Carver silver 7: how to resuscitate them?

[ABilluminazione 4]

 

Good morning (?) to all,

I'm just new on this fantastic forum (but I read it since 2 years ago). I'm an italian sound engineer since 1990 in Bologna, the city of Ducati and Lamborghini. My english is very bad, so I invoke your understanding.

I have a pair of silver7 s/n 012, bought new in 1991, used for about 100hrs up to 1994, then never used.

Now I wish to resuscitate them, but I have some questions:

1- how can I proceed to turn on the amplifiers? I read that, not to damage the capacitors, I must use a variac, rise slowly up to 50v, remain at 50v for 1 hour, rise to 110v, remain for 1 hour, and finally go to 230v (the european voltage). Is this a correct procedure? Must I use a dummy load or an expendable loudspeakers? Must I inject an input signal?

2- My beautiful 3 years old daughter destroyed a 6550 carver signed tube. I think that it's better to replace the 6550 of the power supply, not the 7+7 used in the push pull circuit. Can someone tell me its position? The tubes are arranged in a 3x5 Matrix, as you probably know.

3- is this signal tubes position correct? From left to right: 3x 12bh7a, 1x 12bv7.

4- I have the schematic and original boxes but no owner's manual: where can I buy it?

Thank you very much!!!

 

 

 

[soulsurfer 110]

Welcome!!!

I've done this all of 2 times on old guitar amps in my 5 decades on this planet. This is how I did it (more than one way to do it).

(I found a version of the same technique online- but there are other techniques)

 

I made sure that the correct fuse was installed in the amp(s). Cleaned them up on the inside a bit to look for any obvious signs of abuse or failures (burn marks, already blown caps, missing bits, etc) 

 

Then I took a volt meter and measured the wall outlet voltage when it would be most stable (usually late evening/night). Then using the volt meter, measured the output voltage of the variac at unity. (or noted where unity was on the variac's meter--not always correct).

 

I didn't want to over power the amp.

 

Made sure that the correct ohm load was connected. (cheap speakers or dummy load).

No signal! Volume down as my guitar amps obviously had preamps.

You're amps don't need a signal.

 

Now the key is to give the caps some time to form at low voltage say 40% or so at first. Just slowly turn up the voltage on the variac in 5-10v increments...waiting for a few minutes at each point until you reach 40%.

Hold there for an hour.

 

Turn up the voltage at 5-10v and hold for 30mins. Keep doing that until you get to full voltage.

Hold there overnight. 

 

The next day I carefully turned down the voltage on the variac and turned off the amp- unplugged it from the variac.

 

Then I ran them for a few days at low volume with a signal going into it. I noticed that the sound changed over that time. Maybe your mileage will vary...but it seemed that the amps needed some time to 'recalibrate'. ??

 

Then I jammed away! No issues. I did take them into my local tech to have them 'gone thru' before I gigged with them. I'd do the same thing with home stereos that have been sitting for a while too. Just to feed my OCD.

 

 

 

 

[mbskeam 1,975]

2- My beautiful 3 years old daughter destroyed a 6550 carver signed tube. I think that it's better to replace the 6550 of the power supply, not the 7+7 used in the push pull circuit. Can someone tell me its position? The tubes are arranged in a 3x5 Matrix, as you probably know.

 

 

the center tube.

 

 

[aslan7 954]

Hey Vincenzo

 

Though I can offer you no help in your Silver 7t resuscitation quest, I can say welcome to the forum --officially.

 

Great to have folks like you on the Carver team my friend.

 

Ps-love the avatar!

[ABilluminazione 4]

Wow my friends.... Problem solved within 2 hours from my request... I need some slap to realize I'm not dreaming! This is feeling to be part of a real community.

Thank you, thank you very much!

I hope to be so helpful in the future for some other friends.

I'm waiting for the new, powerful variac (I've one of 300va, the new one is 2000va) I ordered two days ago, and I'll update you on the work in progress of my new living room.

 

[kingman 662]

Post some pics of those beauties!!!

[loner_t 2,568]

Wow my friends.... Problem solved within 2 hours from my request...  

 

It is good to see vintage gear alive and well. Also, welcome to CarverSite, ABilluminazione. 

 

We want audio picture porn! 

[ABilluminazione 4]

Hello to all,

I read the "how to insert photos" topic but in the space for text (this space) there is any toolbar on top...

[loner_t 2,568]

Hello to all,
I read the "how to insert photos" topic but in the space for text (this space) there is any toolbar on top...

 

Can you check THIS post (by Zumbini) for the steps to post pictures?  

[ABilluminazione 4]

yes. No toolbar. Only a blank sheet. I've win10 and Explorer.

[loner_t 2,568]

yes. No toolbar. Only a blank sheet. I've win10 and Explorer.

 

Sometimes Microsoft Edge on W10 causes issues. Do you have another browser - Chrome or FireFox? You can also find Internet Explorer via Cortana. Javascript renders some of the dialog, so check that JS is enabled.

[ABilluminazione 4]

ok, Tomorrow I'll try to download chrome, now it's 3am, time to sleep...

thank you all!

[4RUNNER 518]

Welcome. yes changing to chrome worked for me

[Belvedere2 232]

Welcome to the forum! Awesome amps. We all wish we could have some or at least hear some.

[dennismiller55 4,809]

With regards to inserting pictures, I had problems with Win8.1 and IE, so I went to Chrome.  I have no problems posting pictures with Win 10 and Edge.  In fact, I like Windows 10 and Edge.

[ABilluminazione 4]

Hi everybody!

Sorry for my delay, but this is a period of hard work, Touring with rock bands in clubs and beer festival (yes, we live sound engineer are like Gynecologists: we work where normal people have fun...).

1- Thank you for your suggestion about Chrome: it works perfectly.

2- The 2kva vaiac arrived to me, but I want to power on it with a inexpensive amp before than with the silver seven. I think that my experience may be of interest for people of this forum because here we have mainly vintage gears. I want to descibe my experience as accurate as possible, including all suggestions from you. Next week will be the "fire week".

3- I still have a question: is the sequence of signal tubes correct, as described in my first post?

Thank you very much!

 

[mbskeam 1,975]

From left to right: 3x 12bh7a, 1x 12bv7.

 

yes, From left to right: 3x 12bh7a, 1x 12by7a you can use non "A's". also.

[ABilluminazione 4]

to Mbskeam:

you are simply essential.

Thank you very much!! 

[Reese 52]

(duplicate message)

[Reese 52]

Bienvenuto al foro! (Ho studiato all'università' di Bologna per un anno, tanti anni fa.....Habitai a Verona per due o tre anni -- che meraviglia e' l'Italia!!!!

E' un piacere veder lei qui fra gli amici di Carver e suoni e sistemi meravigliosi!!!)

 

Reese

[Reese 52]

Bienvenuto al foro! (Ho studiato all'università' di Bologna per un anno, tanti anni fa.....Habitai a Verona per due o tre anni -- che meraviglia e' l'Italia!!!!

E' un piacere vedere lei qui fra gli amici di Carver e suoni e sistemi meravigliosi!!!)

 

Reese

[ABilluminazione 4]

Hi everybody,

to Reese: thank you for your kind words, but Italy is a land of big contraddictions...

At last, these are firsts pics of the double-face game field: for inhabitants under 3 years old and for over 50 years old. This is still a work in progress, the wood furniture is just a visible example for the eyes of who-will-decide (not me, of course), and I did not hook the silver7's up to the variac.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  

[PMAT 2,038]

Hot dang! The mother ship. Please do some close-up photos.

Thanks