I’m going to be bringing home some JBL 4315s soon and was considering building a NP FW to drive them. Any recommendations? I have built the ACA but want more juice for this project. I think I’d like at least 50 watts per channel, maybe even up to 100, is this f5 territory?
89 db/ 2.83V
8 Ohms
Almost any of them.
You won't need 100W unless you play music at disco levels
8 Ohms
Almost any of them.
You won't need 100W unless you play music at disco levels
Pico, aren't you supposed to be sleeping now? 😴😴😴
Nobody calls it a disco anymore but I'm old enough to know what a disco is and also old enough to not know what it's called now (club? rave? music festival?) 😉
Donna Summer - I Feel Love 1977 (High Quality) - YouTube
Nobody calls it a disco anymore but I'm old enough to know what a disco is and also old enough to not know what it's called now (club? rave? music festival?) 😉
Donna Summer - I Feel Love 1977 (High Quality) - YouTube
Yes, but extra headroom is nice, and I think better for whatever speaker you drive with it. And, demos r fun!
Yes but then that starts limiting the amps you can build because you've placed an unnecessary requirement on your decision process.
I bet you would have extra headroom with even 10 W. People use far less power than they think.
I bet you would have extra headroom with even 10 W. People use far less power than they think.
Yes, I mostly agree, however I have run other speakers w similar efficiency on my ACA and they would all benefit from more power. If you have another suggestion I’m happy to research it. I know a lot of you guys have already been there and done that...
My main listening rig is Altec 605a’s run by a 40wpc tube amp.
My main listening rig is Altec 605a’s run by a 40wpc tube amp.
There is no doubt that most people will run out of power when using ACA and listening at loud volumes.
Most people don’t listen at loud volumes continuously, normal listening is quieter than most people think, and so ACA is reasonable for 90% (or more) of the time.
Anyway, all the 25w class-A amps (F4 F5 F6 Aleph J M2x etc...) sound significantly and unquestionably bigger and louder than even a pair of bridged ACAs. Any of them will be the ‘more power’ you are looking for. The space and effort required for 3 or 6 dB more power past that (I.E., 50 or 100wpc) is notable and things get very large very quickly.
...which can be a lot of fun. 🙂
Read the F5T article, see what’s interesting. I’d also look for information on the Aleph J, M2x and F6.
Most people don’t listen at loud volumes continuously, normal listening is quieter than most people think, and so ACA is reasonable for 90% (or more) of the time.
Anyway, all the 25w class-A amps (F4 F5 F6 Aleph J M2x etc...) sound significantly and unquestionably bigger and louder than even a pair of bridged ACAs. Any of them will be the ‘more power’ you are looking for. The space and effort required for 3 or 6 dB more power past that (I.E., 50 or 100wpc) is notable and things get very large very quickly.
...which can be a lot of fun. 🙂
Read the F5T article, see what’s interesting. I’d also look for information on the Aleph J, M2x and F6.
I ran an M2x on a pair of some old NHT towers (i think 86 or 88db cant remember) and it was loud. More than enough to **** off the neighbors but i vote to monoblock some F4s. Nice Swiss Army knife to have on the shelf
To keep your power options you will first want to buy the 4U x 500mm chassis.
Get in on the group buy before they run out.
You can build a monster amp with it.
Yeah, for building a higher power amp, the OP can do far worse than
to take advantage of this unique opportunity.
How much Power?
I don't think I really listen at excessive levels. Yet, I was surprised to see clipping lights come on quite often on my 60 wpc Japanese amp. (An Akai) back in the 1980s. Clipping finally blew the tweeters on my Infinity 8 Kappa towers. I upgraded at that time to an Adcom GFA-555 II. I seldom (but not never) saw the clipping lights come on on that amplifier.
Basically, the question is not what is your average listening level. It is what is you maximum listening level. If you want realistic sound levels, it is amazing how quickly you run out of power. A 90 dB @ 1W, 1m speaker will be about 80 dB SPL at your listening position (say 3m away from the speakers). Add 3 dB for stereo. That means you need 100W to get 103 dB SPL at your listening position.
You amplifier needs to have enough power to satisfy the loudest, peak SPL you ever expect to reproduce, not your average listening level, in order to save your tweeters. If you listen to music with a large peak-average power ratio (PAPR), then you need more power, even if your average listening level is modest.
While average db SPL levels of classical performances are usually below 90 dB, peaks can be as high as 120 dB for highly dynamic performances. (In the audience--on stage can be much louder.) ALL RECORDINGS AND BROADCASTS ARE COMPRESSED, so this dynamic range at home is impossible. You likely will only need to reach peaks of about 105 dB at your listening position. This corresponds to a 150 W/ch amplifier to reproduce. If your speaker is more sensitive than 90 dB SPL @ 1W, 1m, then adjust your power down by 50% for each 3 dB. and up by 100% for each 3 dB below 90 dB SPL sensitivity.
Please follow OSHA limits to protect your hearing. 90 dB is OK for 8 hours. 100 dB is OK for 2 hours. I personally don't like to listen to music loud for that long. Now I want a dB meter.
WHAT ARE REALISTIC VOLUME LEVELS?
I don't think I really listen at excessive levels. Yet, I was surprised to see clipping lights come on quite often on my 60 wpc Japanese amp. (An Akai) back in the 1980s. Clipping finally blew the tweeters on my Infinity 8 Kappa towers. I upgraded at that time to an Adcom GFA-555 II. I seldom (but not never) saw the clipping lights come on on that amplifier.
Basically, the question is not what is your average listening level. It is what is you maximum listening level. If you want realistic sound levels, it is amazing how quickly you run out of power. A 90 dB @ 1W, 1m speaker will be about 80 dB SPL at your listening position (say 3m away from the speakers). Add 3 dB for stereo. That means you need 100W to get 103 dB SPL at your listening position.
You amplifier needs to have enough power to satisfy the loudest, peak SPL you ever expect to reproduce, not your average listening level, in order to save your tweeters. If you listen to music with a large peak-average power ratio (PAPR), then you need more power, even if your average listening level is modest.
While average db SPL levels of classical performances are usually below 90 dB, peaks can be as high as 120 dB for highly dynamic performances. (In the audience--on stage can be much louder.) ALL RECORDINGS AND BROADCASTS ARE COMPRESSED, so this dynamic range at home is impossible. You likely will only need to reach peaks of about 105 dB at your listening position. This corresponds to a 150 W/ch amplifier to reproduce. If your speaker is more sensitive than 90 dB SPL @ 1W, 1m, then adjust your power down by 50% for each 3 dB. and up by 100% for each 3 dB below 90 dB SPL sensitivity.
Please follow OSHA limits to protect your hearing. 90 dB is OK for 8 hours. 100 dB is OK for 2 hours. I personally don't like to listen to music loud for that long. Now I want a dB meter.
WHAT ARE REALISTIC VOLUME LEVELS?
I don't use more than 0.5 Watts on dynamic peaks with 98dB speakers
That would be 2W for 92dB speakers
So about 4W for 89dB speakers
To avoid clipping lets call it 10W, so a 25W amp should be more than enough for home use without the police knocking on your door.
Anyway nothing wrong with building a 100W amp but it's a shame not to consider the 25W Firstwatt amps as they are all excellent and more than adequate for home use.
That would be 2W for 92dB speakers
So about 4W for 89dB speakers
To avoid clipping lets call it 10W, so a 25W amp should be more than enough for home use without the police knocking on your door.
Anyway nothing wrong with building a 100W amp but it's a shame not to consider the 25W Firstwatt amps as they are all excellent and more than adequate for home use.
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