Mouser is fine, they are an authorized distributor.
Hi wg_ski,
You know, I've owned and worked on many high power amplifiers over the years. I had a Carver Lightstar (series 1), A TFM-75 and use a Marantz 300DC. Worked on stupid amps like a CJ Premier One (250 wpc tube amp) and many high power amps. Carver PM 2.0 were interesting, of course the PM and M 1.5 amps. Very few high power amps sound good (Bryston 4B cubed is a great sounding amp).
Higher supply voltages force some design changes that may negatively impact performance. Some are device types, others would include your voltage amp stage.
At the end of the day you don't really need that much power. 250 wpc is plenty for just about anything at home, a lot less if you are electronically crossed over. My current main speakers are only about 86 dB/watt efficient at 4 ohms. My 300DC can bottom the woofers, but the Marantz 500 and Bryston 4B cubed drive them better. Yeah, I like it real loud! So, what is the solution? More efficient speakers! I'd very much like to grab a pair of Klipsch RF-7 MKIII at 99 dB/watt. I have other Klipsch premier series and really like them a lot.
Efficiency buys you something else. Much lower voice coil temperatures. That keeps the woofers tuned to the box, and you don't lose that much efficiency either. All huge pluses. You might want to rethink that dream system.
-Chris
Hi wg_ski,
You know, I've owned and worked on many high power amplifiers over the years. I had a Carver Lightstar (series 1), A TFM-75 and use a Marantz 300DC. Worked on stupid amps like a CJ Premier One (250 wpc tube amp) and many high power amps. Carver PM 2.0 were interesting, of course the PM and M 1.5 amps. Very few high power amps sound good (Bryston 4B cubed is a great sounding amp).
Higher supply voltages force some design changes that may negatively impact performance. Some are device types, others would include your voltage amp stage.
At the end of the day you don't really need that much power. 250 wpc is plenty for just about anything at home, a lot less if you are electronically crossed over. My current main speakers are only about 86 dB/watt efficient at 4 ohms. My 300DC can bottom the woofers, but the Marantz 500 and Bryston 4B cubed drive them better. Yeah, I like it real loud! So, what is the solution? More efficient speakers! I'd very much like to grab a pair of Klipsch RF-7 MKIII at 99 dB/watt. I have other Klipsch premier series and really like them a lot.
Efficiency buys you something else. Much lower voice coil temperatures. That keeps the woofers tuned to the box, and you don't lose that much efficiency either. All huge pluses. You might want to rethink that dream system.
-Chris
40% efficient isn’t enough for the subwoofers? The big monsters are for the PA. Since one cannot BUY amplifiers like that anymore, and if they could they’d be ten thousand dollars. Those speakers are all horn. I may not be in the business anymore, but I still build the stuff. Some people build stuff to play in the living room, much of the stuff I build is to be played outdoors. Will I get back to it one day? Who knows. But it will be after I don't have a job anymore, that’s for sure. My home audio systems are a bit more sane. Biggest is dual 15 3-ways (Kappa15 LFs) and 200 watt tube amps.
My 101 db 1w1m SP2-XT, I had to wear earplugs to test max power out of my dynaco ST120 . One pair output transistors, 70 v single supply, originally high voltage selected 2n3055 (40636) but I couldn't buy those so I'm using NTE 60 (same soa as MJ15003). 24.2 VAC on speaker for 5 seconds on Rhianna Shut Up & Drive. That volume would drive me out of the room. I listen at 1/8 watt all day to the FM station, 20 watt peaks, which didn't heat them up. The Peavey SP2-XT were stolen, replacement 98 db 1w1m SP2(2004) aren't much of a change. Upgrading amp to a M-2600 which needs no fan to not blow O.T.s, this is my dream system. The orchestra sound is better than the MeyerSound system at Brown Theater where the Louisville Ballet performs.
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lol!
Outdoors! Okay, you're excused and I understand completely! I would love to have the property and system for outdoors fun (that you can feel!). Yeah, 40% is more than excellent!
200 watt tube amps inside? Better you than me. I design and play with tube amps. But my preferred system is SS. Mind you, I modified everything and it sounds much nicer (measures much better too). I found with tube amps that one pair of output tubes is usually the best. Much less for a retube as well. The drawing board has an 80 wpc KT-88 amp on it. That is a lot! The 35 wpc amp does drive my main speakers okay, just not to party levels. I like party levels. Every morning my house feels like a disco, sounds great too as I'm nowhere near clipping. I have three systems tied together for that fun.
