Golden Gate DAC. Is normal to have a little mechanical hum?

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Dracule1

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #20 on: 15 Aug 2015, 01:58 am »
Rob, please check your PM.

wisnon

Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #21 on: 15 Aug 2015, 10:07 am »
Yes the 274B is compatible.

Dracule1

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #22 on: 1 Sep 2015, 07:09 am »
Update.  The hum through the speakers has pretty much been solved.  When the EML 45 tubes were shielded with the supplied tube cages and grounded properly, the hum was attenuated by ~10 dB at normal listening volume.  Seems the EML 45s are very sensitive to hum.  Now, I have to have my ear about 1 feet from the speakers to hear a slight hum at normal listening volume. It no longer is noticeable during quiet music passages.  With the tube cages in place, I think there is subtle loss of warmth in the sound, which I kind of miss.  Anyone using the tube cages with their GG? 

The slight mechanical transformer hum still exists.  It is audible from the listening position when no music is playing.  Once the air conditioner kicks in, the mechanical hum gets drowned out.  I think this is normal, but I ask if other GG owners are experiencing the same mechanical hum?

Rob recommended the TJ Fullmusic 300B SE to try with the GG.  I did a search and only found sellers in China (mostly eBay) selling these which are quite pricey at $750/pair.   Can anyone recommend a reliable sellar?  Anyone try the Elrog 300B?

Thanks!

wisnon

Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #23 on: 1 Sep 2015, 10:15 am »
Elrogs seem unreliable.

What about the Sophia eletric Carbon Princess and the Royal princess? they are much cheaper.

Did you also try Cunningham vintage 345 globes and RCA 245 globes? They have oodles of MR warmth and are fairly cheap.

Dracule1

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #24 on: 1 Sep 2015, 03:40 pm »
Hi Wisnon, thanks for your kind input.

 I've bought Sophia Electric 6sn7s and 274B rectifier tubes before.  I stopped buying from them when l I realized their tubes look like rebadged TJ Fullmusic tubes.  SE claims they are special selection tubes made just for them, but I have seen no spec sheet showing them to be any different than the standard TJ tubes.  Construction wise they look exactly the same, and the TJ Fullmusic 300b are hundreds of dollars cheaper.  The Royal Princess is going for $1200/pair, and I think the equivalent TJ tube is the 300B SE which sells for $750 on eBay.

I haven't tried the vintage tubes you mention, which can sound too warm for my taste.

I haven't seen anything online stating Elrogs are unreliable.  Is this from personal experience?
« Last Edit: 1 Sep 2015, 05:44 pm by Dracule1 »

wisnon

« Last Edit: 3 Sep 2015, 05:55 pm by wisnon »

wisnon

Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #26 on: 1 Sep 2015, 09:51 pm »
the 345 and 245 are cheap and still worth a shot. Also CX301

Hugh

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #27 on: 1 Sep 2015, 09:56 pm »
Do NOT get the big KR Audio tubes.
They are not reliable.
We had to return a few 845 tubes to The US Distributor so we know for a fact.

On the other hand, their 2A3s are very very good.

wisnon

Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #28 on: 2 Sep 2015, 08:11 am »
The 845 does NOT work in the Lampi Dac, so not an issue.

Hugh

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #29 on: 2 Sep 2015, 01:38 pm »
My bad.

You are correct.

Their 300B & 2A3 tubes are just fine.

Thanks,

The 845 does NOT work in the Lampi Dac, so not an issue.

sfox7076

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #30 on: 2 Sep 2015, 01:53 pm »
Norman,

Have you cleared the UU4 with Lampi?  It's a 4 volt rectifier, not a 5 volt.  25% over spec seems to be pushing it pretty hard.

Shawn
« Last Edit: 2 Sep 2015, 06:32 pm by sfox7076 »

wisnon

Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #31 on: 3 Sep 2015, 05:53 pm »
My bad.

You are correct.

Their 300B & 2A3 tubes are just fine.

Thanks,

Not a prob. Thanks for the info anyway…always useful.

Shawn, is the UU4 the 596? I thought the 596 was a 5v recti. On first blush, I would ONLY use a 5v recti.

