The all new ET7-2 Pre-amp is here

[admin]

The hum is like a bad cable...that kind of hum. Yes, it is a 60HZ Hum

Thanks,
R.

If it's 60 hz, it could also be a ground loop. I would rule that out first before component trouble shooting.

[roberto]

The question is, why only the R channel? if there is a ground loop, both channels should be contaminated, the left channel is clean!...thanks admin.
Rç

[roberto]

The ground is common for both channels...somewhere I have a broken ground contact.

[admin]

The ground is common for both channels...somewhere I have a broken ground contact.

Possible. Remind me what you are running as your amp now. If they are monoblocks, it stool could be a ground loop.

I've had terribly unpredictable experiences with ground loops in my system. No rhyme or reason. Do you have a ground loop isolator to put between the preamp and amp?

[AnotherJohnson]

Last I knew, he was running a single chassis Classic, I think 120 SE.

I think he is on the right track, and the low hanging fruit is the interconnects, followed by the RCA sockets. Solder joints, leaking caps, etc

[roberto]

Believe it or not, it was a 5751 also a 5965A, both were acting strange. Now the noise is way down, still there is a noise at -75dB...also the frequency is down at 50Hz, this is a bad cap...I will chase this with my scope.
I am taking apart the unit to reach the printed circuit board. If I tape, I get an odd noise in my dB meter only in the right channel. This could a possible problem too.

Both channels measure the same level .5dB while moving the volume control. With music you can't hear a difference in level. Bringing my test tone oscillator, their behaviour are the same, but at 50Hz the right channel drops at -13dB.

I have to leave now, tomorrow I will continue the story.

[AnotherJohnson]

Well the tubes are always among the lowest hanging fruit.

Can you imagine how a P9 will sound when it’s 38 years old?

[roberto]

Bad news for me...the truth is that this unit has been cannibalised before...I did not repair this unit before and I never sow how bad it is...Conrad Johnson handles this with much proud, because what it is here, I don't know how the unit produces sound. The technician was a butcher, definitively.

I will leave it as it is, will see if I can look for bad joints, change a short 4uF@16V, and will do a better inspection tomorrow with the sun light.

I think that it is better to go back to the ugly sound of SS, than put this poor baby to work. It is really damaged.

Thanks to all for the valued help...I am blessed here!!

Happy listening!

[AnotherJohnson]

Seriously Roberto, the Nuforce P9 should not be too painful. It is a nice unit for its modest price point.

It will make you even happier when you get your new ET7s2. You will be transported to another world!

Keep up the good work!

Edit: Regarding old preamps or amps from ANY manufacturer. They do not sound the same today due to parts aging. And fixing one is like playing a game of whack-a-mole.

I think it is often cheaper, and nearly always sonically better to advance at least to the 21st century. I live the old gear … but it’s for the nostalgia. You can only listen to nostalgia for so long.

[roberto]

Again, TX AJ and Admin,

Getting back to the PV-5, I did change that 4.7uF that was in short. This was causing the problem. The noise is gone and also the bass is back. It's incredible what a simple 4,7uF can do.

The unit is now working, but I do not trust in it. I hate when I see people with knowledge that work so bad, that they do not mind the quality of the work done. It's a shame to see this.

I said that now I am listening to a Sonic Frontiers SFL-1. This is a good unit. Of course not at the level of the ET-7, but the sound is nice. I'm thrilled that being it into the storage room, works so nice, not even a noise.

[admin]

Glad it was an "easy" fix. Look forward hearing the comparison reviews.

[SteveFord]

[/quote]
I would have to agree. The truth is that this is the first time in my audiophile career that I feel all my components are top notch. This is not to say I didn't like the sound of my system in the past. But I always had older or mid-range components that I new could be improved with better quality gear. I loved my CJ Evolution 2000 amp, but again, it was pushing 3 decades. Loved the PV-12AL, but new that CJ had better modern offerings that would out perform.

It feels nice to know that I am really getting close to the border of what a stereo system can produce. Yes, I'm sure people will argue that the 30.7's are better than the 20.1's, or the GATII is superior to the ET7s2, and not saying that isn't true. But there are truly no overt "weak links" in the audio chain at this point and that's a first for me. I am really enjoying the tunes right now. Just very happy how the new equipment that has entered my system in the last 1-2 years has taken everything to a higher level.
[/quote]

There's ALWAYS something better coming down the pike.
Amp, speakers, preamp, motorcycle, whatever.
The trick is to get to the point where you're perfectly happy right where you are and forget the rest of it.
Sounds like you're there.

Magnepan does have some new speakers coming out (eventually) to replace the 3.7s, though.
Hmmm...

[roberto]

Jeff told me: Friday we are going to ship the ET7S2. I thought it was going to be today, but it looks that it is going to be the next Friday. I’m going to have a surmenaje because of the anxiety.

Happy listening!

[AnotherJohnson]

[admin]

Ahhh... Don't worry, good things come to those who wait. It will all be worth it. I've been listening to the ET7s2 for a few weeks now and it's just amazing. I have recently not been completely cutting the power with my APC voltage regulator as apparently it's recommended to keep the unit in standby mode and not fully cut the power. I think this is also true for the Holo Audio May DAC so hopefully this is "healthier" for both units.

[roberto]

The stand by mode has a dedicated power supply of +5V and what is does is simple. It cuts out the filament voltage that goes to the tube and this is the reason why while turning the unit on, the heater timer starts and the tube turns on. The remain power supplies ( there are several power supplies ) are on, and because the tube is not really on, the consumption is nothing.
The voltage on the circuit is very important because being the pre amp having a kind to be alive, with to changes is temperature of the room, it is stabilised for these temperatures do not affect it.

Admin, I do know what I am going to have soon in my system, it is just that I am too anxious. The other thing that worries me is at customs...I hope everything goes easy and fast.

Happy listening!

[AnotherJohnson]

Ah, customs … the bain of international sales everywhere.

We even have it for inbound items here in the US. When I was building my LP12s, the parts would have to clear leaving the UK and again entering the US.

I spent many an anxious moment …

I hope it goes very smoothly for you. When it’s over, you’ll be glad.

[admin]

Let's hope that it doesn't get held up in customs for too long. I've ordered a couple of things from overseas in the past few months and they arrived relatively quickly so let's keep our fingers crossed.

[roberto]

Thank you my friends!

Our taxes are CIF. not FOB. Freight and insurance is a must. I have an address in Miami and it is a forwarder address. Anything that gets there under my name, I will have it in my hands in about 15 days, which it is not too bad.

Oh well, such is life in the tropics. This is Paradise, so patience is a virtue. I have to drink a lot of that!

Enjoy those wonderful musicians playing for us in our own home!

Happy listening!

[AnotherJohnson]

CIF was a new term for me. Maybe some others are also new to the term. So here’s a comparison of CIF vs FOB.

https://www.thebrimichgroup.com/fob-vs- ... nsibility/

It sounds like the buyer benefits… it may be behind the idea of having an official exporter/importer

In my dealings with overseas suppliers, FOB has always been assumed. That put me at risk on shipment, but I wonder now if I might have been entitled to CIF or its airborne equivalent.