I have thoroughly enjoyed Dave Rat university this past year.

This is a really good topic. I can add one thing they may help clarify the issue. There's no standard that manufacturers have to use to measure an amps power. Each manufacturer does it their own way. That's why you can go to Walmart and get a 1000 watt home theater in a box for $99. The reality is, if you took 5 amps all rated for the same power, like 100 watts into 8 ohms, every one will measure differently if you did them all the same way. Its been a problem in the industry for years.

Also immensely grateful for Dave Rat University. Thanks for the heads-up about the notifs!

Finally! Glad you shared a version for the public.

I was conversing with a soundman friend about this very topic today - most timely, Dave! We talked about how the digital guitar processor, recorded into software, processed by plugins, played back through a digital mixer into digital amps is "removing the heavy cream, then the light cream, then the 4% milkfat, then 2%, and we're left with nonfat milk" in sound reproduction. I just missed an auction for a Crown MacroTech 5002 Anniversary Edition with a copper faceplate that sold for $1700. Crown only made 200 of them. Of course, then I'd need to buy some passive JBL's (again) to go with it. We're looking forward to this series, Dave, thank you very much for your great dives into our beloved passion.

So true, I used to demo for people a 30 Watt per channel stereo amplifier and showed it put out more clean sound than a cheaper 250 Watt amplifier. The the 30 Watt amplifier was rated into 4 ohms both channels driven at less than 0.1% THD. Clean 60 Watts RMS in a store is quite loud. The 250 watt amp on the other hand was listed a total peak power with no mention of distortion level. On an oxcilioscope, the 30 watt amp put out a little over twice the voltage non-clipped than the 250 Watt amp, or 6DB more clean power out of the speaker. RMS watts specified into a restive load and at a specified distortion level and sine wave is the way to compare apples to apples. In the repair shop, used to torture test amplifiers by running them at their rated power into a dummy load. Not all amps survived. Those that did were stocked. Those that failed to perform to spec were returned. An amp that will do peak un-distorted power for 15 minutes is a good amp. The numbers that interested me most are not published. How many volts peak to peak does the amp clip into 8 ohms, 4 ohms, 2 ohms, and one ohm if applicable. Can it sustain the peak value for a long time? I used to measure this. Double the voltage = twice the voltage at twice the current into a fixed load or 6 DB more power.EG a 50 volt signal is 6 DB less than a 100 Volt signal. This is the difference between a 100 Watt amp and a 400 Watt amp.

Love your videos Dave. Thank you for everything you do and God bless.

I’m so glad I found this video. I’ve been putting my old stereo system back in play but and so far I’ve back off a couple amps because I don’t want to blow my speakers or mess up my system. I definitely need 1000 watts even if I need new speakers lets go😂

Hey Dave it's great your going to have a deep dive into this topic, what makes it more interesting is how there are similar issues and confusion with regard to how the loudspeakers are dealing with the power fed to them, I'm guessing that we will learn quite a bit about that too along the way. Think I'm gonna need some popcorn ; )

Dave, really love learning from you - and thanks for the sub test at the end of the video, that was awesome!

Thanks for sharing your experience Dave.

I definitely wanna see the powersoft results. But this sounds like an awsome test. Cant wait for these next few videos!

I didn't know Einstein had a brother? Dave is Great. Watched all videos ! Learned a LOT !!!

Dave rat is an American hero, specializing in audio. A paramount definition of mad scientist. Cant get enough of this guy, I would watch an 8 hour video of him exploring something as bland as e-tape vs gaff tape because he would make it fascinating, he should really start his own school, it would bankrupt fullsail and ultimately exponentially progress the industry via its graduates

Great stuff, Dave. I will make you smile. Back in the early 80's.... Hill DX700 running 2 ohm per channel into 4 Gauss 4560's and 4 JBL K120 . Incredible amp. 😊😊

Thank you so much Dave! Love your videos. So pragmatic and yet so warm, they are really inspiring! Learned A LOT just by watching them!

One other thing that changed is Slew rates, I've been updating the IC's in my Urei 527's to modern IC's for faster slew rates. In terms of those older amps with big heavy transformers versus the modern stuff with lightweight torodials I never considered how long they could put out RMS very awesome video as always!

I'm a bit of a sucker for Crest Audio amps, So I'm extremely intrigued as to what the results are. I've had a lot of experience with their CA series and have always been pleased with the results, especially when driving subs.

Ultimate master SENSEI thanks for all of your time you have taken to make these videos. Super appreciated

Glad to see these topics brought up. Pat Brown and has worked a lot to develop a standard way of evaluating amplifiers and speaker ratings. See Common Amplifier Format (CAF). Then you have the rabbit hole of loudspeaker 'power' ratings. In reality the term 'power' is not the best term. In reality we care about how much voltage an amplifier can deliver and over what time frame (yes totally on board with the limitation of many modern designs to deliver full voltage for less than a second); and for many uses that is fine. But sometimes you need an amp that delivers full power for a second or two. Also getting people to understand that with most music (or voice) the real power draw on an amp is going to be at 1/4 to 1/3 the stated power rating is a challenge (when in use at at full volume). Good info. You have worked through this in the trenches.

