Onkyo TX-SR805 BAD Problems

[LAB3]

I have really enjoyed this Receiver(Great HD decoders) but now this is the second time in last 6 months it has stopped working. Yesterday it just quit playing a CD in the Blu-ray player. So I grabbed the remote and turned it back on.........Crack. and a flash of light from the right rear and a that had a burnt motor smell came out before I could hit the button to turn it off. I unplugged it and the right rear was warmer then the rest of the case. I also have alwways had a fan blowing on it as has always run Much warmer then my old 5 year old Yamaha RX-V2400(no HD decoders) that I had to hook back up to my main system. 6 months ago the front end display went out...resistors went bad...$185.00 to fix warranty was out.(The repair Tech said there was a note from Onkyo about this problem) thanks Onkyo for not telling us befoore the warranty ran out. I plugged it back in and turned it on again, front display came on then another crack and small stream of black smoke, all in about 2 seconds. Turned it off and it sets in the closet. I looked on Ebay and found 4 other 805's for sale...In Parts.WTF Looks like the 805 had so serious design flaws. Looking at a Yamaha RX-V2065 that has the same specs as the 805.....never again on a Onkyo,,all firmware upgrades had to be done ata Onkyo Repair Dealer Only.. anyone else have a problem with a 805???

 

[Seth=L]

It's sad the TX-SR805 had such reliability issues, because it is otherwise an excellent machine for the money. Never before had I seen such an amplifier section in a receiver with a street price of under $1k for new receiver. I believe its greatest strength may attribute to its greatest weakness. The heat the TX-SR805 generates is extraordinary and as we all know, heat is the enemy of electronics.

I am sorry to hear of your receiver woes. I really liked the TX-SR805, too bad it had to be a nightmare in terms of reliability.

 

[fightinkraut]

Sorry to hear about your trouble, I have an 805 and am continually impressed by it, never had an issue. Regarding the resistors on the front panel that is something than can be done with some inexpensive parts from Radioshack and a little soldering knowledge. I've never had to do it personally but have read any others doing it.

Regarding the heat, I bought some fans from http://shop.ebay.com/drmckenzie/m.html?_nkw=&_armrs=1&_from=&_ipg= and it runs pretty cool.

Lastly, firmware updates do not have to be done at a service center, with a RS232-USB adapter you can do them at home, there's a good thread at AVS about that. Not officially supported mind you, like the new AVR's that update via ethernet, but quite doable.

 

[LAB3]

Sorry to hear about your trouble, I have an 805 and am continually impressed by it, never had an issue. Regarding the resistors on the front panel that is something than can be done with some inexpensive parts from Radioshack and a little soldering knowledge. I've never had to do it personally but have read any others doing it.

Regarding the heat, I bought some fans from http://shop.ebay.com/drmckenzie/m.html?_nkw=&_armrs=1&_from=&_ipg= and it runs pretty cool.

Lastly, firmware updates do not have to be done at a service center, with a RS232-USB adapter you can do them at home, there's a good thread at AVS about that. Not officially supported mind you, like the new AVR's that update via ethernet, but quite doable.

Thanks for the fan link..........the fan I use is larger then them, so I know I was venting the Onkyo really good and it had 10" of air space above the unit.
Not stacked in a rack and opened up the back of the cabinet/flat screen stand for better air flow.. This model Onkyo Always ran MUCH hotter then my Yamaha RX-V2400 that has about the same specs. Do a search on Ebay and see how many 805's are for sale. yesterday None that worked
I loved they way the HD decoders worked..bitstreamed audio from Bluray the seperation was awsome. Hope your 805 last longer then 2 1/2 years.

I was not aware that you could upgrade the firmware with a adaptor at home. Oh well it's fried.... don't trust it now to spend money for repairs a second time. Looking for a new HD Yamaha and extended warranty.

 

[jostenmeat]

I would bet good money the only time that the display fails is when the user leaves it on high setting. Which surprises me, because even the low setting is bright to me (which I *still* cover with window tint). The high setting is like crazy blindingly bright, because, well the resistor values are not well chosen.

Here are the pic by pic instructions for replacing the resistors in your display.