Outdoors! Okay, you're excused and I understand completely! I would love to have the property and system for outdoors fun (that you can feel!). Yeah, 40% is more than excellent!
200 watt tube amps inside? Better you than me. I design and play with tube amps. But my preferred system is SS. Mind you, I modified everything and it sounds much nicer (measures much better too). I found with tube amps that one pair of output tubes is usually the best. Much less for a retube as well. The drawing board has an 80 wpc KT-88 amp on it. That is a lot! The 35 wpc amp does drive my main speakers okay, just not to party levels. I like party levels. Every morning my house feels like a disco, sounds great too as I'm nowhere near clipping. I have three systems tied together for that fun.
I use dummy loads to test high power. I'm running 120 wpc into my 98 dB/watt speakers in the bedroom. 
Much cleaner than the ST120 (fixed many). THe 300 DC probably delivers 240 wpc + into the 4 ohm PSB Stratus Gold speakers. They bottom very, very occasionally. I think I went beyond xmax - wouldn't you say?
Anyway, the RF-7 MKIII (99 dB/watt) is probably the last upgrade for my system. That will be stupid loud, and no. I wouldn't leave the room.
Much cleaner than the ST120 (fixed many). THe 300 DC probably delivers 240 wpc + into the 4 ohm PSB Stratus Gold speakers. They bottom very, very occasionally. I think I went beyond xmax - wouldn't you say?Anyway, the RF-7 MKIII (99 dB/watt) is probably the last upgrade for my system. That will be stupid loud, and no. I wouldn't leave the room.
My St120 has the djoffe crossover distortion mod. http://www.diyaudio.com/forums/solid-state/156627-dynaco-stereo-120-can-beautiful.html Also 2 mhz NTE60 O.T. have better high freq I.M. distortion than original 400 khz 2n3055. I can't tell a difference in sound at 1/8-20 wpc from my CS800s which is specified at .003% HD. Good hi-freq from ST120 requires original 2n5320/22 drivers (one surviving pair), or replacment MJE15028/29. TIP31c/32c fairchild drivers were dull & lifeless. Main thing wrong with my ST120 is the fans required to keep the O.T.s from blowing up.I'm running 120 wpc into my 98 dB/watt speakers in the bedroom.
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Well, you need the metal tab to collect and transfer the heat from the die into whatever heat radiating system they come up with. For higher power, you absolutely do need that metal tab. The case is composite and they have the metal down to a minimum. I guess they'll have to come up with another way of transferring heat from the die to the air before they can lose the metal part.
I wasn't allowed to buy from Newark Hamilton Avnet Pioneer etc in 1985. Digikey was still a surplus house as far as I knew. I had the little green flyer. I was not a business. No tax # no invoicing allowed. Plus there was the long distance call required to find out how much freight charge to add to the check. I had to use the TV parts store. With the NTE60 being really white box MJ15003, there was nothing wrong with them. Sound is great. Not to say NTE60 are as good today. The NTE48/49 I bought in 1985 were ****, a leg broke off after year installed.
At an earlier time I worked in an electronics parts supply business. They sold ECG and I was forced to use them. Plenty of failures which I was blamed for. First, I started to poke the leads through the bag and test the parts before using them, that helped a little. Then I started to order real parts (I got hell), but my return rate dropped to near zero. I bought from a place called Electrosonic in Toronto, then from Active Components in Montreal. We started to stock and sell real parts from Active. Once I went out on my own, say 1983 or so, I began ordering from Digikey. Never a problem. I also used to buy parts from a supplier who actually travelled to Japan to buy his stock. I only ever had one or two failures in over 20 years with real parts.
About NTE. You never knew what the real part was as they used a few numbers for each of their numbers. Forget matching them as well. ECG was worse, but they used the same (book of lies) cross reference manual labelled NTE. Complete with intentional errors ECG put in theirs. From measurements, I can tell you these were not first rate parts as the parameters were all over the place. The old RCA parts were good, but again you never knew what the source part actually was. All of this was aimed at the TV repair industry, not the audio market. TV repair folks were typically poorly educated in parts, and things like matching and even bias current! A very lax industry was TV repair in general. I will have to say I knew some excellent, well educated TV repair professionals.
Anyway, NTE / ECG parts are not reliable on average compared to the real parts. The only worse ones are re-marks, now found on Ebay mostly. Ali sells a lot of "new manufacture", but those are fakes by definition. One thing for certain, you cannot trust any part unless it comes direct from an authorized distributor.
My name goes on everything I design, certify, test or repair. I will not risk my name on parts aI can't be sure are the real thing. It's bad enough that real parts occasionally fail, and the design you're working on may not be done well. Why ask for trouble?
