The listing on the back of various models indicates that your model 900, is rated at 450 per channel at 4 ohms. It also looks like the amp has circuitry for constant voltage for use in a sound distribution system, ie, 70 voltage output for distribution loudspeakers.
Shall is a mandate. Shall is used in engineering design for engineers who have to specify equipment. My Father is a professional engineer, retired, and sometimes had to spec sound equipment. A professional licensed engineer is legally responsible for the design of whatever they are working on. So, if something is spec'd as having a specific power output, then it has to have that power output. It's not like consumer gear where they say, "it has 100 watts - ish," and they can get away with it. If the item is professional, and spec'd for a PA system, as designed by a licensed engineer, then the amp must perform. If the engineer gets sued because the amp doesn't do what it is specified to do, then the engineer sues the amplifier manufacturer.
FWIW, Crest made a V series and also a Vs series. I think the data on the back is probably used for both, thus the "V/Vs" text. I suspect that amplifiers like this lost their value when reliable Class D amplifiers came along. Class D amplifiers have more power, less weight.
Is transistor hfe (gain) matching pair is used in audio amplifier.? How much it's important? Should we have to use same hfe value transistor? Your kind response will help me lot.
I have 3 of the bigger bros to this one the 1500. V is metered, Vs isn't, otherwise identical. These were a lower price Crest install series, I really like mine and yes the fans are a little loud but mounted in a rack not too terrible. The bigger ones have a toroid and are even heavier.
Pretty much all homes in the US have 240 volts at their disposable. For some reason people in other countries think we run on 110 volts which is also wrong. 120/120 (240) split phase power is what's in most homes in the US.
I get your point, but I just can't run 100ft of cable from apartment's kitchen to my room. No problem in some ones basement, you can do pretty much whenever is possible.
No 240 outlet? Grab 120 from one circuit and 120 from another on the second 180 degree leg. Crude, but it works. Lol. I’ve done it myself also in a pinch for running a small welder where there was no 240 outlet.
Yeah, John should get some cash out of those repaired units, sold them to other people, and get components for your own, seem out of capacitors or what.
You SHALL list that amplifier and SHALL make some pocket $$.
List that amp in the boating section under large anchors.
Thanks for showing us Snickers. I always look forward to seeing him.
What a beast. Find it a new home & put some cash in your pocket
Strsight onto eBay and go buy that distortion analyser !
Might rattlecan the case first thought.
Love the VU meters.
Your videos are a real pleasure to watch
Bob Cordell designed this for Crest. Source: he told me. :)
Snickers seems tired but still doing well.
This is what I'm into, power amps!
Well that's one powerful amplifier right there.
I love that clip cord 240VAC arrangement. But with my electrician hat on, that is a fire, shock and explosion hazard.
The "shall" nomenclature is the design specification. This is common on pro gear documentation. Look at the specs on JBL pro drivers.
Yep, "shalls" and "shoulds" are differentiated in engineering speak.
From the specs, it seems like it should be able to run from 120V. Is it just a transformer tap?
Nice found! Thanks for vid.
The listing on the back of various models indicates that your model 900, is rated at 450 per channel at 4 ohms. It also looks like the amp has circuitry for constant voltage for use in a sound distribution system, ie, 70 voltage output for distribution loudspeakers.
Shall is a mandate. Shall is used in engineering design for engineers who have to specify equipment. My Father is a professional engineer, retired, and sometimes had to spec sound equipment. A professional licensed engineer is legally responsible for the design of whatever they are working on. So, if something is spec'd as having a specific power output, then it has to have that power output. It's not like consumer gear where they say, "it has 100 watts - ish," and they can get away with it. If the item is professional, and spec'd for a PA system, as designed by a licensed engineer, then the amp must perform. If the engineer gets sued because the amp doesn't do what it is specified to do, then the engineer sues the amplifier manufacturer.
@@Willam_J Indeed. This term is used in mechanical engineering by the likes of BAE, Rolls-Royce, et al.
Oops ! Sorry, the amp didn't have 70 voltage distribution system output! My mistake! Lol 😆
So the amplifier ain't dead
The rumors of its demise have been greatly exaggerated.
The amp shall blast polka music!
🤢🤢
Crest is another really good Power amp. I would have checked the Power transformer to make sure its not possible to run it on 110Vac ....
FWIW, Crest made a V series and also a Vs series. I think the data on the back is probably used for both, thus the "V/Vs" text.
I suspect that amplifiers like this lost their value when reliable Class D amplifiers came along. Class D amplifiers have more power, less weight.
I replaced a bunch of 80 pound amplifiers with amps that weigh 8 pounds that have better specs and cost less.
i shall give you a thumbs up.
Thou "Shall" Have a Excellent operational Crest Amp MANG..!
Is transistor hfe (gain) matching pair is used in audio amplifier.? How much it's important? Should we have to use same hfe value transistor?
Your kind response will help me lot.
For lowest distortion, matching is recommended. It is not critical for operation.
I have 3 of the bigger bros to this one the 1500. V is metered, Vs isn't, otherwise identical. These were a lower price Crest install series, I really like mine and yes the fans are a little loud but mounted in a rack not too terrible. The bigger ones have a toroid and are even heavier.
Nice looking amp, you had a great result there ! its basically new with zero dust inside, see if you can make a little money on it....cheers.
I worry that it hasn't been used. Capacitors that haven't seen plate voltage lose their oxide coating. But it seems to have survived power on.
Nice video
Pretty much all homes in the US have 240 volts at their disposable. For some reason people in other countries think we run on 110 volts which is also wrong. 120/120 (240) split phase power is what's in most homes in the US.
I get your point, but I just can't run 100ft of cable from apartment's kitchen to my room. No problem in some ones basement, you can do pretty much whenever is possible.
@@pliedtka Think you might have commented under the wrong post?
Are you planning to give it away to one of your European viewers?
No 240 outlet? Grab 120 from one circuit and 120 from another on the second 180 degree leg. Crude, but it works. Lol. I’ve done it myself also in a pinch for running a small welder where there was no 240 outlet.
If you don't need that amp, you could reverse the polarity on the fan and have a small air-conditioner!
3:21 That's engineering speak; take a look at the US ASME specification if you really want it laid on thick.
VS is the model # You have the 900
Lucky you. For home use you will never need the noisy fan. It's not like you're pouding 200W+ all the time.
Yeah, John should get some cash out of those repaired units, sold them to other people, and get components for your own, seem out of capacitors or what.
Don't sell it too cheap! Cosmetic repair effort worthwhile.
They'll probably sit in a pile until I have time to sell them.
so... it was fine... they probaliy wired to 120 lol.. OMG
Crest=Peavey......Same $hit....different name....Peavey bought Crest like 20yrs ago.....
Looks like junk
You don’t know what you’re looking at.