Your content is fantastic.

Thank you so much for sharing your knowledge, Dave! Much love from Russia.

Would love to see an old EV P series amp tested, P3000/CP3000.

Dave muchas gracias por compartir tu conocimiento y experiencia, saludos

So excited to watch the next episode…thanks for sharing Mr. Rat.

I guess the question also is, if you do one amp for the whole frequency spectrum versus splitting spectrum. Love to see more on this!

Thank you 👍 I am using old EV P3000’s can’t say they are easy to lift, But I enjoy the headroom

Love this content. The breakdowns and examples are super helpful for a layman trying to learn.

What a cool dude you are , always a fresh look at things that really matter Cheers

Look forward to the amp test!!!

This will be super interesting!

Very interesting, as always with your videos.

Must be 30 years ago, Sound on Sound did a amp test under real world conditions feeding speakers and with resistors, tapped off the amp's output, fed it up the hall to a second room, and into a small reference amp and speakers. Then listened to the reference system only. This allowed them to match gain between amps, and keep the reference listening level constant with the test amp at 1W or 200W. They must have A/B compared to the source as well. I look forward to hearing your discoveries.

As always, very informative and thought provoking video. Thanks for taking the time out of your busy schedule to further educate us on live sound.

I would be interested to see how an LA12X performs in this test

Hi Dave , Im from Panama in central america , I learned a lot with your videos , thanks for share your knowledge.

Finally!!! A objective amp test!!

Great video Brother Dave, you are a badass!

It would be great to see the power delivery duration between a Powersoft X4 & a Lab.Gruppen PLM12K44!! Looking forward to more of these videos Dave.

I have an early 70’s Acoustic bass amp that’s “only “ 300 ish watts 😎 it’ll flap your trousers at 5 meters away through Ampeg cab and the amp almost vibrates itself off the top 👍🏻 I’ve also got a Bugera Nuke that’s supposed to be powerful and there is no comparison, the old amp blows it away completely:-) and it has more character 👍🏻

I’ve been really curious about this topic lately. I picked up a QSC gx5 and a pair of crown k2s this summer which are both rated at 500 watts per channel at an 8ohm load. I’m using the gx5 primarily for my Yamaha club s115 tops and one crown k2 for a pair EAW jf260 tops and the other in bridge mono for EAW two sb180 subs in parallel. I’ve been wondering what the main difference is between these new and old amps are and look forward to continuing this journey with you!

Thanks for the video. Recently I bought an old amp at auction to fool around with and i was wondering if you could help shed some light on it. Its about 18 years old and made in Australia by a now-defunct company called MSR. There's no manual and details about it are slim. What I do know is on the back it reads "This amplifier produces 850W RMS into 4ohms per channel continuously, 1600WRMS bursts." And on the inside, instead of a handful of large capacitors it has about 30 small ones per channel. If you don't mind, I've got two questions; a) what kind of mutant am I dealing with? and b) could you recommend an appropriate sub driver for small parties? Cheers

Will be brilliant, can't wait 🙂

Nice shirt, If you are from the area you know that place. I love their business signs and that they change it weekly.

This series should be good.

The size of the voltage rails and how much and how quickly they can swing is very important. The “new” QSC amps have large voltage rails and their FAST power supply technology that does some cool things including the ability to parallel amplifier channels not just bridge them.

oohhh watt is this video going to be about I wonder!

I had to take out the IEC power connectors and hardwired cords of the proper guage into all my amplifiers. I haven't had an amplifier failure since then. The IEC power connectors are THE number one cause of amplifier failures as they are only meant to carry 10 amps. The 20 amp IEC only carries 15 amps. The power lights don't dim on my amplifiers any more. If you don't believe me, put a volt meter between one of the lines and the corresponding connector in the amplifier and drive it at full power - 20 to 30 volt difference and drop between wall receptacle and power switch inside the amplifier!. I have 3 dozen Cerwin Vega CV-5000 amplifiers rated for 5,000 watts each. They came with 20 amp IEC's - i could not get the amplifiers to put out anything past 2,925 watts bridged at 4 ohms. When I hardwired 8 guage power cords into each of them - 6,600 watts bridged at 4 ohms, pulling 60 amps peak each amplifier.

Would you typically recommend using the amplifier the manufacturer recommends from their own brand before researching an amp that may be more dynamic and clear like you’re describing?

