[srserl]

The lightspeed, as is, does not attenuate a balanced signal, so you would need 2. I have ideas to try with respect to a balanced ldr attenuator based on the lightspeed, but have only built an unbalanced one on perfboard. I plan to later put it in a Pass Labs B1 buffer preamp.
For a lot more info on the Lightspeed and buying matched sets of ldrs, see the thread on DIYAudio.com.

 

[minivan]

a local is generous enough to give me a commerical version of kgss from headamp for a week to compare with the exstata.

setup for comparison is:

buffalo dac balance out to exstata
buffalo dac single end out to kgss
(did comparison first between buffalo balance/single end out to kgss to make sure there's not difference between the two)
headphone is o2.

listen to one track first on one amp, switch over to the other amp, repeat the the track.


one most obvious different when switching over from kgss to exstata is: exstata little better resolution. imaging is crisper, sharper, better focus, better defined.

soundstage is a bit wider with the exstata, there 's a bit more space
between instruments.

kgss sound warmer, laid back, exstata has faster attack and transient response.

vocal is more forward in kgss, vocal in exstata sound a rew row further back but without lost of detail and focus.

can't tell much different on bass between the two, may be bass in exstata is a bit leaner and tigher with better texture and definiton.

treble has better extension on the exstata, revelation of micro detail in this area is better.


i like to say thanks again to the indiviual who let me borrow his kgss for a week.when i first built the exstata i thought it's very good, but have no idea how good it is in compare to other well known electrostatic amp ( the only full size eletrostatia amp i had heard at the time is the little known chinese diy 8ps amp mr he built for me)
the kgss enbale me to set a benchmark and compare the exstata with.

i am extremely happy with my exstata, it only cost me $450 aud all up ( about $400 usd at the time of currency exchange), a Significance saving. thanks alex for bringing us this amp.


some obseration of the kgss, it run very hot, i can feel the heat on my hand through the vent on the case. dc offset is over 8v on startup and it take over 20 minutes for the dc offset to drop below 1v.

 

[les_garten]

You might want to edit your post as to which exstata you compared?

EDIT: Solved with the pic added!

 

[fierce_freak]

Nice impressions, minivan.

I managed to get my eXStata power supply up and running the other night, so the rest shouldn't be too far behind. I've been super busy with house renovations and certification studying leaving electronics on the back burner.

 

[fierce_freak]

double post O.O

 

[audionut]

some obseration of the kgss, it run very hot, i can feel the heat on my hand through the vent on the case. dc offset is over 8v on startup and it take over 20 minutes for the dc offset to drop below 1v.
__________________
Yes, my P2P KGSS runs very hot as well, and I had a hard time getting enough heatsinking to cope with the heat. Also, my offset takes at least 20 minutes to drop below 1V too. I recently had a Blue Hawaii to repair for another headfier, and the offsets also took forever to stabilize. Not sure why this is. On my eXStata hybrid, offsets go below 1v within a few seconds after power up, if I remember right.
I have not been able to post any impressions between my KGSS and eXStata, due to my KGSS being down for repair (resistor opened up in output stage), and my ESP950's having to go to Koss for lifetime warranyt repair. Hopefully get some impressions soon, as my phones are back and the KGSS is up and running again.

 

[pabbi1]

Hopefully a few more of you guys are getting closer... sitting here listening to The Verve Pipe "Villains"... just feel guilty, like 'flying private' on a Gulfstream - sure more people could come along, but somehow, only a couple could make it.

Now to dump this crappy source, and get my new tube output stage source in by next weekend, then we'll really see what's what. One of these days, I'll get around to tube rolling - CBS black plates (that I have in now) vs Tung Sol vs Amperex vs Telefunken, so, yes, I am still acquiring tubes, because this ain't my only electrostatic amp that uses 6s4a.

 

[WilCox]

Quote:

Originally Posted by pabbi1 /img/forum/go_quote.gif Hopefully a few more of you guys are getting closer...

I should be joining you in your Gulfsteam soon.

My backordered parts from Mouser arrived this week and I now have completed PS and amp boards for my SS eXStatA. My Hammond case is here and a four-gang Alps is on the way thanks to Nate. Hope to find time in the next few days to get her up and running.

 

[pabbi1]

I am REALLY curious if you SS guys like yours as much as I am the hybrid.

 

[Keithpgdrb]

sure would like to see some more pics of the builds I'm reading about.. I need case ideas for the future.

 

[Lou Erickson]

I am finally getting all the last parts together to build this.

I think the last stumper for me is a volume pot. I'd really prefer a four-gang pot or stepped attenuator, but am not finding anything I'm thrilled by. Suggestions would be welcome for something reliable and not too expensive.

