2. amps-preamps
  3. 192696-139155

Your journey with lower-watt tube amps -- Can a kit be good enough?

Looking for stories about your low-watt amp journeys.

Here's the situation: I have new speakers, 97 db. Trying them with lower watt tube amps (45/211, 300b, etc) seems generally wise. I am attempting to borrow some from audiophiles in the area. 

The horizon beyond trying these things involves actually buying some. I'm looking at a budget limit of about $5k.

Curious as to folks' experience with lower-watt amp kits vs. those of good makers (e.g. Dennis Had, etc.).

If you have any thoughts about the following, I'd be interested:

Did you start out with a kit and then get dissatisfied? Why?

Did you compare kits vs. pre-made and find big differences?

Did you find you could get the equivalent level of quality in a kit for much less than the same pre-made version? How about kit vs. used?

Also: did you find there was a difference between "point to point wiring" vs. "PCB" in these various permutations?

I realize that there are good kits and bad ones, good pre-made amps and bad ones. I'm hoping you'll be comparing units which seem at comparable levels of quality and price-points.

Thanks.

128x128hilde45
atmasphere's avatar
atmasphere
11,938 posts
 

@bruce19  You could install a coupling capacitor between the source (perhaps a preamp) and the SET, with a value calculated to have a -3dB point at the desired crossover frequency.

Frequency in Hz = 1,000,000/Capacitance in uF times Resistance on Ohm time 2Pi  (Usually when this formula is used the one million is a 1, but the capacitance is in Farads, which is too large to be easy to use. So I do the formula this way so I get practical audio values)

So if you wanted 60Hz as the crossover frequency and the input impedance of your amp is 100KOhms, then the capacitor would be about 0.027uf (that yields a 59Hz -3dB point).

This cap can be tiny since it does not need to handle much Voltage. So you might be able to install it inside an RCA connector of the interconnect cable.

devinplombier
289 posts
 

@bruce19 

If you already own the 2x4, there's no harm experimenting with an active crossover setup like you described, which sounds like it would work fine. If you're pleased with the proof of concept, then you can consider the DAC question. Just my 2¢! 🙂

Ag insider logo xs@2x
bruce19
275 posts
 

That is great, thank you! I needed that specificity of detail in your example to get it. I'm looking forward to giving this a try. Probably as good a jump in performance as a $1,000 cable :-)

 

Ag insider logo xs@2x
bruce19
275 posts
 

@atmasphere 

PS to the previous reply. Does the type pf cap matter? Film or ceramic? I don't think electrolytics come in that small a rating.

atmasphere's avatar
atmasphere
11,938 posts
 

@bruce19 There's a kind of ceramic cap called an 'NP0' (for Negative Positive Zero) which can sound surprisingly good. They are available with leads and in the value you need, are about the size of a small bead. By ceramic cap standards they are expensive, costing a few dollars each. You might look into them; we've compared them to a number of high end coupling caps and heard no difference. I don't think they are available in values above about 0.1uf. But they are available in Voltages as high as 630V. You only need 50v though so the part will be tiny. Here's a link from DigiKey:

https://www.digikey.com/en/products/detail/murata-electronics/RDE5C1H273J2M1H03A/10703951

More to discover