Just wondering if anyone here has tried this with low efficiency speakers. I have a pair of 6ft tall magnepan planar speakers that i restored that are very inefficient but people say that having huge power is the key to get the best out of them some people have audio amps with 500w rms per channel (megabucks) and being on a budget far below that pa seemed like a good idea-are there any amp brands that are particualarly good with resolution, detail etc?
I've done it. My last PA amp on a Hi-Fi rig was a Crest 700 WPC beast that I dialed back to 150 watts. I was I'd had that for the power hungry Magnepans. There are good and bad PA amps, and yes many of them have noisy fans that are never heard over concert level PA but that would bother you at home.
You want something fully old school and without fans if possible.. though there are a few exceptions that will work. You probably don't need kilowatts of power, a true 250w/ch will totally outclass any box store AVR that can be bought these days. So my suggestions would be to look for a classic (80's to '90s) pro power amp from one of the major manufacturers, these were big heavy beasts(50lbs +) but if you have never owned something like this the amount of clean headroom available will astound you.
One of the exceptions with fans you could use are the Yamaha P-s series, these were some of the last conventional amps build before everything went class D. They are a hybrid design that utilize a class AB amplifier but with a highly efficient signal tracking power supply, and the result is very little waste heat is generated so even though there are fans they almost never turn on. I own 5 of these now... every model except the P2500s which might be big enough for your application. I believe these are out of production so you may only find one used but it will still have lots of life left in it, and prices on these are quite reasonable... I have picked up some of the larger models over the last couple years for only $350.
https://www.diyaudio.com/community/threads/quiet-pa-amps.339848/
Yamaha P-series has gone up in price in the UK substantially over the past 1.5 years. If your looking for a more modern amp the IMG Stageline STA-2000D has Pascal modules (high quality class D).
It appears the 2000 is a 4 channel that can bridge. While the 1000 is 2 channels that can bridge. The 1000 is little over half the price at £320+
https://monacor.co.uk/sta-1000d.html
Edit: 275 https://www.ebay.co.uk/itm/134099693706
I did once blow my hifi speakers up with a PA amp. Maplins mosfet kit, two of the 150s bridged for 400w, twice. Hours before the party, the protection board wouldn't have it. So I pushed the relay across, and saw actual light come from one of my tweeters.
What is the minimum impedance of the Magnepans? That is important to consider before trying an amp bridged.
Cheers!
Cheers!
FWIW, I keep a Crown MA5002VZ around for these occasions. Macrotechs and other old-iron amps, if they've been properly looked-after, can sound excellent. The MA5002VZ has variable-rate fans so you don't really notice them in a domestic setting, but IIRC the smaller ones are just on full-power all the time.
QSC RMX would also be worth a look - just fit a silent fan.
Chris
QSC RMX would also be worth a look - just fit a silent fan.
Chris
Most MA5000/5002 are in poor health in 2022. The ones I have worked on have solder joints to the power transistors going bad, PCB track failures, small signal resistor failures and other age/thermal cycling issues. They are very complicated and hard to fix due to the weird mechanical construction and use of floating power supplies and live heatsinks.
I haven't personally heard one, but I've read many good things about BGW amps. Supposedly Paul Klipsch had a preference for them back in the day
My older P, not P-S, series Yamaha amps are fan cooled but I've never had the fans come on at home. Just because it has a fan doesn't mean it sucks - like a vacuum cleaner.
I've been using pro audio amps, mostly, for a very long time.
Spotted a BGW250D on ebay. Downloaded schematic from electrotanya. That LM318 op amp is really dated. 100 nv/sqrthz ? A 5532 is 10. At least my Peavey amps use NJM4580 at the input.
Has anyone tried to re-compensate one of the old BGWs for a 5532 op amp? I know the general topology can be made to work with one - just wondering if someone had gone ahead and stuck one in there in place of a dead 318 and figured out what cap changes were needed with their circuit.
I was using a Yorkville AP1200 on my Energy RC70 speakers... I now using it in bridged mode to drive a 15" sub.
Early haflers are highly recommended, only the very large 500/600 had fans. They didn’t seem to bother most home users, many people with hungry or difficult speakers use these. Today they could be replaced with nearly silent computer fans. The P series were also factory made (not kits). Idk about later haflers, seems like the quality was called into question and home use went down.
