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[dumbangel]

http://www.tab-funkenwerk.com/V78.html

I remember you once wrote the original V-78 were your favourite of the V series. How about these new ones?

[Fletcher]

So far, I'm quite liking the TAB/Telefunkenwerk "V-78/M".  So far it seems to have a very interesting midrange character that I have found to smooth out some of the harsher mics in my collection but without making the 'smoother' sounding mics [like 4038's, etc.] seem dull.  It's kind of an interesting phenomenon.  The unit I'm playing with is a proto-type... the actual production units should start arriving the first or second week in July.

I have no idea how it does what it do... but it does and I'm glad.

[arimaka]

Seems like an interesting pre...

Does the v78 version have a Hi-Z input as well?
if it does is it the same as the DI in the 71?

Thanks
Manuel

[Fletcher]

Nope... the V-71 is the DI, the V-78M is the pre-amp... no DI at this point... though I will raise the question with Oliver.

[Oliver Archut]

Does the v78 version have a Hi-Z input as well?
if it does is it the same as the DI in the 71?

Hello Fletcher, hello Manuel,

It is quite difficult to change the V72/78 circuit over to a DI box due to the impedance/frequency dependent feedback network that is needed for disk type input x-former.

Sure you can disconnect the input x-former and just hook to the grid of the EF804/806s but than you loose 6db/octave above 9K and also the longer connection to the grid increases the S/N ratio to an unbearable -60dB.
One of the biggest problem with low tech modified historic V72 units.

Considering the fact that the V78 is guaranteed -90 dB self noise, it would be a shame just to place a toggle switch and switch from x-former to 1/4 inch.

In order to switch the x-former to 1/4 inch, in the V72S we use a 5 decked switch with help of a dual relay to make all connections like feedback resistor and feedback caps. grounding, etc.  the switch by itself is about $50 and the wiring about one hour.
My decision to keep the V78 affordable outweigh this additional feature, and than most of our V72S users got a V71 so they could dedicate both channels of the V72S as a mic pre....

I hope that helps your questions.

Best regards,

Oliver

[arimaka]

Thanks a lot for your great explanation

Looking forward to purchasing one of your products in the future...

Manuel

[hollywood_steve]

Sounds like another "must buy" piece of gear.  Several years ago I sent a V78 that I had just purchased up to Tab-F to be rehab'd.  Since then it has been my favorite mic preamp; fantastic sound and huge amounts of gain.  The only problem was that I record using stereo mic arrays most of the time, so the V78 wasn't getting as much use as it should.  But now I can purchase a brand new two channel V78!

(somebody ought to issue a moratorium on cool new products - there is just too much great gear out there right now)

[dumbangel]

Do the V72, V76 and the new V78 sound very different?

I heard that the V72 has an artificial rise in the highest frequencies, which the V76 hasn't.

[Oliver Archut]

The historic V72 (IRT) was speced from 40 to 15k Hz +0/-0.5dB, the historic V72S (only 300 or so made) is same as the V76S, 20 to 20k Hz.
There are several different V76 version from 80/120/M/fr about 40 to 10k or 15k and T (5Hz to 100k Hz).

Even the V76 is from a technical point two cascaded V72, were input x-former has the same disk winding technique but 1 to 30 ratio vs. V72 1 to 10, and V78 1 to 20, the sounds quite differs, were V72 is quite clear with a good low end, the V76 is quite dark with a killer low end. The V78 hangs somewere inbetween.
All proper historic working units should not have a rise at all.

Most home fixer upper V units, were someone just remove the frequency filters have a rise at about 8k to 12k with 6 to 8 dB on octave, depending on the revision (there are about 10 revisions in x-former); also compromising the S/N ratio.
In most cases if a hard 48V supply is installed the x-former gets pre biased (and you destroy the input x-former over time) so you lose everything below 300Hz, so there is a quasi artificial high end rise. All historic tube V series modules need a ramped (5 sec.) 48V supply in order to work and work proper for a long time.

The new V78M is based upon the same x-former we use in the V72S (identical in winding, core material to the historic V72S with changes in insulation material to insure a longer life), like the historic V72S no frequency filters are need, but with a few minor changes in circuit tree, to offer a wide sweep from classic V sound to modern colored sound.
In -60 dB (input sensitivity/impedance selector disconnected) the unit holds up to a proper rebuild V78. If you looking for a V76 you need to get a V76, if you looking for a V72S you need a V72S, even the differences are subtle...

Hope that helps you,

Best regards,

[echorec]

Oliver Archut wrote on Wed, 14 July 2004 04:33

...V72 is quite clear with a good low end, the V76 is quite dark with a killer low end. The V78 hangs somewere inbetween...

Great info as always, Oliver. Where would you put the V77 in that comparision?

[Oliver Archut]

The V77 is like the V78 a slightly modified V72, but the input x-former is 1 to 40 and even a disk type design it has a different sound on its own. The power x-former is also different than the V72, but more for reasons of better S/N ratio.

Historical speaking V77 were only used as buffer in output channels (final two tracks) in Siemens/Telefunken consoles, and in Masting application before you drove a Neumann lathe. The sonic resolution is more detailed if you mix down complex signals, mostly depending on the fact of the x-former. So the sound is somehow V72 like but with different mid range.

If used as mic pre it sounds quite nice, but you can overdrive it  quite easy due to the high self gain, so not to many people use it and not to many were build....

Best regards,

[echorec]

Thanks Oliver,

I just visited Fletchers site and saw the price of your V78. I must say that the price was lower than I had expected. Are they shipping already?

[Oliver Archut]

Up to this point we send out five units, three prototypes for dealer evaluation and two pre production units for people that could not wait....

I hope that the first batch will be at Fletcher latest end of this month, I am currently recovering from a major heart surgery so, some things are delayed...

Hope that helps,

Oliver

[arimaka]

Oliver thanks for making great gear! your pre will be my next purchase... as soon as I get some money!!

hope your recovery goes well...

[dumbangel]

Oliver,

just one more question. Can you tell us more about that input sensitivity/impedance selector that you mentioned?