I Never Get Lost, Because Everybody Tells Me Where To Go....
60 feet speaker cables is considered as long, so it is likely better to run coax cables for line level signal to your amplifiers located nearer to the speakers.
10 pair telephone wire is 10 twisted pairs of thin solid core wire in a buff coloured sheath.
It is cheap and is available from electrical wholesalers and makes very good speaker wire.
Eric.
JordanG said:
60 feet speaker cables is considered as long, so it is likely better to run coax cables for line level signal to your amplifiers located nearer to the speakers.
10 pair telephone wire is 10 twisted pairs of thin solid core wire in a buff coloured sheath.
It is cheap and is available from electrical wholesalers and makes very good speaker wire.
Eric.
Jordan finished his first gainclone, his first amplifier. He used higher quality components then I did, Auricaps and Riken resistors.
My 2 channel is basically done, and we will run comparisons over mine with Allen Bradley resistors and Solen input caps. Besides these 2 components, the only difference is the heatsinks.
first picture of Jordan, after discovering that it works:
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Brian
My 2 channel is basically done, and we will run comparisons over mine with Allen Bradley resistors and Solen input caps. Besides these 2 components, the only difference is the heatsinks.
first picture of Jordan, after discovering that it works:
--
Brian
Attachments
Peter Daniel said:
We tried bypassing the solen caps, and the dc offset didn't seem to change at all. I didn't have time to do much listening, but after 5 minutes of switching back and forth several times, it does seem to see less harsh with the caps bypassed.
Is there any disadvantage to removing the caps? One funny thing, for the bypass, we initially used a 3ft long banana plug wire with alligator clips, and when you hooked up one side, there was a quite audible radio signal playing on the speakers. With both wires connected, there was a barely audible signal. By changing it to a 1.5" bypass cable with alligator clips, the radio signal was gone when both sides were connected, bypassing the input cap. I don't know what kind of radio signal. It was advertising for Hair club for men. I would assume that it was AM radio or something.
Thanks for the suggestion. I definately will do more playing around with the gainclone for parts. I have some dale rn55 resistors that I will try next for the feedback resistor. I also want to try skinning my caps, once I get used to the sound, and see what difference it provides. The commercial product has naked caps.
Wouldn't 12k and 270k for the two resistor values give basically the same gain?
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Brian
Removing parts
Peter,
Let me understand a bit more on what you did.
Did you try inverted and non-inverted gainclones? Which did you pick?
The cap you're talking about is the input cap in which version? As you say "big caps" I'm assuming it was more than one.
In the gainclone site there's a suggestion for eliminating several parts (inverted version), like input cap and output series resistor, also zeroing DC offset using a trimpot from + input to ground. Did you try that?
There are also some reports (going with input cap elimination) of simply grounding the + input, with listening improvements. But I'm afraid that should increase offset.
In the end though, how do you guard yourself from a DC voltage that might damage your speakers?
Carlos
Peter Daniel said:
Peter,
Let me understand a bit more on what you did.
Did you try inverted and non-inverted gainclones? Which did you pick?
The cap you're talking about is the input cap in which version? As you say "big caps" I'm assuming it was more than one.
In the gainclone site there's a suggestion for eliminating several parts (inverted version), like input cap and output series resistor, also zeroing DC offset using a trimpot from + input to ground. Did you try that?
There are also some reports (going with input cap elimination) of simply grounding the + input, with listening improvements. But I'm afraid that should increase offset.
In the end though, how do you guard yourself from a DC voltage that might damage your speakers?
Carlos
None of my amps was ever guarded against DC, I just take my chances.
I used inverted version with most parts gone, so I'm using only 2 resistors (10k for series input and 220k for feedback). Positive input is connected directly to the ground with 20mV of DC. 100k pot at the input.
By big caps I meant 2 x 1.5u from Hovland. Normally I would be using 4.7u N BG but I wanted to try film caps. My amp is shown at the thread's beginning. Because it was an open concept without much shielding the big caps were prone to picking up all sort of noise.
I used inverted version with most parts gone, so I'm using only 2 resistors (10k for series input and 220k for feedback). Positive input is connected directly to the ground with 20mV of DC. 100k pot at the input.
