The TA-N7 is a masterpiece. I respect the original design and when looking to improve certain things, I must make sure I do not desecrate the old, hence lots of planning and research is required before a viable solution can be implemented. Check out the Yamaha B-2 selector videos.
Amazing work! Fascinated with the detail of the improvements ! Is there any possibility to aquire the DC bias adjustement trim pot board developed by Mr. Oscar from Osuka Audio ?
I concur with your experience about the increase in bias and sound losing transparency and bass becoming imprecise. The sound also becomes threadbare and incisive if the bias is too much to low. I'm talking about the Sony TA-N80ES.
Thank you! Very informative! Answer please, if there is heating in the area of the block with V-fet, is this normal? What is the acceptable temperature ?
@@atelier_HiFi thank you ! very nice transistor i was planing to use KSC2690 that are very similar but 20 Watt Pd . Iam thinking if is better choise to replace all Sony small signal transistor like 2SA678 etc due for a lot defective found in the past .What do you think?
10:20 The new IEC receptacle does not offend at all - indeed it does look like it belonged there from the start. What were Sony thinking by not including one? Again, cost-cutting in the most incomprehensible manner. Those speaker cable binding posts look rather nice - what are they?
@@atelier_HiFi Thank you! I can only find the Acrolink FP-804(R) type from Aliexpress. No binding posts show up on the Acrolink site. Are these discontinued?
Frequency response and power response would be nice! Especially for these super huge output transformers? Are they output transformers? I wasn't aware this amp had those.
@@atelier_HiFi I want to share what happened when I bought two Sony TA-N80ES in the 90's due to the comment you made in this video about the bias. I was not as erudite back then so it is now that I realise the motives for which one amp sounded very detailed, exciting and tuneful while the other amp, being identical, did sound dull, lifeless with a undefined bass and lack of sparkling highs. I detected that one of them worked hotter. What was interesting is that, as you also say in the video about the misconception of the higher the bias the better, is that the cooler, less biased one was so superior sonically to the other that the only thing I could do with the 'bad one' was to keep it packaged in storage. In many occasions while reading Stereophile, I've seen amplifier designers blame bad sounding units with inadequate bias adjustments. Let the ear be the final judgement is an appropriate statement don't you agree?
By studying the schematic of this amplifier ..I have now a problem calling this a real VFET amp .. ..Where the VFET are only used as current sources ..How can they be involved in the typical VFET sound ????.Also if this was a high end amp ..Why didn't they use Fiberglass pcbs
True, it is not really a v-fet amp but a hybrid. They did not use glass PCBs because glass PCBs were not the norm back in the day. They were only available for really high end gear and test equipment. The Yamaha B-1, Sony TA-N9, some Stax, Luxman and Accuphase gear had them but very rare indeed. Fiber glass PCBs later became the norm but it was an exotic product in the 70s.
Stellar work, I appreciate the attention to detail. No stone left unturned. Thanks for sharing!
Thank you Connor. You are doing an excellent job yourself. I enjoyed watching your videos as well.
I'm going to subscribe to your channel! Your work on input /output connectors and AC mains input is totally professional. Impressive!!
The TA-N7 is a masterpiece. I respect the original design and when looking to improve certain things, I must make sure I do not desecrate the old, hence lots of planning and research is required before a viable solution can be implemented. Check out the Yamaha B-2 selector videos.
@@atelier_HiFi sure I'll do it!!
@@atelier_HiFi excellent work. In my humble opinion, the TA-N7 is one of the best amplifiers Sony has ever made.
one of the best restauration ever braavo
much appreciated, Thank you!
Hi Fi Squirrel!!!!! Awesome video!!!! Hopefully more to come.
I hope so too! ..and working on it. See my Sony videos too :)
Amazing work! Fascinated with the detail of the improvements ! Is there any possibility to aquire the DC bias adjustement trim pot board developed by Mr. Oscar from Osuka Audio ?
Nice job !!
thank you
What is your sweet spot for the bias?
I concur with your experience about the increase in bias and sound losing transparency and bass becoming imprecise. The sound also becomes threadbare and incisive if the bias is too much to low. I'm talking about the Sony TA-N80ES.
what's the sweet spot for bias? Service manual says 30-70mv
Thank you! Very informative! Answer please, if there is heating in the area of the block with V-fet, is this normal? What is the acceptable temperature ?
could you please tell me wich drivers transistor used instead of the old TO202 ? i seen you used TO126 . Thank you
yes, TO-126 work but you have to do the leg twist. Toshiba TTA004, TTC004 are very good candidates.
@@atelier_HiFi thank you ! very nice transistor i was planing to use KSC2690 that are very similar but 20 Watt Pd . Iam thinking if is better choise to replace all Sony small signal transistor like 2SA678 etc due for a lot defective found in the past .What do you think?
@@fabriziopettinao9773 I think you do what it is best for your unit. Best of luck!
10:20 The new IEC receptacle does not offend at all - indeed it does look like it belonged there from the start. What were Sony thinking by not including one? Again, cost-cutting in the most incomprehensible manner.
Those speaker cable binding posts look rather nice - what are they?
Yes, I like how the IEC receptacle turned out. The speaker binding posts are Acrolink.
@@atelier_HiFi Thank you! I can only find the Acrolink FP-804(R) type from Aliexpress. No binding posts show up on the Acrolink site. Are these discontinued?
Frequency response and power response would be nice! Especially for these super huge output transformers? Are they output transformers? I wasn't aware this amp had those.
Power transformers only. No output transformers.
For the next rebuild I will post more in-depth testing.
@@atelier_HiFi I want to share what happened when I bought two Sony TA-N80ES in the 90's due to the comment you made in this video about the bias. I was not as erudite back then so it is now that I realise the motives for which one amp sounded very detailed, exciting and tuneful while the other amp, being identical, did sound dull, lifeless with a undefined bass and lack of sparkling highs. I detected that one of them worked hotter. What was interesting is that, as you also say in the video about the misconception of the higher the bias the better, is that the cooler, less biased one was so superior sonically to the other that the only thing I could do with the 'bad one' was to keep it packaged in storage.
In many occasions while reading Stereophile, I've seen amplifier designers blame bad sounding units with inadequate bias adjustments. Let the ear be the final judgement is an appropriate statement don't you agree?
@@salvadorrodenas3071 yes, couldn't agree more.
@@atelier_HiFi thanks
By studying the schematic of this amplifier ..I have now a problem calling this a real VFET amp .. ..Where the VFET are only used as current sources ..How can they be involved in the typical VFET sound ????.Also if this was a high end amp ..Why didn't they use Fiberglass pcbs
True, it is not really a v-fet amp but a hybrid. They did not use glass PCBs because glass PCBs were not the norm back in the day. They were only available for really high end gear and test equipment. The Yamaha B-1, Sony TA-N9, some Stax, Luxman and Accuphase gear had them but very rare indeed. Fiber glass PCBs later became the norm but it was an exotic product in the 70s.
6:08 The question on everyone's mind is: what is the scale?