805 Display Fix

 

[LAB3]

I would bet good money the only time that the display fails is when the user leaves it on high setting. Which surprises me, because even the low setting is bright to me (which I *still* cover with window tint). The high setting is like crazy blindingly bright, because, well the resistor values are not well chosen.

Here are the pic by pic instructions for replacing the resistors in your display.

805 Display Fix

Wish I would have seen this several months and $185.00 ago. But now there something REALLY bad shorted out now. Loud "Crack" and dark black line of smoke and burt smell if turned on for a second. The display lights up but then "Crack" and burning smell, smoke and it turns off before I can hit the button. back right rear had a flash of light and that corner was even Hotter then normal HOT. It's in a bright room with windows and fan always on it.
Any ideas???? I miss the HD Master on Bluray movies now. Older Yamaha RX-V2400 about same specs but not HD decoder. reason I got this one.

 

[tomtjp]

YEah...me too

I have an 805 too...and loved it till last night the same thing you described happened to me...it sparked...power wavered...smoke came out from the rear....and then shut down...unplugged everything like the manual says for 1 hr..but no luck...shuts down and blinks red...any ideas?

 

[LAB3]

I have an 805 too...and loved it till last night the same thing you described happened to me...it sparked...power wavered...smoke came out from the rear....and then shut down...unplugged everything like the manual says for 1 hr..but no luck...shuts down and blinks red...any ideas?

Sorry, Onkyo said it cost more then it's worth to repair. Buy a new AVR. I found a Yamaha with the same specs as the 805, very happy. But lets see 3 years from now. My 2400 Yamaha is a 2003 model about the same specs but not HD or it would still be in the den, not in bedroom playing TV in there.
Good luck with what ever model or brand you buy, look for a extended warranty, some have 5 years at B&H.

 

[PharmD]

Yeah, stick to Yamaha, Pioneer, Denon, Marantz.

 

[TLS Guy]

I have really enjoyed this Receiver(Great HD decoders) but now this is the second time in last 6 months it has stopped working. Yesterday it just quit playing a CD in the Blu-ray player. So I grabbed the remote and turned it back on.........Crack. and a flash of light from the right rear and a that had a burnt motor smell came out before I could hit the button to turn it off. I unplugged it and the right rear was warmer then the rest of the case. I also have alwways had a fan blowing on it as has always run Much warmer then my old 5 year old Yamaha RX-V2400(no HD decoders) that I had to hook back up to my main system. 6 months ago the front end display went out...resistors went bad...$185.00 to fix warranty was out.(The repair Tech said there was a note from Onkyo about this problem) thanks Onkyo for not telling us befoore the warranty ran out. I plugged it back in and turned it on again, front display came on then another crack and small stream of black smoke, all in about 2 seconds. Turned it off and it sets in the closet. I looked on Ebay and found 4 other 805's for sale...In Parts.WTF Looks like the 805 had so serious design flaws. Looking at a Yamaha RX-V2065 that has the same specs as the 805.....never again on a Onkyo,,all firmware upgrades had to be done ata Onkyo Repair Dealer Only.. anyone else have a problem with a 805???

I think your problem is to quite a large extent your speakers.

I think the problem with that Onkyo, is that they have biased it too far to class A to improve audio quality. Most receivers are biased far too far to class B to be quality units. The problem is in receivers there is only room for puny devices which can't take the heat of biasing further to class A.

The issue is crossover distortion which is hidden in the usual bench tests. Crossover distortion increases as power output decreases! That is why to me receivers sound pretty dreadful and gritty. The more the output devices are biased to class B the greater the crossover distortion and the cooler the devices run. The more they are biased to class A, the less the crossover distortion and the hotter they run. At full class A they run hot all the time, even at idle.

Now your speakers are amp killers.

They use an auto transformer, as the horns have to see constant impedance. However the amp sees anything but. I understand from descriptions on the NET that the impedance of those speakers is below below four ohms a good deal of the time, and phase angles are well in negative territory. This does not surprise me as are a quasi series design. Series crossovers are always tough on amps.

The other issue is that the caps used on those speakers are known for severe deterioration over time which compounds the problem.