By big caps I meant 2 x 1.5u from Hovland. Normally I would be using 4.7u N BG but I wanted to try film caps. My amp is shown at the thread's beginning. Because it was an open concept without much shielding the big caps were prone to picking up all sort of noise.
UrSv said:
They are not that bad and Dynaudio is using them in their top of the line speakers. But they are not totally transparent and musical, when comparing to the more exotic brands. It may appear that you don't need a cap at all (depending on your front end. In my system I have 20 mV at lowest volume setting and close to 100mV at maximum.
Hi,
Yes for the Solen/SRC MKP's. They suffer from excessive levels of microphonics and self induced mecrophinics. Sweep the with a high level sine wave and they sing like canaries. The often badly regarded Wima MKP10 Types (red box caps) are much better in this respect. On the other hand the Tinfoil cap's from SCR are very good.
Sayonara
Yes for the Solen/SRC MKP's. They suffer from excessive levels of microphonics and self induced mecrophinics. Sweep the with a high level sine wave and they sing like canaries. The often badly regarded Wima MKP10 Types (red box caps) are much better in this respect. On the other hand the Tinfoil cap's from SCR are very good.
Sayonara
I fired my gainclone up this weekend. I used a combination of the Thor design and Peter's "minimized" clone. I figure I'll start with the safest, most stable design and toss out parts as I pare it down. It is still in the dead bug "open" stage, dead quiet at full volume with no input except when I touch one of the pots i get a faint hum through that speaker. My shop is full of flourescent ights but they don't seem to affect the amp.
Dave (planet10), I used two (bought four) of those ApexJr 18-0-18 xformers you mentioned before and they work well but are definitely underpowered if you plan on powering some descent sized speakers. The amp will fill the room well but won't rock the house. Perfect for a couple of amps for my kids with bookshelf speakers, if you know what I mean.
Dave (planet10), I used two (bought four) of those ApexJr 18-0-18 xformers you mentioned before and they work well but are definitely underpowered if you plan on powering some descent sized speakers. The amp will fill the room well but won't rock the house. Perfect for a couple of amps for my kids with bookshelf speakers, if you know what I mean.
Kuei Yang Wang said:
Hi, KYW!
How much of that micropohonics is caused by the cap body or the wires? Can't you damp them reasonably well by gluing them somewhere? Or using some sort of strapping? If it works with tubes it should work with caps.
The only problem with Wima MKPs is they don't come in big sizes, but should be perfect for the gainclone's 2.2uF. In fact, for that low value it should pay off trying better caps.
On the other hand, as long as the canaries are in tune there's not much harm...
Carlos
Haven't tried any variations yet. Tonight, I am going to try replacing the FB resistor with a smaller value precision metal film resistors that I have on hand. I think I won't run into trouble to quickly because of the low power xformer I am using. I figure I am only getting about 20 watts/chan in its current configuration. I think this could actually hinder my finding a happy medium as the variations will probably have less affect on the sound than a higher power amp. My source is a portable CD player with a line out jack, which probably eliminates another possible ground loop problem. Once I am a little happier with the configuration I'll try it with a grounded source.
I believe it is primarily a question of the tension of the film when winding the capacitor. The equally "naked" Ansar Cap's do not "sing" under identical conditions. I find that few "naked" film cap's sound good. If they do they tend to be Foil/Film construction and fairly heavy.
I have experimented somewhat with encasing such capacitors but tend to now prefer wherever possible silver/mica, which are as close to monolithic cap's as it gets. For larger values bypass them with a suitable Film Cap, preferably a low microphonic type.
As for solid state gear, if I need a coupling cap, I find that polycarbonate types match the sound better than Polytpropylene and I tend to also prefer Mylar Cap's to Polypropylene there, though they loose some clarity. n any of the applications I cared to compare I found no comparison between Black gate and good, plastic encapsulated Mylars, the mylars wipe the floor with the BG's, but that just me and obviously as all sorts of people tell me - I ain't never yet heard a BG cap well, or I'd have liked them... ;-)
Sayonara
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