Graham,
That was a terrible sounding amplifier! I had one, bloody awful.
The Citation 12 is a very good sounding amplifier, as is the JLH 10W, and any of NPs designs.
Hugh
That was a terrible sounding amplifier! I had one, bloody awful.
The Citation 12 is a very good sounding amplifier, as is the JLH 10W, and any of NPs designs.
Hugh
With all due respect Hugh (as your posts are always humble and courteous), I have to disagree with you there.
The JLH10W amp sounds like the technology it uses - ie about 50 years old and very mediocre. I built one channel on veroboard a few years back using modern output devices (MJL21134 I think - the number escapes me) and my friend independantly built one channel on a PCB he designed and using the original specified output devices. They sounded identical - both course, muddy and with no low bass and grainy top end (and of course not enough power). I can't imagine why they have a cult following except by oldies with wornout ears that are used to huge amounts of second harmonic and general mediocre performance of valve amps of their time.
Cyclotron, I've got two eti5000 amps at home that were built in the 80s. They still work beautifully and go loud effortlessly. I've never seen any oscillation despite the Noble resistors (though I think they do have those stability caps you mentioned). And they are the only MOSFET amp (apart from the 6000) I've heard that can make music enjoyable.
There, I've had my say! Cheers guys!
The JLH10W amp sounds like the technology it uses - ie about 50 years old and very mediocre. I built one channel on veroboard a few years back using modern output devices (MJL21134 I think - the number escapes me) and my friend independantly built one channel on a PCB he designed and using the original specified output devices. They sounded identical - both course, muddy and with no low bass and grainy top end (and of course not enough power). I can't imagine why they have a cult following except by oldies with wornout ears that are used to huge amounts of second harmonic and general mediocre performance of valve amps of their time.
Cyclotron, I've got two eti5000 amps at home that were built in the 80s. They still work beautifully and go loud effortlessly. I've never seen any oscillation despite the Noble resistors (though I think they do have those stability caps you mentioned). And they are the only MOSFET amp (apart from the 6000) I've heard that can make music enjoyable.
There, I've had my say! Cheers guys!
Yes, now I "remember". Terrible sounding amplifier.AKSA said:
When he snaps his fingers I will buy an AKSA amp.
Then I will impersonate a chicken.
Hi Owdeo,
Thank you for your gracious post!
I'm not so humble I can tell you. Just good on a keyboard.......
I'm surprised you didn't like the JLH - there'd be many here disagree! But one thing is for certain, I like chocolate, you like steak, she likes oysters - everyone is different, thank God.
I built an ETI5000 back in the early eighties (cripes, am I that old now??) and thought it was the bees knees until I heard a few tube amps. Then in earnest in the mid-nineties I started R&D on amp design and realized abruptly that it was quite coloured, and a bit harsh. Mine was stable, too, but nowadays I've given up mosfets for Class AB, and use only bipolars, which have come a long way in linearity and robustness in the last 15 years.
Don't knock the 'oldies with worn out ears'. As people age, it seems to me more difficult to fool them with slick designs. They keep going back to 'natural' sounds, and definitely know what they like. All this as the ear clearly deteriorates; very strange.
Some people love second harmonic, others see it as 'muddy'. I'll reserve opinion, but I do think that the recording process often strips away some of the higher harmonics, including H2, leaving the sound thin and dry. Adding a bit in the right proportions can restore some of the original sound. In these circumstances amp design becomes more a recipe than a science.........
Cheers,
Hugh
Thank you for your gracious post!
I'm not so humble I can tell you. Just good on a keyboard.......
I'm surprised you didn't like the JLH - there'd be many here disagree! But one thing is for certain, I like chocolate, you like steak, she likes oysters - everyone is different, thank God.
I built an ETI5000 back in the early eighties (cripes, am I that old now??) and thought it was the bees knees until I heard a few tube amps. Then in earnest in the mid-nineties I started R&D on amp design and realized abruptly that it was quite coloured, and a bit harsh. Mine was stable, too, but nowadays I've given up mosfets for Class AB, and use only bipolars, which have come a long way in linearity and robustness in the last 15 years.