I've also noticed a quirk with a couple of things on the power supply BOM. I got the part numbers listed, but the wattages of a couple of the resistors are lower. For instance the part number for R9-R12 is listed as 71-CCF55-150K, for 1/2W 150Kohm resistors. The parts I have have the same part number, and are 150Kohm, but are only 1/4 watt. The order detail says "Metal Film Resistors 1/4watt 150Kohms 1%
Rated to 1/2watt".

Similar situation with R17, R18, R20, R21. BOM says 1/2 watt, part from Mouser says 1/4 watt, but the order detail says "1/4watt... Rated to 1/2watt".

Are these the right ones, or should I order higher wattage? (My instinct is to order larger.)

So far, so good... =)

 

[runeight]

Hey boys. I have a few early morning minutes to check in on you. I've tried to read the last several pages.

There was one comment by one of you about how the amp likes to oscillate. I don't remember who this was but please see the website about grounding the heatsinks. This will stop the oscillation.

One of you lives in Italy (Trieste), but I don't remember who you are. My wife emailed me saying that the package has been returned. I don't know why and won't know until I return home. My apologies for this as I might have messed up the address. Please email me and when I return I'll send the boards again.

Resistors in the PS are ok. CCF55 can handle the wattage requirements for the intended use.

Have I missed anything important? If not, thanks for all of the nice reviews/comments. I'll go back to other business, which at the moment is in Wash, DC where we are having a blizzard with at least 15" of snow on the ground with another foot at least to come. I just want to go back to Texas where the skies are bright and I can see from horizon to horizon.

 

[digger945]

Quote:

Originally Posted by Lou Erickson /img/forum/go_quote.gif I've also noticed a quirk with a couple of things on the power supply BOM. I got the part numbers listed, but the wattages of a couple of the resistors are lower. For instance the part number for R9-R12 is listed as 71-CCF55-150K, for 1/2W 150Kohm resistors. The parts I have have the same part number, and are 150Kohm, but are only 1/4 watt. The order detail says "Metal Film Resistors 1/4watt 150Kohms 1% Rated to 1/2watt". Similar situation with R17, R18, R20, R21. BOM says 1/2 watt, part from Mouser says 1/4 watt, but the order detail says "1/4watt... Rated to 1/2watt". Are these the right ones, or should I order higher wattage? (My instinct is to order larger.) So far, so good... =)

I'm not sure you have the right parts per the BOM as I have not had time to look at it lately, but the Vishay Dale CCF resistor, according to the data sheet, is dual rated. If you look at the first bullet under "Features" at the top of the data sheet, it gives % stability at a given wattage rating. Ultimately they are rated for ½ watt at ≤250V. The CCF60 is rated up to 1 watt and ≤ 500V (see "Technical Specifications" on both data sheets).
On a similar note, if you look at the data sheets for RN and CMF series resistors, you will see remarks that they are exactly the same part. The only difference is the rating and the markings, with military RN series parts being rated lower than the equivalent CMF part.

Resistors, fixed discrete - Vishay

EDIT: Also note Alex's remarks above.

 

[bgcgreality]

Недвижимость в Болгарии очень прибыльное и выгодное вложение, для покупателя. Приобретая недвижимость в Болгарии Вы надежно вкладываете свои денежные средства и, кроме того, получаете квартиру или дом на берегу моря. Для граждан России покупка квартиры в Болгарии проблем не составляет. Вид на жительство получает каждый, кто открывает бизнес или приобретает недвижимость в Болгарии. Недвижимость в Болгарии обойдется Вам намного дешевле, чем в России на Черноморском побережье. цена недвижимость болгария

 

[marcus1]

Hi Alex

I posted a query a few days ago about using the Lightspeed Attenuator with the eXStata (hybrid) but didn't get an answer. The criteria for using it are:

1: Low source impedence (cd player) <50ohms
2: High input impedence (amplifier) > 50k.

What is the eXStata input impedence?

Thanks

Quote:

Originally Posted by runeight /img/forum/go_quote.gif Hey boys. I have a few early morning minutes to check in on you. I've tried to read the last several pages. There was one comment by one of you about how the amp likes to oscillate. I don't remember who this was but please see the website about grounding the heatsinks. This will stop the oscillation. One of you lives in Italy (Trieste), but I don't remember who you are. My wife emailed me saying that the package has been returned. I don't know why and won't know until I return home. My apologies for this as I might have messed up the address. Please email me and when I return I'll send the boards again. Resistors in the PS are ok. CCF55 can handle the wattage requirements for the intended use. Have I missed anything important? If not, thanks for all of the nice reviews/comments. I'll go back to other business, which at the moment is in Wash, DC where we are having a blizzard with at least 15" of snow on the ground with another foot at least to come. I just want to go back to Texas where the skies are bright and I can see from horizon to horizon.