I know a lot of home hi-fi using crown amps to power subs. I have not used current crown amps but my crown 300a ran in my home setup for 10 years and then another 20 on the bench testing everything I built or bought. No fan, no hiccups, no load issues, lots of power. A unit today would likely need some level of refresh which would not be cheap (the oil can PS caps are 100$+ these days)
I know a lot of home hi-fi using crown amps to power subs. I have not used current crown amps but my crown 300a ran in my home setup for 10 years and then another 20 on the bench testing everything I built or bought. No fan, no hiccups, no load issues, lots of power. A unit today would likely need some level of refresh which would not be cheap (the oil can PS caps are 100$+ these days)
I think there was a reasonably-priced Yorkville fanless studio amp (SR300?), and I've read favourable things about a Behringer amp, the A500.
I've used a Peavey PV8.5C to run subwoofers; the fan was essentially silent except during some action movies or in very hot weather. I can't comment on its sonic characteristics, but you can look for it on the internet. Music stores and pawn shops may have those amps used.
Of amps I've owned, I'd suggest the NAD 2200, which has oodles of headroom, and despite being broken when I acquired it, was able to fix. Not so much the Carver M1.0t, which was temperamental then stopped working altogether.
I've used a Peavey PV8.5C to run subwoofers; the fan was essentially silent except during some action movies or in very hot weather. I can't comment on its sonic characteristics, but you can look for it on the internet. Music stores and pawn shops may have those amps used.
Of amps I've owned, I'd suggest the NAD 2200, which has oodles of headroom, and despite being broken when I acquired it, was able to fix. Not so much the Carver M1.0t, which was temperamental then stopped working altogether.
I've been happy with Peavey PV-4c I repaired for $40(blown) +parts $80 (120 w/ch 8 ohms) and CS800s (bad Power Supply) for $100+$40 parts (240 w/ch 8 ohms). The burglar was so happy with them he carried them off to his fence in 2018. I since used a mono MMA-875T with 2 mixer cards $50 with freight (75 watts) until I scored a stereo MA-2600 for $120 + $30 new capacitors (70 w/ch 8 ohms). Fans on PV-4c & CS800s are not loud at room levels of power (1/8 to 50 W). MA-2600 has no fan. My music room speakers are SP2(2004) with 98 db 1w1m. MMA-875t is now amplifying 30" HDTV through a TOSLINK converter to $5 (Salvation Army) speaker in the TV room. Mixed in headphone output of PC running firefox.
PA amp that will be donated to a church is a QSC CX302 $110 working. Fan is really too loud for home use. Church uses 20 W average, so CX302 under a table away from podium shouldn't be audible.
PA amp that will be donated to a church is a QSC CX302 $110 working. Fan is really too loud for home use. Church uses 20 W average, so CX302 under a table away from podium shouldn't be audible.
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I don’t know about that A500. It’s not exactly a PA amp (a little small for that) and needs some mods in the front end to make it minimally acceptable. Those Carver cubes aren’t exactly stellar either. Build quality sucks and when they get temperamental sometimes it’s game over. I had a friend who had one and actually liked it, but never played it loud. The the triac went out and took the funky transformer with it. I rebuilt the exact same audio circuit, put in a conventional power supply at a rail voltage between the low and mid rails, and he never looked back. Turns out 50 watts was enough.
My latest amp used in the home audio rig was the Yamaha P3500. The only problem was my wife accidentally blowing tweeter ribbons all the time. It’s too much power for compressed commercials coming on at 0 dB. This happens when the remote controls get in a funk. I need to look into something smaller for that system, as the “loud” system now uses more indestructible speakers, 200 watt tube amps and lives in the shop.
My latest amp used in the home audio rig was the Yamaha P3500. The only problem was my wife accidentally blowing tweeter ribbons all the time. It’s too much power for compressed commercials coming on at 0 dB. This happens when the remote controls get in a funk. I need to look into something smaller for that system, as the “loud” system now uses more indestructible speakers, 200 watt tube amps and lives in the shop.
Did the title of this thread change - or did I never notice how bad it is?