gear you felt/perceived nothing due to the drop off or the driver not being able to reproduce it at any SPL.
 
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I don't think the OP is looking for THX levels from 20-20KHz. Based on other 2.5" drivers like in the OPs speakers, we get a 3db roll off between 125 and 250 Hz. I would assume that crossover and cabinet design would adjust that. Room size/design is also a huge factor, but I'm assuming this is nearfield. And his sub is only an 8" 100w unit, so 100db @ 20Hz was probably out of the question anyway.
Based on looking at a cross-section of 2.5" drivers, 15-20 watts seems to be about the max RMS power rating. Nearfield probably less is needed. That was the OPs question.
 
Over and out on thread, I always enjoy these discussions.
I would recommend a sub 500 receiver to run his system, stay away from the eBay stuff you get what you pay for.
One step away from a fire hazard.
 
so 100db @ 20Hz was probably out of the question anyway.

Yep, probably ~98db at Fs for a lot of those sealed 8" subs at 100w.

drutman How much power does a

1500 W at 4 ohms continuous...... No FET stages, discrete class A.

amplifier pull from the wall during high transient load? Say a sin wave hitting close to Xmax for your woofers? Worst case scenario, to be fair.

I've got a pair of 12's and a 13.5 (3.6ohms total) driven from a class D amp, and that can't pull more than 450w. Can't imagine those with an A topology.
 
Yep, probably ~98db at Fs for a lot of those sealed 8" subs at 100w.

drutman How much power does a



amplifier pull from the wall during high transient load? Say a sin wave hitting close to Xmax for your woofers? Worst case scenario, to be fair.

I've got a pair of 12's and a 13.5 (3.6ohms total) driven from a class D amp, and that can't pull more than 450w. Can't imagine those with an A topology.

Exactly 1500w. That's what class A means, constant power draw regardless of load. What isn't used for sound gets turned into heat. Also known as a space heater. It also is the maximum load for a standard 15 amp wall outlet. And only gives 3db more headroom than a 150w amp.
 
Yep we used to run dedicated lines to high end gear to avoid breaker tripping. Funny with class D amps coming of maturity the true class A amps are becoming the dinosaur of Hi-FI. Hand matching and wiring Discrete Darlington transistors is a lost art.
 
I would start trolling aliexpress for a tpa3255 based amp. Lot of bang for not many bucks.
 
Yep we used to run dedicated lines to high end gear to avoid breaker tripping. Funny with class D amps coming of maturity the true class A amps are becoming the dinosaur of Hi-FI. Hand matching and wiring Discrete Darlington transistors is a lost art.

Them newfangled transistors? Bah. My current project uses 6GV8 / ECL85 / 6F5P tubes. OK, it uses several transisitors/MOSFETs as well, but they're hidden in the chassis. Only about 10-15 watts, but honestly that's more than enough.

I would start trolling aliexpress for a tpa3255 based amp. Lot of bang for not many bucks.

TPA3116 aren't too bad either. That's what I recommend for anyone looking for a quick 10-20 watts.
 
I remember the tube testers at the pharmacies in Maryland. Tubes are come back in guitar amps strong, even order distortion harmonics are easier on the ears.
 
I run cheap and cheerful fx audio tube preamp with GE 5654W tubes (6j1) into a 3255 amp. It sounds mighty good to my ears
 
I'd like to get a small amp and don't really want a AV amp because they are too big, although I guess I could buy one if someone could tell me what small cheap AV amp I could get.

depends on what you call "small" ... the following is 17" (L) x 21" (D) x 8" (H)

used Yamaha RX-V463 on eBay

here's an example of a RX-V463 for sale right now with original Yamaha remote and manual for $114 (shipped). Seller says "Items shipped are packed in a manner equal to or superior in comparison to the efforts of major shippers."

that's important since the first 463 I bought and received last week was damaged in shipping and I'm still waiting for a refund :(

https://www.ebay.com/itm/Yamaha-Natural-Sound-RX-V463-5-1-Channel-105-Watt-Rec-HDMI-Cinema-DSP/402247037077?epid=65638156&hash=item5da7cab095:g:e-MAAOSwhIReqAeP&LH_BIN=1
 
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If you want a decent amp with a lot of power, look for professional amplifiers such as Behringer. They're extremely cost effective and good sounding for the price. 99% of audiophiles cannot reliably tell a pro amp apart from a high-end amp in a blind test. And that's only natural because the music was produced using the pro gear in the first place.
 
I would start trolling aliexpress for a tpa3255 based amp. Lot of bang for not many bucks.
One has to be careful with those China amps. They can have surprising design flaws. See JohnAudioTech Youtube channel, he tests dozens of them.
 
If you want a decent amp with a lot of power, look for professional amplifiers such as Behringer. They're extremely cost effective and good sounding for the price. 99% of audiophiles cannot reliably tell a pro amp apart from a high-end amp in a blind test. And that's only natural because the music was produced using the pro gear in the first place.
I've had very good results with Crown power amps, too. The XLS 2502 is a beast.
 
I'm currently renovating my scratch-to-purpose built listening room. 6 inch double walls with damping, back to back quadratic diffusers, multi-channel, electrostatic main channels etc. All in a separate utility building of course.
And I'd be happy to be able to plug in one of the three subs sitting in a closet right now -- currently, the 6.5" Klipsch towers put out enough bass to be objectionable in this paper-walled place. The Atmos array is sitting in another box...
 
And I'd be happy to be able to plug in one of the three subs sitting in a closet right now -- currently, the 6.5" Klipsch towers put out enough bass to be objectionable in this paper-walled place. The Atmos array is sitting in another box...
This is the wiring setup of my hobby room (speaker cables, aux 240V output for listening spot and lighting). Note that the room is acoustically much larger at low frequencies including side walls which helps with standing waves, bass frequencies partially penetrate the side wall and almost completely disregard the back wall... The side walls have 6 inch deep acoustic dampening with barriers (velocity based dampening and layered mass loaded surfaces, then a 2 inch air gap to the actual outer wall of the building.

Näyttökuva 2020-5-8 kello 4.18.12.png
 
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