MG Head DT CDV - Page 3

Well actually you can set it between the clicks and it holds that volume position fine.

quote:

"Well actually you can set it between the clicks and it holds that volume position fine."

Hmmmm. You're right. I never tried that before.

Mike,
Cool, the Headmaster looks nice stacked in our follow-up posts!

i am in contact with the designer.

I am in contact with the designer, Joeseph Lau. he is doing most of the stuff ASL puts out personally. This might be the reason that some of the parts are differnt. From what i gather he is operating on slim profit margins.

Next time that i talk with him i will ask him about the CDT version to see what is differnt. Just finished writing out the Mg head manual, so its more intelligent sounding.

Flashbak and mbriant - I see you both have the sugden as well as the MG Head. Can I take that to mean that you both enjoy listening to what appears to be the opposite ends of the music sound spectrum?

Well initially I had trouble adjusting to the Sugden sound or should I say lack of it compared to the MG Head DT. However, it has now totally won me over, and I've since decided to sell the Head. As mbriant would say I'm a one amp kinda man!

Yes, I'm into variety ponzio and very much enjoy both the Headmaster and MG Head. They're different amps no doubt, but both have excellent qualities. I switch between amps and headphones quite a bit, but I'd have to say the Grado 325/Sugden combo is my favourite and most listened to.

i dont know.....

[QUOTE]Originally posted by mbriant
[B]quote

"If they upgraded the volume pot (something you could do too), it probably would have an effect on sound quality"

Sure would, i doubt that there would anything worth more than $10 in there. I have put a DACT stepper into my tube preamp, and that is incredible. MY next $100 goes to putting a DACT and musicaps into the Mghead. BTW stock mine has Kimberkaps, and a ALPS 100AX2. What is interesting is that the one that i replaced in my tube preamp, was the same model and it was smooth. I think that generally all of these small carbon film pots are generally very poor interms of quality anyway, so even if there is a upgrade i dont think it could be that big a deal, unless the Iron is upgraded. I think that it was done once allready tho.

Yes, the stock pot is an Alps. It's a good pot. I doubt they could do much better with a different pot. The next real step up would be a stepped attenuator. Shunting the pot would still be a big step up from the stock pot, and shunting can be done for the price of a pair of good 47K resistors. I haven't shunted mine yet, but it's on my list of things to do. I'm evaluating the effects of my other mods first.

Even more dramatic results could be obtained from switching the coupling caps. The coupling caps in the stock unit are .22 uf REL Multicaps of the PPMFX series. It's a pretty good cap by consumer audio standards; bottom of the REL line, made of metalizied polyproplyene. They retail for about $3 each. There's still loads of room for improvement here, both in terms of cap size and cap type. It's possible one could go as high as 1.5uf without wasting money or space (better bass response). Film and foil or paper and foil would probably sound much more detailed and smoother than the stock metalized poly. I'm switching to high capacitance film and foils myself, since there's not enough room for paper and foils.

Next in order of impact would probably be the resistors. The unit comes with generic metal films. You could improve the sound a lot with replacements. I'm using Rikens in the signal path. Next round, I'll put some precision resistors in the power supply path, which shouldn't be very dramatic, but will still help some.

The pot would be the next thing to work on -- either shunt or replace with a stepped attenuator.

After that, the power supply caps are Nichicon VX -- these are standard grade stuff, and are another good target for upgrading. Also, the diodes are IN4004 - noise city; replace with something quieter.

And the layout and quality of the wiring harness makes me shudder. I STILL can't figure out why it doesn't hum like an aquarium pump.

This is before we even start talking about simple circuit mods.

Plenty of possibilities for fun here.

What's a quieter diode than the IN4004? I have a feeling I might be using those in one of my DIY amps (I'm not feeding it AC right now, but maybe in the future).

Possum, there are other fora in which I would be afraid to answer your question for fear of unleashing a holy war. Suffice it to say that diodes are like opamps -- everybody's got a favorite!

The only hard and fast rule I have is to NEVER us an IN1004 diode or other IN series diode. Too noisy.

My personal favorite for tube amps is UF4004 (or UF1004 depending on the mfnr) with a C-RR-C snubber to keep the recovery spike noise from getting sucked back into the transformer. Take two 10-ohm wirewound resistors and tie both their ends together with 0.01uf 2 kilovolt ceramic disc caps, then put the whole deal in series between the transformer secondaries and the diode bridge (one secondary wire for each resistor).

Other guys swear by the HEXFREDS. I use them for SS stuff. No snubber required.