Also in your speakers there is huge overlap between the mid and HF horn also compounding the problems.

A redesigned crossover was available, but it no longer is. However you can build the modified crossovers. The auto transformer has to be preserved.

I strongly advise you replace these crossovers before you blow up and more output devices.

Now the modified crossover makes the speakers rated at a four ohm load. They are effectively four ohm or less in any event, however there are some huge impedance peaks, which allowed them to be rated 8 ohms which they are not.

With the lowering of margins on newer receivers, I would strongly recommend an external amp. So get a receiver with pre outs.

Since these speakers almost certainly present unusual amp loading, I would highly recommend a Quad 909 current dumping amp. Peter Walker's designs, were guaranteed stable under all loads.

Also these amps are unique in that the output devices can be biased well towards class B. The output dumpers are corrected by a small very high quality class A amp, in a feed forward arrangement. So you have class A performance without a huge amount of heat. There are six high current output devices per channel. The devices are never stretched and long life can be expected. Performance is determined by the small class A amp. The Quad 909 has no crossover distortion. These amps are of a build quality of your Revox A 77 Mk4. That unit is of a build quality far above the rest of your system.

You other option is to ditch the Klipsch Cornwalls.

I have attached the circuit you can build to update your speakers and make them a safer load.

If you can not build them yourself, I would be prepared to build them for you. I would need your boards, as I would need the auto transformers.

 

[3db]

I think your problem is to quite a large extent your speakers.

I think the problem with that Onkyo, is that they have biased it too far to class A to improve audio quality. Most receivers are biased far too far to class B to be quality units. The problem is in receivers there is only room for puny devices which can't take the heat of biasing further to class A.

The issue is crossover distortion which is hidden in the usual bench tests. Crossover distortion increases as power output decreases! That is why to me receivers sound pretty dreadful and gritty. The more the output devices are biased to class B the greater the crossover distortion and the cooler the devices run. The more they are biased to class A, the less the crossover distortion and the hotter they run. At full class A they run hot all the time, even at idle.

Now your speakers are amp killers.

They use an auto transformer, as the horns have to see constant impedance. However the amp sees anything but. I understand from descriptions on the NET that the impedance of those speakers is below below four ohms a good deal of the time, and phase angles are well in negative territory. This does not surprise me as are a quasi series design. Series crossovers are always tough on amps.

The other issue is that the caps used on those speakers are known for severe deterioration over time which compounds the problem.

Also in your speakers there is huge overlap between the mid and HF horn also compounding the problems.

A redesigned crossover was available, but it no longer is. However you can build the modified crossovers. The auto transformer has to be preserved.

I strongly advise you replace these crossovers before you blow up and more output devices.

Now the modified crossover makes the speakers rated at a four ohm load. They are effectively four ohm or less in any event, however there are some huge impedance peaks, which allowed them to be rated 8 ohms which they are not.

With the lowering of margins on newer receivers, I would strongly recommend an external amp. So get a receiver with pre outs.

Since these speakers almost certainly present unusual amp loading, I would highly recommend a Quad 909 current dumping amp. Peter Walker's designs, were guaranteed stable under all loads.

Also these amps are unique in that the output devices can be biased well towards class B. The output dumpers are corrected by a small very high quality class A amp, in a feed forward arrangement. So you have class A performance without a huge amount of heat. There are six high current output devices per channel. The devices are never stretched and long life can be expected. Performance is determined by the small class A amp. The Quad 909 has no crossover distortion. These amps are of a build quality of your Revox A 77 Mk4. That unit is of a build quality far above the rest of your system.

You other option is to ditch the Klipsch Cornwalls.

I have attached the circuit you can build to update your speakers and make them a safer load.

If you can not build them yourself, I would be prepared to build them for you. I would need your boards, as I would need the auto transformers.

Thats odd. Other than the class D amps, most receivers I thought were class AB rather than class B. In a class AB amp, the only distortion that can be found is cross over distortion like you say as the signal crosses from positive into negative and visa versa. I'm also of the understanding that crossover distortion can be almost but eliminated through careful matching of transistor pairs.