Don't knock the 'oldies with worn out ears'. As people age, it seems to me more difficult to fool them with slick designs. They keep going back to 'natural' sounds, and definitely know what they like. All this as the ear clearly deteriorates; very strange.
Some people love second harmonic, others see it as 'muddy'. I'll reserve opinion, but I do think that the recording process often strips away some of the higher harmonics, including H2, leaving the sound thin and dry. Adding a bit in the right proportions can restore some of the original sound. In these circumstances amp design becomes more a recipe than a science.........
Cheers,
Hugh
AKSA said:
Good post.
Perhaps the physical mechanism of the ear deteriorates, but the processing capability is being constantly refined with experience and compensates even more becoming an even more powerful tool.
Cheers
SC 480
I have just about finished building a SC 480 and now I read these comments. Is it really that bad? Have I wasted my time/money?
Is it the design or would replacing the transistors help?
Any thoughts would be appreciated.😕
I have just about finished building a SC 480 and now I read these comments. Is it really that bad? Have I wasted my time/money?
Is it the design or would replacing the transistors help?
Any thoughts would be appreciated.😕
don't panic
Hi Phil,
I'd say don't worry about it. Depending on the rest of your system, you may not necessarily be able to notice any deficiencies in your amp anyway.
Listen to it and if it sounds ok to you then be happy 🙂 don't worry too much if others personally don't like it, everyone has different tastes. Just see above how Owedo and Hugh don't agree on a particular amp (and Hugh has designed some very highly respected amps!!!)
Get some enjoyment out of it and when you feel like you need to quench your thirst for something better start looking at your next project. Hell I've had a playmaster series 200 for the last 16 years, and I'm not about to throw it out, I'm sure a lot of people would say that they hate it, but I'm relatively happy with it. I still beleive the biggest deficiency is in my speakers, so until I fix that I figure there no point upgrading my amp.
I started this thread because I'm considering changing from 3 way speakers to two way with stereo subs and would need a new amp to drive the 2ways and would use the series 200 for the sub amp.
If you really aren't happy after listening to your new amp, see if Eric can give you a hand, he said earlier that you can make some pretty basic changes that improve the ETI-480 substantially, but only worry about it if you don't think it sounds ok 🙂
Regards,
Tony.
Hi Phil,
I'd say don't worry about it. Depending on the rest of your system, you may not necessarily be able to notice any deficiencies in your amp anyway.
Listen to it and if it sounds ok to you then be happy 🙂 don't worry too much if others personally don't like it, everyone has different tastes. Just see above how Owedo and Hugh don't agree on a particular amp (and Hugh has designed some very highly respected amps!!!)
Get some enjoyment out of it and when you feel like you need to quench your thirst for something better start looking at your next project. Hell I've had a playmaster series 200 for the last 16 years, and I'm not about to throw it out, I'm sure a lot of people would say that they hate it, but I'm relatively happy with it. I still beleive the biggest deficiency is in my speakers, so until I fix that I figure there no point upgrading my amp.
I started this thread because I'm considering changing from 3 way speakers to two way with stereo subs and would need a new amp to drive the 2ways and would use the series 200 for the sub amp.
If you really aren't happy after listening to your new amp, see if Eric can give you a hand, he said earlier that you can make some pretty basic changes that improve the ETI-480 substantially, but only worry about it if you don't think it sounds ok 🙂
Regards,
Tony.
Nah, just do the appropriate mods straight off and enjoy it from word go.
Ask if you want details.
Eric.
Ask if you want details.
Eric.
I do some work for a production hire company.
One recent repair was to sort out problems with a talkback headset system.
The beltpack units were built from a SC kit, and worked sort of ok with some headsets but others headsets caused a loud low frequency hum/buzz out of the earphones on all beltpacks.
The cause of the problem was that whoever designed the pcb layout was a complete idiot, and has no understanding of amplifier layout and grounding rules.
The solution was to cut a couple of tracks and run earth wires to four points on the pcb.
