Hello .
I have this Nad 306 that I really love but now I readed on different topics that old Nad models have very poor speaker protection and if the amp fails usually will also kill the speakers .
Maybe someone can take a look to tell if the speakers are safe using this amp .
This amp also have a relay but I'm not so sure what a good speaker protection really means regarding the schematic .
Also right now I also have a Yamaha A-700 and another A-720 model but Nad sounds better because the bass have more depth and there is more musicality .
Thanks
I have this Nad 306 that I really love but now I readed on different topics that old Nad models have very poor speaker protection and if the amp fails usually will also kill the speakers .
Maybe someone can take a look to tell if the speakers are safe using this amp .
This amp also have a relay but I'm not so sure what a good speaker protection really means regarding the schematic .
Also right now I also have a Yamaha A-700 and another A-720 model but Nad sounds better because the bass have more depth and there is more musicality .
Thanks
What speakers are involved, and for how long have you been using the NAD without “protection”? This amp model is over 25 yrs old, and while I don’t currently own any NAD products, I certainly did back in the late 70’s though mid 80’s, and can never remember damaging any of the dozens of pairs of speakers that rotated through my systems in those halcyon days. Car stereos were a different story back then 😱
But if you’re paranoid enough about it, and still love the sound of the NAD, there are several options for DIY friendly protection circuits - i.e. fully engineered circuits, PCBs and bills of material - that providing sufficient internal space might be able to be shoe-horned into the existing chassis. I’d probably prefer to add something like that than try to hack an existing circuit.
https://diyaudiostore.com/collectio...speaker-turn-on-delay-and-dc-protector-boards
https://www.neurochrome.com/product/guardian-86-2/
But if you’re paranoid enough about it, and still love the sound of the NAD, there are several options for DIY friendly protection circuits - i.e. fully engineered circuits, PCBs and bills of material - that providing sufficient internal space might be able to be shoe-horned into the existing chassis. I’d probably prefer to add something like that than try to hack an existing circuit.
https://diyaudiostore.com/collectio...speaker-turn-on-delay-and-dc-protector-boards
https://www.neurochrome.com/product/guardian-86-2/
Can you go up the circuit so we can give you a good advice?
Here you have the link.
https://www.hifiengine.com/manual_library/nad/306.shtml
If the NAD 306 really has a protection circuit with relays, it is much more effective (it cuts the current of the output stage) than a 2 amp series fuse before a peak or high crossing distortion .. A tweeter goes to a better life with much less current than 2 amperes, the Nad 3020 had (I still enjoy) a circuit of Soft Clipping, if the 306 has the same, leave it always activated.
Here you have the link.
https://www.hifiengine.com/manual_library/nad/306.shtml
If the NAD 306 really has a protection circuit with relays, it is much more effective (it cuts the current of the output stage) than a 2 amp series fuse before a peak or high crossing distortion .. A tweeter goes to a better life with much less current than 2 amperes, the Nad 3020 had (I still enjoy) a circuit of Soft Clipping, if the 306 has the same, leave it always activated.
Well, you already have the circuit, and yes, it has protection by peaks of distortion by crossing (clipping) and by short circuits (3 relays) so the only recommendation that I would give you is that you do not abuse loads too low, I always distrusted the 2 theoretical ohms that many manufacturers claim to endure without problems.
https://images-na.ssl-images-amazon.com/images/I/51D0IxEftaL._SX404_BO1,204,203,200_.jpg
The schematic snippet above cuts-off much of the TA7317P chip, which with Q445 et al does provide a "complete" protection against both over-current and dangerous DC offset.
Thank you all for your helpful responses the schematic of this amp is very complex .
The speakers that I'm using are 6 ohms .
This amp also have the soft clipping function but I prefer to not use this function because is affecting the sound in certain ways .
I was getting a little paranoid after reading on different forums that during 90s many NAD amps had very bad or non existent speaker protections .
The speakers that I'm using are 6 ohms .
This amp also have the soft clipping function but I prefer to not use this function because is affecting the sound in certain ways .
I was getting a little paranoid after reading on different forums that during 90s many NAD amps had very bad or non existent speaker protections .