About that graininess that you here... very few power amps in the industry today run fully class A. We both can mention a few brands that truly are class A but they are far and beyond in the minority. Its just not economically viable. Its expensive as hell and is highly inefficient. Most power amps run class A up to a certian power point where they switch into class AB mode. So if power amps don't sound grainy to you, I'm thinking that the graininess is just your bias against receivers.

I apologize for the defensive posture about AVRs but you continoulsy put them down for very poor reasons. When used in conditions that they were designed for like a small to miedium sized room and mid to efficient speakers, an AVR can supply many years of great service.

The problem with Onkyo IHO is that they did not do their homework when it comes to heat dissipation. No other brand discussed in here as seen as many thermal issues as does Onkyo. The OP should move to Denon if he must have Auddseey or he can try out Yamaha with the improved multipoint YPAO with reflection control. Both of these manufacturers have seen very little in the way of thermal issues, almost none. Onkyo really needs to rexamine their design approach with respect to heat issues.

 

[TLS Guy]

Thats odd. Other than the class D amps, most receivers I thought were class AB rather than class B. In a class AB amp, the only distortion that can be found is cross over distortion like you say as the signal crosses from positive into negative and visa versa. I'm also of the understanding that crossover distortion can be almost but eliminated through careful matching of transistor pairs.

About that graininess that you here... very few power amps in the industry today run fully class A. We both can mention a few brands that truly are class A but they are far and beyond in the minority. Its just not economically viable. Its expensive as hell and is highly inefficient. Most power amps run class A up to a certian power point where they switch into class AB mode. So if power amps don't sound grainy to you, I'm thinking that the graininess is just your bias against receivers.

I apologize for the defensive posture about AVRs but you continoulsy put them down for very poor reasons. When used in conditions that they were designed for like a small to miedium sized room and mid to efficient speakers, an AVR can supply many years of great service.

The problem with Onkyo IHO is that they did not do their homework when it comes to heat dissipation. No other brand discussed in here as seen as many thermal issues as does Onkyo. The OP should move to Denon if he must have Auddseey or he can try out Yamaha with the improved multipoint YPAO with reflection control. Both of these manufacturers have seen very little in the way of thermal issues, almost none. Onkyo really needs to rexamine their design approach with respect to heat issues.

When you are used to not having crossover distortion you are very sensitive to it.

Solid state class A amps a just a huge problem. They run hot all the time and have high failure and add up a huge electric bill.

I would bet that Onkyo did bias towards class A more than is usual in receivers and paid the price.

The set point between class A and B in an A/B amp differs widely from design to design.

You never get a perfect transistor match, and I would bet in a consumer product there is no attempt to, as it increases cost hugely.

The other issue is that the component tolerance in the output stage has small room for error also. As components age this also worsens the crossover distortion issue.

That is what is so brilliant about Peter's feed forward amps. You get class A performance with a cool running output stage. No need for fans at all. No need to match power devices. The components can go out of spec around 30% as they age and no affect performance, because of the self correcting nature of the design.

I would bet that if you bought one, you would never go back. I'm certain it is this issue that drives people to tubes more than anything else.

 

[LAB3]

I think your problem is to quite a large extent your speakers.

I think the problem with that Onkyo, is that they have biased it too far to class A to improve audio quality. Most receivers are biased far too far to class B to be quality units. The problem is in receivers there is only room for puny devices which can't take the heat of biasing further to class A.

The issue is crossover distortion which is hidden in the usual bench tests. Crossover distortion increases as power output decreases! That is why to me receivers sound pretty dreadful and gritty. The more the output devices are biased to class B the greater the crossover distortion and the cooler the devices run. The more they are biased to class A, the less the crossover distortion and the hotter they run. At full class A they run hot all the time, even at idle.

Now your speakers are amp killers.

They use an auto transformer, as the horns have to see constant impedance. However the amp sees anything but. I understand from descriptions on the NET that the impedance of those speakers is below below four ohms a good deal of the time, and phase angles are well in negative territory. This does not surprise me as are a quasi series design. Series crossovers are always tough on amps.

The other issue is that the caps used on those speakers are known for severe deterioration over time which compounds the problem.

Also in your speakers there is huge overlap between the mid and HF horn also compounding the problems.