Bought a few cheap pcb amps recently. As a 90's child it was almost commical seeing a 300w rated amp..(thats actually 20 watts constant, if that in reality)

Very interesting...I know I am being totally subjective, but I like my older amp sounds using almost any speakers more than the newer models. They try to make speakers that react more efficiently to the "new' class D amps, and maybe they are successful...I have no clue, because I am just a listener and not very knowledgeable about the technicalities.

I don’t know if it’s related to your view counts dropping, but the join option for your channel is missing on all of my iOS devices. Shows fine on Android. I wouldn’t think this would cause notification issues tbh, but good luck notifying peeps about their lack of notifications with more notifications.

There is a specification that is often overlooked and that’s the power supply. In my opinion, the majority of amp specifications come from the abilities of the power supply. As you go from an A, A/B, etc amp, the power supplies are different. I’ve used a lot of Crown Macro Tech amps in my day and the power switching capabilities of these amps are quite astounding in my opinion. Also consider my usage of small live gigs for around 500 people. My old Marantz 2250 home stereo with 75 watts/ch blows the doors off my newer NAD stereo that said to be 150 watts/ch. a quick look inside and you’ll find completely different power supplies. Another issue is the quality of your electrical service. Under high demand are you still getting the power required to produce the amps specified power ratings…….??

Oh Dave... Please help are you familiar with turbosound tsw-218 boxes? The guy I bought them from PAINTED THE WIRING ONE SOLID COLOR .. Any good way to test polarity on each side of the box? Maybe a dumb question.. 🤷

I'm also interested in the amount of AC current the amp draws vs watts it puts out. Is it a linear relationship or not at all?

Hey Dave. So I got an amp question for ya. I have a pair of Danley full range passive boxes rated 4 ohm. Boxes are rated 1k cont, 4k peak. I have the choice of powering them with either a Chevin A6000 or a QSC Powerlite 6.0II. Both amps are comparable in power obviously the Chevin has better distortion specs. I’m leaning Chevin, but what do you think?

I'd be curious to hear your thoughts on Meyer's M Noise as a test signal for measuring system headroom? The idea being that the crest factor of the signal more closely resembles typical program material while providing a standardised test signal.

1:50 he’s on it for one and all !

Ideally specced modern amp also distorts differently, and faster. It is more gradual slope in old amps once you do go over the limits whereas modern amp will go to high distortion very soon. 120W continuous from a 100W modern amp can sound absolutely awful, where with old tech you don't notice anything yet but you can measure it. The price to pay for that is inefficiency, it will draw more power all the time. If the specs are true and properly measured they are real limits these days, when in the past it was more or less a guideline. I've used 1.5x rating in the past, but it should probably be 2x now (have two times more power in the amps than you need)

Please man this is something i have always wondered cause a few months ago i learned that a Graphics card in a pc running max fan speeds at all times to stay cool let's it boost all the time meaning i get up to 20fps more in gaming titles when underload and ever since then i have wondered if the same can carry over to amps cause in the end equipment runs better when cool but ofcourse there is many variables as you stated but the point stays this is why i like amps with a better damping factor cause it gives me an indicator on wether it will hold power for longer and better or not but this is not a fool proof way of choosing an amp.

Love your videos Dave, would be interested for you to explain the nitty gritty of speaker impedance and the fact it's not constant (changes with frequency) as this plays heavily into the topic of amplifier power capability, power transferred from amp to speaker is very much dependant on the impedance of the load.

Hi Dave . I have an old Carvin HT760M 750 watt amplifier . I I think I had for years and wanted to use with a Behringer Xenyx 802 for small gigs. But it sounds like crap . I tested the cables and mixer all good the amp seems like the issue . It has buttons on the back Parallel / Limiter / Ground /Lift and a recessed one for bridge . Any advice to dial it in ? Thanks

Watched on my uhd curved samsung TV. 1st video played no problems then it wouldn't play others after.

I’m just waiting until you launch Rat University then I’m enrolling.

First time on your channel and I like your approach on this subject but I heard no mention of the most important thing when it comes to audio amplifiers and that's their "REAL" purpose, amplification in dB. For me it's more of an important topic than raw power that an amp can handle. Example: It's much more realistic to say a 60w amp has around 20dB amplification capability,that tells you it's potential to amplify sound. With a proper setup you can make a 100w amp play louder than 1000w amp with a bad setup < low sensitivity speakers, bad cables etc.> I know watts are important and easier to understand but that's why they're more misleading. If you haven't touched this subject there's an idea for another video...

