Magnavox 150aa Monoblocks - best set up

[Ntc76]

Oh boy, this question. Put on your flame suit

Honestly I use a lot of basic yellow caps for coupling. The Illinois ones are perfectly serviceable and they're cheap. 716P orange drops also aren't stupid expensive, and from memory there just aren't a whole lot of parts in these. Probably what, 10 caps plus the electrolytics per unit? For electrolytics it ends up being any of the big names from Mouser or Digikey. I'm not super picky, it just has to be from some company someone has heard of, not One Hung Lo capacitor company.

Lol ok ok I don't know why I bought that stuff. Impatience I guess. Thanks for your input, I will get the quality parts.

 

[steve...]

Will that make the sensitivity of the two amp sections considerably different? If so, how are you planning to deal with that?

I am leaving one unchanged so I can compare them and decide which circuit I like. Then I will make the same changes or not to both amps. Does that answer the question you posed?

 

[GordonW]

If you change the sensitivity of the SE section but not the PP section, it may be difficult to get the tweeter level to match the woofer level. Especially if the tweeter amp winds up with less gain than original.

Regards,
Gordon.

 

[gadget73]

Right, thats what I was getting at. The input sensitivity on each section needs to be reasonably close to stock values, at least in relation to each other.

 

[steve...]

Right, thats what I was getting at. The input sensitivity on each section needs to be reasonably close to stock values, at least in relation to each other.

The magnavox biamp amps all have potentiometer gain controls on the high frequency amp. It is essential for this type of biamp use. In the case of the amp150 it is a 50k pot at the input to the se driver stage.

In my "workshop" I am currently running an amp-182 with the LF amp connected to a Klipsch MTM speaker and the HF amp connected to an ESS AMT. The AMT is about 5db more efficient than the Klipsch. By adjusting the HF gain pot and adding some boost to the low end (a lot below 100hz) the response is flat within a few db past the upper frequency limit of my test equipment.

 

[BillWojo]

If bi-amping, I would look at the woofer and tweeters sensitivity levels before changing gain's in the amp.
With a 1200Hz crossover it sounds ideal for a set of Altec's with the 811 horns and 416 woofers.

BillWojo

 

[glue_ru]

I found almost every cap I needed either from Austria, Japan, or good ole China....

"China" makes both good and no-so-good caps. The trick is finding good ones that aren't knock-offs. For the quality ones, you pay nearly as much anyways.
Some yellow poly's work fine, the filters, electrolytics, you want quality there, not motor-start grade caps.