Edit: Shawn my bad, i read it too fast. UU4 os 4v and I guess unsuitable. i will edit my post above...

Dracule1

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #32 on: 9 Oct 2015, 01:01 pm »
Final update.

The mechanical transformer hum issue I've been having with the GG has been solved.  As sfox7076 pointed out, there was DC on my AC line and the AVA humdinger completely removed the hum.  Interestingly, my tube amp has no mechanical hum issue at all without the humdinger.  According to my amp designer, he designs his power transformers so DC on the AC has minimal if any effect.  Thanks sfox7075!  :thumb:   

As for the hum I get through the speakers, the tube shield has helped out a lot.  The EML 45 is the most susceptible to hum.  The Psvane 101D has the least hum.  The TJ Full Music 300B SE is somewhere between the two.  My next stop is the Takatsuki 300Bs.

Thanks all for you help.

wisnon

Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #33 on: 9 Oct 2015, 02:07 pm »
I hear that the Px4 are the quietest tubes of all.

Let us know what you think of the Takats!

sfox7076

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #34 on: 9 Oct 2015, 03:00 pm »
Glad to help.  It is likely that the amp designer built something similar to the humdinger into his amp power supply.  My tube amps have something similar in them.  And, well, I have also learned some transformers are more susceptible than others.  Regardless, it is the first thing I think of when I hear there is transformer hum.  Some people argue that things like the humdinger could degrade sound, but I just cannot believe that. 

Shawn

sfox7076

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #35 on: 9 Oct 2015, 03:08 pm »
One other thing, don't bother looking for the DC source unless you really want to lose your mind...

Dracule1

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #36 on: 9 Oct 2015, 03:36 pm »
I hear that the Px4 are the quietest tubes of all.

Let us know what you think of the Takats!

So far I like the Psvane 101D and TJ 300B about equally, but for different reasons. The Psvane is more dynamic with better low end extension.  The TJ has a more relaxed sound and almost as dynamic and extended in the low bass.  The EML 45 is not as transparent, extended, and dynamic as the other two and is warmer sounding.  However, I'm using the Psvane 274B with the 101D and 300B.  I was using the EML 5U4G withe 45.  So not apples to apples comparison.  Need to try the 45 with the Psvane 274B to make final conclusion.


Dracule1

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #37 on: 9 Oct 2015, 03:59 pm »
Glad to help.  It is likely that the amp designer built something similar to the humdinger into his amp power supply.  My tube amps have something similar in them.  And, well, I have also learned some transformers are more susceptible than others.  Regardless, it is the first thing I think of when I hear there is transformer hum.  Some people argue that things like the humdinger could degrade sound, but I just cannot believe that. 

Shawn

My amp designer said he doesn't use anything like the humdinger in his amp design.  According to him, it's all how the power transformer itself is designed to be less susceptible if not immune to mechanical hum. He designs his own power and output transformers.

When I first used the humdinger, I used a familiar power cord from the AC outlet to the humdinger. I didn't like what the PC was doing to the sound. It actually made the sound more thin and anemic.  So I bought an adapter that plugs the humdinger directly into the AC outlet.  Now, I get the sound I was used to without the mechanical hum. I don't think the humdinger itself degrade the the sound, more likely the PC they're using to connect the humdinger to the AC outlet.

sfox7076

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Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #38 on: 9 Oct 2015, 06:11 pm »
OK. 

wisnon

Re: Golden Gate DAC. Is normal to have a little mechanical hum?
« Reply #39 on: 9 Oct 2015, 06:20 pm »
So far I like the Psvane 101D and TJ 300B about equally, but for different reasons. The Psvane is more dynamic with better low end extension.  The TJ has a more relaxed sound and almost as dynamic and extended in the low bass.  The EML 45 is not as transparent, extended, and dynamic as the other two and is warmer sounding.  However, I'm using the Psvane 274B with the 101D and 300B.  I was using the EML 5U4G withe 45.  So not apples to apples comparison.  Need to try the 45 with the Psvane 274B to make final conclusion.

EML 45 mesh is better and more expensive than the solid plate version.