The cuts in the sinusoidal waves are the most dangerous for the speakers, especially the tweeters that are the ones with the most fragile coils. It is a kind of machine gun, ta, ta, ta, until it cuts into the thin wire ....
I would like to know with what speakers you are using it, because for you to notice the difference between the Soft Clipping connected or not, they must be of great quality. And you must also have a very good ear, I currently use the Nad 3020 as a preamp only, but when I used it as a power amplifier coupled with good speakers I did not notice any audible differences, to be honest...🙂
http://www.audio-supply.com/noun/soft-clipping/
The other great danger are the connectors of pressure of cable speakers that were used at that time, which bite the bare wire. It is very common to touch each other when moving the amplifier, causing the destruction of the power transistors. I did not read it on the internet, I was a witness ...😀
I would like to know with what speakers you are using it, because for you to notice the difference between the Soft Clipping connected or not, they must be of great quality. And you must also have a very good ear, I currently use the Nad 3020 as a preamp only, but when I used it as a power amplifier coupled with good speakers I did not notice any audible differences, to be honest...🙂
http://www.audio-supply.com/noun/soft-clipping/
The other great danger are the connectors of pressure of cable speakers that were used at that time, which bite the bare wire. It is very common to touch each other when moving the amplifier, causing the destruction of the power transistors. I did not read it on the internet, I was a witness ...😀
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Thank goodness you don't read all kinds of alarmist things on the internet about capacitors and such like and start having nightmares and worry yourself so much you have to attempt to find solace by sharing your angst on an audio forum.
I try not to consume snake oil, and yes, I like to share, thank God, I think that's good, or not ? 🙂
But share anguish is for forums of psychoanalysis or philosophy ...😀
I think, therefore I exist ....😉
But share anguish is for forums of psychoanalysis or philosophy ...😀
I think, therefore I exist ....😉
I use some project speakers designed by me with the help of a few friends and highly extensive research so every crossover is outside the speakers . Is a 3 way using best PIO caps so because the crossovers are to big they have their own box separate from the speakers boxes and also the speaker drivers are modular having their own box so I can change the tweeters or the mid drivers on the fly .
I can hear everything but this is not really a quality because such speakers are hungry to have the cleanest amp and every sound distortion will be evident .
Also I can hear difference by changing different caps which many will find ridiculous ..though with normal consumer speakers will not hear any from those details so I don't think I'm crazy lool
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Well, in that case you do not have to worry too much about the protection circuits since it will be easy to solve some damage of the speakers.....
And if you want to take a step further in the search for musical nirvana, try a valvular push pull. You should not spend too much, any properly reconditioned Dynaco St 70 will make any transitorized of similar power pale (and I encourage you to say that up to one of twice the power, given that the watts of a valve, - for some reason that never It's clarified thoroughly - they sound louder than the watts of a solid state.
But I am giving advice in the wrong thread. Sorry.
https://www.hifiengine.com/manual_library/dynaco/stereo-70.shtml
There is really so much difference between valve and integrated ?.
How do you perceive this difference ?/
By playing with different caps combinations I was able to push the integrated sound to a very warm big rich sound which is alsi very precise.
Now I din not imagine something better and the valve sound to mock the integrated but I will look after Dynaco St 70.
How do you perceive this difference ?/
By playing with different caps combinations I was able to push the integrated sound to a very warm big rich sound which is alsi very precise.
Now I din not imagine something better and the valve sound to mock the integrated but I will look after Dynaco St 70.
There is really so much difference between valve and integrated ?.
How do you perceive this difference ?/
By playing with different caps combinations I was able to push the integrated sound to a very warm big rich sound which is alsi very precise.
Now I din not imagine something better and the valve sound to mock the integrated but I will look after Dynaco St 70.
To my ears the amplifiers Valves vs. Transistors have several virtues and a few disadvantages.
But I do not intend to start controversial here, it does not correspond, this thread is of solid state, you would have to start a new thread, which probably already exists in this forum, and if not, you will find a lot of information on the web.
Only an OT: My amplifier to valves allows to switch between triode and ultralineal the exit stage, and since I have 3 quads of different types of valves, it gives me the option of choosing six different types of sound, always with the same acoustic cabinets. This is a lot of fun!
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