The result is hifi sound that goes seriously loud and do not get nasty when pushed into overload which is a requirement for the usage of this system.
The electronic design is quite fine but bad layout caused this system to be a complete and unusable turd.
It is not guaranteed that magazine layouts are ideal, and in my experience every one that I have seen needs serious but simple help.
Eric.
One recent repair was to sort out problems with a talkback headset system.
The beltpack units were built from a SC kit, and worked sort of ok with some headsets but others headsets caused a loud low frequency hum/buzz out of the earphones on all beltpacks.
The cause of the problem was that whoever designed the pcb layout was a complete idiot, and has no understanding of amplifier layout and grounding rules.
The solution was to cut a couple of tracks and run earth wires to four points on the pcb.
The result is hifi sound that goes seriously loud and do not get nasty when pushed into overload which is a requirement for the usage of this system.
The electronic design is quite fine but bad layout caused this system to be a complete and unusable turd.
It is not guaranteed that magazine layouts are ideal, and in my experience every one that I have seen needs serious but simple help.
Eric.
Thanks for the advice🙂
I've had the amp running last night and it sounds better than the 1980's Technics system that I have got. I'm still using the Technics Cd and a pair of Wharfedale s900 speakers.( I think a speaker project is necessary)
I've been bitten by this DIY bug so I know I won't be completely satisfied by this amp, so wether to improve it or build a new(better) design will be the next question. What do you think?
Its great to be able to discuss this with people that know so much more than me.
Phil
I've had the amp running last night and it sounds better than the 1980's Technics system that I have got. I'm still using the Technics Cd and a pair of Wharfedale s900 speakers.( I think a speaker project is necessary)
I've been bitten by this DIY bug so I know I won't be completely satisfied by this amp, so wether to improve it or build a new(better) design will be the next question. What do you think?
Its great to be able to discuss this with people that know so much more than me.
Phil
I think your photo got lost in the ether.
If you can post schematic and pcb layout too would be useful.
Eric.
If you can post schematic and pcb layout too would be useful.
Eric.
PhilR said:
Don't mess with it too much, just enjoy it as it is (better than what you have, no?) and use it as a sub amp when you build some new speakers. It'll be relatively innocuous below 100Hz or so.
It is a mistake to make any conclusions about the SC480 based on the ETI480. They are completely different designs.
In my personal opinion, the ETI480 had some questionable design aspects such as bias stability and frequency compensation issues. From a technical point of view the old ETI-480 does not perform well at all. The SC-480, although I have not built one, looks like it is designed to perform well. The Silicon Chip artical states that the THD of the SC-480 is two orders of magnitude better than the ETI-480 design that it replaces. I cannot vouch for that info, but the plots showing THD of less that 0.01% look promising to me.
regards,
John.
In my personal opinion, the ETI480 had some questionable design aspects such as bias stability and frequency compensation issues. From a technical point of view the old ETI-480 does not perform well at all. The SC-480, although I have not built one, looks like it is designed to perform well. The Silicon Chip artical states that the THD of the SC-480 is two orders of magnitude better than the ETI-480 design that it replaces. I cannot vouch for that info, but the plots showing THD of less that 0.01% look promising to me.
regards,
John.
ive built a sc480 amp, sounds great.. but a beefier transformer is a definate.. i replaced the 135va EI core with a 300va toroid - the amount of 50/100hz hum was reduced alot and definately added to the soudn quality across the board 🙂
Re: 2nd thoughts
hi phil,u live in the same place as me!
im interested in what the amp sounds like,i started building an eti-480 then just left it,Im really considering an active system with either 4 class A ESP units or 4 chipamps depending on what i can afford
using a 350w plate amp right now with jbl15" 2226h.
http://www.geocities.com/xobt/
Cheers!