Great video. 😀👍♥️

Crown DC-300A is my king ;)

the 'how quickly it can deliver the power' is slew rate, am i correct? Volts per fraction of a second. Its specced for just about every piece of amplifier silicon but i dont think ive ever seen it specced for a power amp system. In terms of the sustained power handling it would be really cool to monitor the B+/- lines of the power supply, just at the transient caps would probably be ideal, for how quickly supply collapses when its hit with large loads, this (effectively the power supply impedance vs capacitance) will be what determines a lot of the power collapse, and often noise on a prolonged large signal i believe. Wish i could join ur paid crew but being a disabled pensioner i am really trying not to enable youtube payment or patreon etc cos i feel like it will be a bottomless pit i cant afford, but i appreciate your content. ty

9:08 this doesn't sound right to me, surely if you are putting it down to 2 ohms thats MORE load, not 'half' (Putting two 4 ohm speakers in parallel gives 2 ohms) therefore it can use more of its potentially available power, like saying driving a tractor up a big hill rather than on the flat. it might then be able to use all its horsepower. I agree with everything else you say btw.

BEEN WAITING< AWSOME

Hi have you tried kv2 audio speakers/amps? I wonder what your thoghts on them

@Dave Rat, Should we buy all the FP6400 there are? Before your video gets out and price will sky rocket?

I`m still a die-hard fan of the BGW 750B`s and Phase Linear 700`s of the `70s. While their power ratings pale in comparison to modern class D amplifiers, the torque the old linear power supply amps deliver just cant be matched by some of the modern amps whose power ratings are many times higher.

I miss My old crest amps. I don’t miss the weight of the racks which is why I changed them out for modern amps - but I still swear the crest’s had a better dynamic range and just overall better sounding….

Thanks Dave, I will love to see the powersoft video but before that my question is how doo I know the exact speaker impedance, ohms an wattage is this are not written on the speakers or with wrong information?

Thanks Dave. I was told that you would need ten times the power to double the volume. Is this true? I really like my old A/B International power amps. Clean with tons of headroom.

Any Lab Grupen or Mc2?

seems like when you listen to home audio stuff, a McIntosh amplifer that is rated at 300W per channel is a lot louder and clearer than a Sony or other consumer brand rated at 500W or more..

Please do the behringer inukes

Awesome!!

This will be a good one! So... New Watts vs Old Watts? Or, perhaps; New 𝙍𝙖𝙩𝙚𝙙 Watts vs Old 𝙍𝙖𝙩𝙚𝙙 Watts ??? Pirates; "𝘞𝘦 𝘸𝘢𝘯𝘵 𝘵𝘩𝘦 𝘟 𝘢𝘹𝘪𝘴" So cool you're going to explore down this rabbit hole, far too many liberties are taken with amp output ratings. It'd be cool to see wattage rating profile... via a suite of measurements. Most importantly measurements that incorporate time. Yes, use the X axis instead of simply the Y axis. Hell yeah, the X axis the honesty axis;) Absolutely offer an all out burst rating, but also include what's sustainable over brief, musically significant periods. Then of course a torturous long term rating which essentially is a throughput capability (not just caps providing for bursts), from the circuit breaker all the way to the load. Also, down this rabbit hole path perhaps some myths can be addressed. Far too much mythology in that "No amplifier can output more than 2400w"... (120v 20a). However breakers can pass massive amounts of current past their rating. To avoid nuisance tripping, a 20a circuit can pass 7-8 times the rated 20a trip amount, that's for about a second or a bit more. It'll pass up to 3x for up to 10sec or so. Amazingly the 20a circuit, can allow up to 1.5x-2x the rated amount for as long as 30 seconds. 100amps for around 1-2 secs 60amps for around 10 secs 30-40amps for up to 30 secs These numbers a big time impactful to high power amplifiers in both pro audio rigs, and HQ home hifi, studio/mastering systems, etc. Implications? Upsize your feeds, avoid voltage drop choke-points. In other words; Build the church for Easter Sunday.

I have a pair of old early 90s peavey amps, cs800x & cs1000x pushing a small bag end speaker system for my synths/euro stuff. I love them but my rolling mixer rack weighs as much as an elephant😂 anyone have any budget friendly recommendations on a lighter pair of amps? Subs are 800w and tops are 600w...

Back in 80 s in the UK you had to cheapo audio system s that would claim instantaneous peak per channel summed at 10% THD. Then came NAD Watts. A very different thing.

The complete spec should be: X - Watts at 8 ohms 20 to 20k at less than .5% Total Harmonic Distortion. Without all those specs it's tough to compare! RMS!!

Have you look into cvr amps compared to the powersoft

Ganahl Lumber rocks

Crown 5000 Vz

❤️❤️❤️

If anybody is going to find new and interesting ways it’s you.

Like a light bulb. Calling it a 60 watt light build just defines how my power it consumes. You can get the same amount of lumens with a 15 watt LED. Watts are irrelevant until the utility bill comes. And there is a big difference in the decibels from a 100 watt solid state guitar amp and a 100 watt tube amp. I have a 50 watt Marshall tube and that is much louder that my 100 watt Peavey solid state amp.

Only 3 dislikes lol holy sht who can get through this lol sorry Dave but jeezus man!

whats?

Let's not forget THD.