Ampeg V4.com

Thanx


EDIT:

I coulden't find it on their page so I emailed them.

Last edited by Casey4s (2010-09-26 21:47:35)

Thanks for the info,  WoW!  $90   I wasn't expecting that at all.

I may need a plan B.

I'm not familiar with the layout, but I just found out about the V9, which seems to do the similar thing with discreet inductors(?) so it's not altogether strange - seems simplified too (only one tube involved).  I'll have to check it out via spice and compare.

http://www.drtube.com/schematics/ampeg/v9pre-jp.gif

It's the same...the large transformer/inductor is total 800, with taps at 100 and 300. You can see how they did this on a V4 schematic.  If you check the V9, you see they used 3 separate discrete inductors - one 800, one 300, one 100. But you could arrange a configuration with a 400, 300, and 100 discrete inductors in series, too.  Same result.

To be honest, I'm clueless about inductor specs (does more than the inductance matter here?)

But...

http://www.mouser.com/Passive-Components/_/N-5g73/   --->
http://www.mouser.com/Passive-Component … /_/N-5gb4/

After that, I'd assume common mode or RF inductors...but I'm lost after that, if not before!

Mesa used discrete inductors in the graphic eq section of the mark series... the values aren't exact,  but you could get pretty close. 

http://www.tubeampdoctor.com/index.php? … 545dffc742

note: if you call up mesa direct, you could probably get the parts cheaper than buying them from TAD.

I just heard that Ampeg is reiisueing the V9 to original specs and drawings, I wonder if they can sell me one as a replacement part?

hangman wrote:

hadn't heard that they were doing that.   they still use an 800mh inductor in the SVTs  but there are four taps, and thus different frequencies.  if that doesnt bother you, you could order that one
part number is:94-602-32

Thanks for the part number, I'll have to eMail Ampeg and see if I can get that one.

This is a scratch amp build so I am pretty flexible, I just got the pre amp drawing set up last week and the power supply today.

I have plenty of time so I am going to check every lead I can get, I am still sourcing parts at the moment.

I think that $6 x 8 + Shipping = $50+, and who knows what their specs are...or how they'll sound.

I just did a quick search of Jameco, and they have an assortment of small toroidal inductors (for example) for much cheaper than that. I'd rather take chances on three to eight of those at $1 a pop than $6 each for eight!  Also, don't sweat the inductor spec/listing is exact. The transformer is 20% tolerance at best anyhow, inductors are notoriously variable.  If you're losing sleep over accuracy, buy two of each of the closest to 100/300/400 you can find, measure the actual inductance, and pick the closest ones, if you like...

Even if, in the end, you end of going for the all out mercury or heyboer route, buying some of the above kind (they're like $1 each) or a couple varieties of cheap ones might help you experiment...and help you get to know more of what you're looking for if anything, beyond just inductance value.

In the end, if you want the easiest and most similar way, I'd get the MM and pay the money. Or heck, find a DOA V series amp, yank the toroidal out, then sell the rest for parts around here (heresy, I know...)!   The all-metal knobs sell on fliptops for $25+ each(!?)  And it's hard to find those rocker switches.

And, if you just want the mid control, well an op amp could do this pretty well too....

Last edited by Liquids (2010-09-29 19:58:09)

Casey,  we are a service center for ampeg, and I gave them a call and ordered an inductor for you if you want it.  I'm waiting to hear back on shipping charges from them,  but not including shipping the unit is only $15. 

email me if you want it.

-steve

Got the unit in,  $20+shipping to you (its small so it shouldn't cost much) let me know

Here's what I am doing with this inductor. The design is not 100% finished but pretty close. I need to tweak a few values in the preamp yet.

I've been working on the schematics for 4 days, as soon as I get that inductor I can start the layout. I have no clue what it looks like or how big it is.

V3 wil be a 12AU7 or 12AY7

Last edited by Casey4s (2010-10-22 03:54:05)