A redesigned crossover was available, but it no longer is. However you can build the modified crossovers. The auto transformer has to be preserved.

I strongly advise you replace these crossovers before you blow up and more output devices.

Now the modified crossover makes the speakers rated at a four ohm load. They are effectively four ohm or less in any event, however there are some huge impedance peaks, which allowed them to be rated 8 ohms which they are not.

With the lowering of margins on newer receivers, I would strongly recommend an external amp. So get a receiver with pre outs.

Since these speakers almost certainly present unusual amp loading, I would highly recommend a Quad 909 current dumping amp. Peter Walker's designs, were guaranteed stable under all loads.

Also these amps are unique in that the output devices can be biased well towards class B. The output dumpers are corrected by a small very high quality class A amp, in a feed forward arrangement. So you have class A performance without a huge amount of heat. There are six high current output devices per channel. The devices are never stretched and long life can be expected. Performance is determined by the small class A amp. The Quad 909 has no crossover distortion. These amps are of a build quality of your Revox A 77 Mk4. That unit is of a build quality far above the rest of your system.

You other option is to ditch the Klipsch Cornwalls.

I have attached the circuit you can build to update your speakers and make them a safer load.

If you can not build them yourself, I would be prepared to build them for you. I would need your boards, as I would need the auto transformers.

I have new networks from Bob Crites(type "B" cross overs) in them. And have had Zero problems with a 2003 Yamaha AVR that still works (no HD). These were my late Fathers Cornwalls as was the Revox.
Thanks for the info on the "Special" amps the 805 have. The 805 burned up HDMI parts and front end display when it was in warranty.......as neither of those two problems have anything to do with my speakers.......Sorry Doc but the 805 had more problems then the amps Bro. The 3RD and last time that the 805 Quit that you are posting about??? I have read other 805 owners had the same thing happen too and they did not own Klipsch Heritage Speakers. Not sure why the same thing (crack and smoke) happened to these non Klipsch owners.You know way more about this then I do.

My new Yamaha RX-V1900 HD 7.1 is built use it as a Pre/Pro. It sounds so good on the AVR amps in this Very small den. Lets see if the new Crites cross overs and the new Yamaha are OK together in the last 32 years we have had Fisher, McIntosh and 1993 Kenwood AVR(still works) and now the 2003 Yamaha AVR was on them until 2007 HD 805, now the HD Yamaha AVR. I will take my chances on the new Yamaha AVR having NON special rated amps and Not burning up parts 3 times. Why did the 1990 Kenwood(5amp) AVR and the 3003 Yamaha 7.1 AVR last for years and they both still work?????

I am a retired Machinist and work on old Corvette's, I know nothing about the networks. PM me on sending you my stock C/O boards as they were still working when I replaced them 2 years ago.(worried about oil filled caps leaking, they were dry) I have looked at ALK networks and for my small room his more expensive Extreem Slope C/O would be wasted in such a small room I have my HT gear in. I do not use 1/2 of the AVR power to play my system 85 DB on Bluray movies. Corns are front L&R. I have found if you want you speakers to sound better use then in a smaller room, unless you have Klipsch Khorns that Need a larger room

I now have two 6" fans blowing on my AVR and opened up the rear of my cabinet and have always had about 6" of top venting space for all my AVR. The 2 fans made a Huge difference. I can watch a Bluray and push the AVR more then normal for just stereo and place my hand on top.....COOL now" so maybe having "Lesser" rated amps in the cheep($1,300.00 retail) Yamaha AVR will last for years like the other 2 AVR have lasted. We spent a lot of money over the years keeping tube seperates running as all I could do was use my Mighty Might tube tester and if tubes were not bad send them in for repair. 80% of my use now is movies(need HD audio and HDMI) I have Verizon FIOS HD TV and hundereds of DVD and Bluray movies. I have limited funds to spend right now on extra amps that when I can afford them I will look at the amps you listed to use with my AVR. Tinman (Marc) has my Revox and he has replaced EVERY Rifa,Franko, the Red Devils, Green one's, motor run caps etc,(about 50 a lot of green and red) several resistors and new heads etc...... Sonic Cleaned all the Boards, cleaned and oiled the 3 motor bearings Isoflex PDP 65 etc, so my extra cash is going into the Revox. But I am interested in these amps you posted about. I will Google them as I have a 5.2 HT system and having 5 external amps would be nice. But right now they are not necessary for the tiny room all my Klipsch speakers are in. The Corns are in corners and towed in,aiming at the center of the sofa 7' back and the Corns are about 8' apart and rear speakers are 7' behind the sofa. Center speaker is just above the 55" inbetween the Corns and 2 Klipsch Sub12" 300/650 Bash in this small room with 8' ceilings. This combo of old and new Klipsch "Sounds" much better in this room then it "Looks" on paper. Thanks For the Info.