About NTE. You never knew what the real part was as they used a few numbers for each of their numbers. Forget matching them as well. ECG was worse, but they used the same (book of lies) cross reference manual labelled NTE. Complete with intentional errors ECG put in theirs. From measurements, I can tell you these were not first rate parts as the parameters were all over the place. The old RCA parts were good, but again you never knew what the source part actually was. All of this was aimed at the TV repair industry, not the audio market. TV repair folks were typically poorly educated in parts, and things like matching and even bias current! A very lax industry was TV repair in general. I will have to say I knew some excellent, well educated TV repair professionals.
Anyway, NTE / ECG parts are not reliable on average compared to the real parts. The only worse ones are re-marks, now found on Ebay mostly. Ali sells a lot of "new manufacture", but those are fakes by definition. One thing for certain, you cannot trust any part unless it comes direct from an authorized distributor.
My name goes on everything I design, certify, test or repair. I will not risk my name on parts aI can't be sure are the real thing. It's bad enough that real parts occasionally fail, and the design you're working on may not be done well. Why ask for trouble?
I could any real part I wanted at Seiscom Delta, Philco Ford, or GE Appliance: for installation in the production equipment. I did manage to get the Pioneer & Hamilton Avnet salesmen to take a check and bring me some parts for my home projects. No shipping charge. But shipping to my home, furgettaboutit. Newark had no saleman that I saw, had the deepest inventory but I couldn't buy from them at home. Until debit cards were invented and they started allowing individuals.
Until webforums were invented I wasn't much good at linear circuits. I had the GE transistor manual 6 th edition that was still promoting transformer coupled power amps. I had another transistor manual bought at the bookstore that delved deep into h parameter theory, whoopie! Then there were the radio shack project books that I soon figured out were full of ****. RS parts wouldn't even last a year, except vacuum tubes. The first time I repaired the ST120 it was putting out 6 watts/ channel. I couldn't figure if the PC15 regulator used a npn or pnp pass transistor, and the modern transistor I installed was clamping rail current at 2 amps for both channels. Too much gain, compared to the dynaco selected original. I didn't get the schematic of the ST120 until I got on diyaudio.com forum in 2011. Found out the regulator circuit was supposed to pass 6.75 amps. My vacuum tube repairs worked much better than solid state until 2011.
I did some amazing systems in TTL & wirewrap at work, but that was just mathematics bought in little plastic packages. Wirewrap on a forest of gold pins, that wasn't a skill that translated economically to home projects. Those gold wirewrap boards were scrapped out about 5 minutes after the microprocessor became the thing.
Until webforums were invented I wasn't much good at linear circuits. I had the GE transistor manual 6 th edition that was still promoting transformer coupled power amps. I had another transistor manual bought at the bookstore that delved deep into h parameter theory, whoopie! Then there were the radio shack project books that I soon figured out were full of ****. RS parts wouldn't even last a year, except vacuum tubes. The first time I repaired the ST120 it was putting out 6 watts/ channel. I couldn't figure if the PC15 regulator used a npn or pnp pass transistor, and the modern transistor I installed was clamping rail current at 2 amps for both channels. Too much gain, compared to the dynaco selected original. I didn't get the schematic of the ST120 until I got on diyaudio.com forum in 2011. Found out the regulator circuit was supposed to pass 6.75 amps. My vacuum tube repairs worked much better than solid state until 2011.
I did some amazing systems in TTL & wirewrap at work, but that was just mathematics bought in little plastic packages. Wirewrap on a forest of gold pins, that wasn't a skill that translated economically to home projects. Those gold wirewrap boards were scrapped out about 5 minutes after the microprocessor became the thing.
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Then along came MCM electronics, with the toll free # and COD. Game changer. Then when McGee gives up the ghost, Parts Express comes in to fill the void.
I was lucky. I was a business later, and became familiar with suppliers working for others and they got to know me. Starting out on my own was easy as pie.
Having a tax number and business number was a magic ticket - as well as a store front. I had no idea these suppliers would not deal with non-businesses until much later.
Having a tax number and business number was a magic ticket - as well as a store front. I had no idea these suppliers would not deal with non-businesses until much later.
First I heard of MCM was when Newark shipped me a TV antenna from there. After they bought them. Where were MCM advertising? QRL? I wasn't a ham radio guy, missed a lot I guess. Blahblahblahblahblahblahblah I had a friend whose father was a ham and the whole schtick turned me off. I got better music from skywave AM radio than all those mythical shortwave radio stations overseas put together.