PhilR said:
hi phil,u live in the same place as me!
im interested in what the amp sounds like,i started building an eti-480 then just left it,Im really considering an active system with either 4 class A ESP units or 4 chipamps depending on what i can afford
using a 350w plate amp right now with jbl15" 2226h.
http://www.geocities.com/xobt/
Cheers!
sc480
Hi Mike
I've had my sc480 for a few months now, when listening to it I have felt that there was something missing in fact it didn't sound much better than most midi systems ie Technics, Pioneer. I was blaming this on my speakers which are Wharfdales.
I have since got a valve amplifier and the difference in sound quality is amazing. The distortion figures on this amp are nowhere as good as the sc480 so i dont believe figures mean everything when it comes to comparing the sound of different amps
I'm planning on using the sc480 boards in a 5.1 system for playing movies.
It would be good to find somebody who has built the ESP units as I suspect they will be superior to the sc 480.
With regard to the wharfdales I'm looking at replacing them with a pair of image speakers, these are made in NZ and I was wondering if you had heard anything about them.
This is off the subject but I saw the photos of Haywards Pt on your web site, its a wonderful part of the country.
Hi Mike
I've had my sc480 for a few months now, when listening to it I have felt that there was something missing in fact it didn't sound much better than most midi systems ie Technics, Pioneer. I was blaming this on my speakers which are Wharfdales.
I have since got a valve amplifier and the difference in sound quality is amazing. The distortion figures on this amp are nowhere as good as the sc480 so i dont believe figures mean everything when it comes to comparing the sound of different amps
I'm planning on using the sc480 boards in a 5.1 system for playing movies.
It would be good to find somebody who has built the ESP units as I suspect they will be superior to the sc 480.
With regard to the wharfdales I'm looking at replacing them with a pair of image speakers, these are made in NZ and I was wondering if you had heard anything about them.
This is off the subject but I saw the photos of Haywards Pt on your web site, its a wonderful part of the country.
PhilR,
Interesting comments on the SC480.
In my current setup, I find my SC480 it too clinical, and the thing that is missing is balls, but YMMV. It also seems to run out of puff when I turn up the volume. I still don't consider it a bad amp though, just I have three others that I prefer. (AKSA, DIGI125 and P3A) By coincidence (or not?), all three have a simple bootstrapped VAS instead of the CCS of the SC480.
I have a Elliott DOZ under construction so I can't comment on that yet.
BTW: On the SC480 (TO-3 version), I have replaced ceramic caps with polystrene and the PSU in non-standard: 2 x 160VA 28V toriods, 2 x MUR860 bridges and 4 x 4,700uf capacitors.
Interesting comments on the SC480.
In my current setup, I find my SC480 it too clinical, and the thing that is missing is balls, but YMMV. It also seems to run out of puff when I turn up the volume. I still don't consider it a bad amp though, just I have three others that I prefer. (AKSA, DIGI125 and P3A) By coincidence (or not?), all three have a simple bootstrapped VAS instead of the CCS of the SC480.
I have a Elliott DOZ under construction so I can't comment on that yet.
BTW: On the SC480 (TO-3 version), I have replaced ceramic caps with polystrene and the PSU in non-standard: 2 x 160VA 28V toriods, 2 x MUR860 bridges and 4 x 4,700uf capacitors.
Phil-
For sure its a great area id never been before. Recently i rode up whare flat rd and behind flagstaff and back home to centre city ,nice!
I too am interested in class A mosfet usage,DoZ/SoZ, JLH and hiraga. By the time ive studied and decided,il have enough money for one of them!
im not into HT(expensive)just music.Am building jbl 15" basshorn!
hit me with an email for audio-chat if wanted
http://www.geocities.com/xobt
my eti480 shrine ive just started 🙂
🙂
For sure its a great area id never been before. Recently i rode up whare flat rd and behind flagstaff and back home to centre city ,nice!
I too am interested in class A mosfet usage,DoZ/SoZ, JLH and hiraga. By the time ive studied and decided,il have enough money for one of them!
im not into HT(expensive)just music.Am building jbl 15" basshorn!
hit me with an email for audio-chat if wanted
http://www.geocities.com/xobt
my eti480 shrine ive just started 🙂
🙂
Attachments
- Status
- Not open for further replies.