Louis

 

[TLS Guy]

I have new networks from Bob Crites(type "B" cross overs) in them. And have had Zero problems with a 2003 Yamaha AVR that still works (no HD). These were my late Fathers Cornwalls as was the Revox.
Thanks for the info on the "Special" amps the 805 have. The 805 burned up HDMI parts and front end display when it was in warranty.......as neither of those two problems have anything to do with my speakers.......Sorry Doc but the 805 had more problems then the amps Bro. The 3RD and last time that the 805 Quit that you are posting about??? I have read other 805 owners had the same thing happen too and they did not own Klipsch Heritage Speakers. Not sure why the same thing (crack and smoke) happened to these non Klipsch owners.You know way more about this then I do.

My new Yamaha RX-V1900 HD 7.1 is built use it as a Pre/Pro. It sounds so good on the AVR amps in this Very small den. Lets see if the new Crites cross overs and the new Yamaha are OK together in the last 32 years we have had Fisher, McIntosh and 1993 Kenwood AVR(still works) and now the 2003 Yamaha AVR was on them until 2007 HD 805, now the HD Yamaha AVR. I will take my chances on the new Yamaha AVR having NON special rated amps and Not burning up parts 3 times. Why did the 1990 Kenwood(5amp) AVR and the 3003 Yamaha 7.1 AVR last for years and they both still work?????

I am a retired Machinist and work on old Corvette's, I know nothing about the networks. PM me on sending you my stock C/O boards as they were still working when I replaced them 2 years ago.(worried about oil filled caps leaking, they were dry) I have looked at ALK networks and for my small room his more expensive Extreem Slope C/O would be wasted in such a small room I have my HT gear in. I do not use 1/2 of the AVR power to play my system 85 DB on Bluray movies. Corns are front L&R.

I now have two 6" fans blowing on my AVR and opened up the rear of my cabinet and have always had about 6" of top venting space for all my AVR. The 2 fans made a Huge difference. I can watch a Bluray and push the AVR more then normal for just stereo and place my hand on top.....COOL now" so maybe having "Lesser" rated amps in the cheep($1,300.00 retail) Yamaha AVR will last for years like the other 2 AVR have lasted. We spent a lot of money over the years keeping tube seperates running as all I could do was use my Mighty Might tube tester and if tubes were not bad send them in for repair. 80% of my use now is movies(need HD audio and HDMI) I have Verizon FIOS HD TV and hundereds of DVD and Bluray movies. I have limited funds to spend right now on extra amps that when I can afford them I will look at the amps you listed to use with my AVR. Tinman (Marc) has my Revox and he has replaced EVERY Rifa,Franko, the Red Devils, Green one's, motor run caps etc,(about 50 a lot of green and red) several resistors and new heads etc...... Sonic Cleaned all the Boards, cleaned and oiled the 3 motor bearings Isoflex PDP 65 etc, so my extra cash is going into the Revox. But I am interested in these amps you posted about. I will Google them as I have a 5.2 HT system and having 5 external amps would be nice. But right now they are not necessary for the tiny room all my Klipsch speakers are in.
Thanks For the Info.

Louis

If you have the Bob Crites crossovers you are good to go.

As you know I'm far from a receiver fan, but Onkyblow are probably close to the bottom of the heap. I have never been impressed with that outfits offerings going way back. So it is a good idea to stay clear of those.

 

[LAB3]

If you have the Bob Crites crossovers you are good to go.

