Wojtek wrote:

In my old email to you I've mentioned that I have a pair of monster transformers 310-0-310 2A .I'd like to use them as a main transformer for bi-tri amp configuration ,with input choke load and folowing separating (tree branches) chokes for each amp .Duncan amps predict my B+ as 270-280V.Will this higher B+ degrade the sound noticably?

You will be burning the tubes at higher dissipating power, is it necessary? Sonically, I would keep the output stage at 200V-220V. HF and MF channels do not need more and if you go higher then it sound not good. The LF do not need voltage in most of the case and the dimpling would depends of your speakers, transformers and plate current. If you wish you might go for 250V at LF channel but you would need an extra secondary coil or a transformer as do so as you do not want to introduce any dropping resistor into the plate supple and rising the supply impedance.

Wojtek wrote:

Also did you custom order transformers for driver (bias) stage or it's a Hammond unit?

No I did not, however if you have 3 channel and drive them form one input choke than 100mA is already a more or less respectable current. Look for those stray fields…. And partially among other pieces of magnetic.

Wojtek wrote:

Last thing;coupling caps . I'm out of luck finding 4uF (or any) electrocubes so what else will fit the bill?

Use 2uF, 950 series.

The Cat

Wojtek wrote:

I'll experiment with the PSU a little. The transformes have only 1 Ohm DCR and total supply impedance for a channel would be ~ 45 Ohm (with two chokes in series) Imput choke looks like can take 1 A current!

Be carefully with the input choke that rated for 1A current. The inductance of a choke as I understand is rated for a nominal current. If you choke is 10H for instance at 1A and you will be driving it with 200mA then you might dive belong the critical inductance and it all will be worthless.

Wojtek wrote:

All Iron is mil quality and potted It is hard to pass iron like that and I'm poor .I may use a driver stage and build the power stage with EML 300B and KR 300BLX (15W bass only) leftowers from better times.

I don't quite understand what you do but if you are on budget and would like to "spill a little blood" then why you are tiring to build 3 channels of Melquiades? First of all the line lever crossovering might be quite complex. Second, what if it turns out that I am full of shit and Melquiades does not sound good? Would it be easer to build one properly operating Milq and then, if you understand and upreciate the result, to propagate the same sound across 3 channel? It is what I would do if I were you.

The caT

AnonymousUser wrote:

Line level crossing or passive speaker level crossovers-same devil.

If you are planning to build a dedicated LF SET then the line level crossing vs. passive speaker level crossovers is not the same devil. With any seriously performing LF section any cap, indictor or resistor you put in the game after the transformer will very severally screw up dumping of the drivers and essentially the quality of bass. If you go line level then be advised that Melquiades is no-feedback and therefore there is not ways to put a line level filter in there without insertion lost. The 6C33C is kind of 8-10W tube and with 2-3 db of insertion lost you would need a fairly sensitive drivers, or preferably an array of the driver is you use horns.  To make it all properly it would not be cheap and easy solution.

Anyhow, if you build a dedicated LF Melquiades then if you wish I might sell you a pair of my leftover transformers. It is 6C33C against 8ohm, 1:8, 450mA gap, ~15H primary and I believe 23R DCR of secondary. The transformer at 220V/170mA on plate push full power down to 7.5Hz and roles off atop at ~900Hz. It is quite big and heavy to ship and it will be $400 per pair + shipping. I do not need this transformer as I have the identical against 5Ohm that is more precise match for my woofer towers.

Rgs,
Romy

W,

Be careful with Milq’s LF channel. When you go for a dedicated LF SET and make the SET to operate very low then you need very precisely dial in the loading of your out tube with the behavior of your LF drivers/enclosure. Without know the very specific loading demands I would not suggest you to commit yourself to buy my transformer or to order a transformer form you local winder. The LF SET is not a full range amp and the result will vary much much more then with a MF channel.

Actually, to be honest, I do not feel that you ever need a LF DSET (dedicated SET). Since you use Klipshorn bass bins and if you make the LF Milq with a transformer >7-8H then you will overload the Klipshorn LF. What is the purpose to build a LF DSET and then roll of the LF with a high pass filter. So, if you wish to built a Melequiades then get yours a regular full range Melequiades and it will be much better then forcing a poor Klipshorn to reproduce the LF the they even theoretically can’t handle and that screw up the Klipshorn’s upperbass.

Rgs,
The Cat