Dynavector tube gear

[NOSValves]

Anyone know that the phono cartirdge company Dynector made tube gear in the late 70's? I had a customer drop off 4 different pieces a week ago and man is this stuff well built... He dropped off a DV3000 Gold preamplifier, DV8250 stereo power amplifier and a pair of DV8100 mono blocks. All 4 pieces have been in storage for a couple decades...I guess they were his fathers.

Pretty neat stuff the preamp works perfectly after fixing a few mechanical control problem, cleaning all contacts and then bringing it up on a variac over many hours. Preamp uses 4 12AU7's and 1 12AX7 per channel in a true dual mono design.

 

[Rex Everything]

WOW!...Had no idea.

That looks very nice. I like the gold on blue and the meters. Any amp pics?

 

[marantzfan]

Very cool.

 

[gadget73]

hm, interesting looking piece. Thats gotta be fun working on something thats fairly uncommon, just to see what else is out there.

 

[s-petersen]

I would like to see more pics of the pre and amps

 

[NOSValves]

The amps are just large very heavy black boxes common styling of that day and age that use 4 KT88's in PP with 12AX7 and 12BH7 front end driver/phase inverters. The first amp I tried could not make it through a slow variac without signs of serious capacitor leakage and red plating tubes so I ordered a ton of parts to replace the power supply and signal caps. They do have meters on the fronts also which is cool.

All 3 amps are identical the stereo amp is 50 WPC and the mono blocks are the stereo amp bridged for 100 wpc. Really large potted transformers. I put them away and will not be working on them until the first week in december but I'll take some more picture of them for you guys then. My bet is they sound great when working properly. The preamp sounds really good considering all its functions, tone controls multiple stages and so on. The tone controls are defeatable but I actually think its a bit sterile in the defeat position.

 

[NOSValves]

Oh and the first amp was equipped with a quad of original GEC KT88's that all test fine! I'm pretty sure the other two amps have the same from peaking through the vents..

 

[Kegger]

I love the look of the preamp, any chance of some nuddies?

 

[NOSValves]

Kegger yea I'll take some more when I remove the preamp from my system to do some final operational repairs before the customer picks this stuff up. My hope is that it will play without issue for 3 weeks so I can keep from actually having to complete disassemble it for recapping. When you see the pictures you will see why I would rather not have to tear into it. The power supply is no big deal but the front end circuit boards are really burried in layers of engineering that was not designed from a repair later mentality. With the preamp tubes only experiencing 200V max and the parts being rated at 600V I serious doubt they will develop problems with the entended slow variac job I did on it.

I had no documentation on the amplifier at all but I wrote dynavector and they sent me a generic manual for the DV8050, 8250 and 8100 that included a schematic of the 8050. I was just giving it a serious look and this is not a conventional PP design after all. They call it "simple ended push pull" whatever that means LOL!! I'm still trying to decipher how it works.

Check it out.

 

[NOSValves]

This darn forum compresses photo's when you upload them. The schematic is not all that legible because of it. If anyone wants an uncopressed copy email me at craig @ nosvalves.com (remove the spaces)

 

[zandru]

Congrats,

A Fantastic piece of equipment. Looks to me like it operates in a selectibale dual / mono mode.
Might I be correct in saying so?.

Your Dynector DV 3000 surely is a well appointed robust unit which appears to be in near mint condition.

It was very generous of you to offer it to me. I will swing by tomorrow to pick it up.

 

[NOSValves]

Well I'd imagine the real "owner" of it might be upset if I gave it away .... This isn't my gear... I repair/refurbish audio gear as a business.

 

[jtnfoley]

This darn forum compresses photo's when you upload them. The schematic is not all that legible because of it. If anyone wants an uncopressed copy email me at craig @ nosvalves.com (remove the spaces)

File hosting services like tinypic can upload to arbitrary sizes, and you can embed here with IMG tags.
I always do this in forums, rather than burden the forum owner with the load or have to deal with restrictions caused by those load concerns.

 

[NOSValves]

Grumpy can afford it

 

[zandru]

File hosting services like tinypic can upload to arbitrary sizes,
and you can embed here with IMG tags. I always do this in forums, rather than burden
the forum owner with the load or have to deal with restrictions caused by those load
concerns.

That's a good Idea John Foley.

I"m about to nix flickr in favor of my own dedicated website to post HI-Res photos
wih AK numbered thumnail photos corrosonding to the said linked website.
This for the time will minimize AK's finite storage capacity. Our fellow members
might consider this type of option that will help keep AK's websites from locking
up every so often.

 

[audiodon]

Stuff looks like it's for the pro/studio market.
Simple-ended. Whodathunkit?

 

[Stephen J]

Oh and the first amp was equipped with a quad of original GEC KT88's that all test fine! I'm pretty sure the other two amps have the same from peaking through the vents..

I only need 4 .. :yes:

 

[thefragger]

Waiting for the good pictures...

 

[zandru]

Stuff looks like it's for
the pro/studio market. Whodathunkit?

Audiodon,
You just might be right on the money.

The dual mono design suggests AM radio broadcast gear which allows
for a "No hassle" convenient operational control over two turntables.

 

[Dandy]

Stuff looks like it's for the pro/studio market.
Simple-ended. Whodathunkit?

If they were made for this market, and therefore in small numbers, it would be all the more interesting to see how they were constructed and the passive components used. Thanks for the promise of some pics in due course.