As you know I'm far from a receiver fan, but Onkyblow are probably close to the bottom of the heap. I have never been impressed with that outfits offerings going way back. So it is a good idea to stay clear of those.

I know expensive seperates will have larger amps and more expensive parts in them. I wish you could set in the center of my sofa. You would not have posted sell the Cornwalls. I have had Yamaha receiver amps on my Klipsch Heresey speakers for years before I went AVR. Yamaha amps have always mated good sound wise with Cornrwall and Heresey. I can't say about any of the other Heritage, as I have had several sets of Heresey from back in the early 1970's.
Pop had Khorns in the late 1960's when I was a teenager.WOW they were accurate. But he had Fisher and McIntosh seperates on them.
I played the violin in a orchestra back in Elementary and Jr. High School. So I had "That Sound" as a base for what I thought a speaker system should sound like...too "ME" everyone hears different and every room has it's problems for adjusting a system to sould like "You" like. I read so many posts "Horns" are too bright, Harsh......uhh adjust the Eq and move the speakers around. This cracks me up when I read these posts. And I usually just don't reply as I have never NOT been able to tune my horns so they were NOT harsh or "Out Front" of the rest of the music. SMALL room is the key for a AVR and having 2 fans on them. I sure have had Great results with Yamaha AVR and my speakers in a small room.Time will tell if this model Yamaha HD AVR will last as long as the others, except the Onkyo done with them. Why did my other AVR last for many years and NOT burn up parts on Klipsch speakers????????
Thanks Doc

Louis

 

[3db]

When you are used to not having crossover distortion you are very sensitive to it.

Solid state class A amps a just a huge problem. They run hot all the time and have high failure and add up a huge electric bill.

I would bet that Onkyo did bias towards class A more than is usual in receivers and paid the price.

The set point between class A and B in an A/B amp differs widely from design to design.

You never get a perfect transistor match, and I would bet in a consumer product there is no attempt to, as it increases cost hugely.

The other issue is that the component tolerance in the output stage has small room for error also. As components age this also worsens the crossover distortion issue.

That is what is so brilliant about Peter's feed forward amps. You get class A performance with a cool running output stage. No need for fans at all. No need to match power devices. The components can go out of spec around 30% as they age and no affect performance, because of the self correcting nature of the design.

I would bet that if you bought one, you would never go back. I'm certain it is this issue that drives people to tubes more than anything else.

Tube amps generate alot of even order harmonics which gicves them that warm sound people flock too. Its a personal preference thing and nothing wrong with that.

 

[TLS Guy]

Tube amps generate alot of even order harmonics which gicves them that warm sound people flock too. Its a personal preference thing and nothing wrong with that.

True, but crossover distortion is very unpleasant even in small quantities. It is also highly under recognized, as it is hidden in standard testing. Most tube amps are free of it. The ear will tune out a lot of even harmonic distortion easily and readily, but object violently to small amounts of crossover distortion.

I would bet mid and low end receivers are just loaded up with crossover distortion.

 

[LAB3]

True, but crossover distortion is very unpleasant even in small quantities. It is also highly under recognized, as it is hidden in standard testing. Most tube amps are free of it. The ear will tune out a lot of even harmonic distortion easily and readily, but object violently to small amounts of crossover distortion.

I would bet mid and low end receivers are just loaded up with crossover distortion.

How can I find out if my Yamaha RX-V1900 HD AVR ($1,399.00) retail is loaded up with crossover distortion??

 

[TLS Guy]

How can I find out if my Yamaha RX-V1900 HD AVR ($1,399.00) retail is loaded up with crossover distortion??

It takes patience. You need a good scope and signal generator. You need to look at the trace in the transition zone at a wide number of power levels and loads, especially trying to find the transition power of A to B transition. And you need a distortion analyzer.

 

[LAB3]

It takes patience. You need a good scope and signal generator. You need to look at the trace in the transition zone at a wide number of power levels and loads, especially trying to find the transition power of A to B transition. And you need a distortion analyzer.

Ok......well that is over my head as I do not own a scope. I sent you a PM as I was wanting to look for the 909 amps you were talking about to add to my system and use my HD AVR as a Pre/Pro when I remodel the den and open it up.