High ouput source for my EMP

[AdamZuf]

Quote:

Originally posted by AdamZuf which should i use for my EMP?

well.. let's say i might use the DAC for something else...so change that question to : "which should i use for normal line-level?"
i don't want to meet "mr. clipping" in another place

(that in a case which the max input line level for the EMP is higher then normal line level)

 

[Hirsch]

First, find out if you need to change anything. As long as the volume pot on the EMP is in front of active circuitry, all you have to do is use small motions of the volume control and all will be well.

There is a set of 12 resistors that need to be changed. Try the diomods yahoogroup. There's a spreadsheet in the Files area that allows you to calculate the resistor values for any gain that you want.

 

[AdamZuf]

sorry for knowing crap about how amps work, but i thought the volume pot is after the active circuitry, because i can see no change in the tubes' lighting when volume is off too.

would be nice to have a little explanation on how the EMP works (and how does the tube thing goes exactly)

ah wait...the tubes are'nt active circutry?

 

[AdamZuf]

Quote:

Originally posted by Tomcat This seems to be a great tube: http://www.thetubestore.com/nos-6085.html

do you think it's a sure shot for 60$?

 

[AdamZuf]

Quote:

Originally posted by Tomcat I have tried the 12AU7-substituted EMP with high-impedance, low efficiency phones now. My Beyer 770 Pro is rated at 250 Ohms and 96dB/mW. It's not a good combination. The EMP seems seriously underpowered with the Beyer. I guess if one wants to try the EMP with the 12AU7 and reduced power and reduced voltage swing, a high-efficiency and low-impedance headphone is mandatory.

Tomcat, this is a quote from another thread.
did you try the beyers with an E80CC tube?

 

[AdamZuf]

this is a"E80CC " search in ebay:

these hang around 7.5 mA:
http://cgi.ebay.com/ws/eBayISAPI.dll...&category=3284

these hang around 11.5 mA:
http://cgi.ebay.com/ws/eBayISAPI.dll...&category=3284

and i don't know what about these:
http://cgi.ebay.com/ws/eBayISAPI.dll...category=14980

what's about the mA thing? does it affect gain?
which tubes should i get?
any considerable risk of fake tubes with these brands?

and please..leave the bidding for me

or it would be nice to share a winning bid with another head-fier!
i just need 1 or 2 tubes.. the cheaper the better for me
(to think i thought i can get away with HD600 + Porta Corda at first...he he)

as we are dealing with eBay.. fast replies are welcome

 

[Hirsch]

Quote:

Originally posted by AdamZuf sorry for knowing crap about how amps work, but i thought the volume pot is after the active circuitry, because i can see no change in the tubes' lighting when volume is off too. would be nice to have a little explanation on how the EMP works (and how does the tube thing goes exactly) ah wait...the tubes are'nt active circutry?

The tubes are active, but as long as they can handle the increased voltage from the source, there's still no problem. If the voltage is too much, you'll hear clipping from the amp. You'll know right away if you're hearing it. If it sounds like everything's working, it is working.

 

[Tomcat]

Quote:

Originally posted by AdamZuf Tomcat, this is a quote from another thread. did you try the beyers with an E80CC tube?

Adam,

The Beyer 770 Pro's bass slam has earthquake-like quality with the E80CC. It's simply scary. I can offer nothing but praise for the E80CC. It's so good, it's stunning.

 

[AdamZuf]

Hirsch, so ain't the volume pot after the tube circuitry, if they light the same in all volume modes?

and would somebody please say "go for it" for 1 of the auctions above, please?

 

[Hirsch]

Quote:

Originally posted by AdamZuf Hirsch, so ain't the volume pot after the tube circuitry, if they light the same in all volume modes?

Not necessarily. The orange light in the tubes is from the heater, which stays at constant voltage regardless of the volume setting.

 

[AdamZuf]

Quote:

Originally posted by Tomcat The Beyer 770 Pro's bass slam has earthquake-like quality with the E80CC. It's simply scary. I can offer nothing but praise for the E80CC. It's so good, it's stunning.

1.so your 770 pro (250 Ohm) are now driven well, after you switched the 12AU7 to E80CC?
2.would you say it adds a bassy quality to all headphones you tried this tube with?
3.if so, was it true for several brands of E80CC (if you had the chance to test it) ?
4.heard talks about the E80CC ain't a REAL substitude for 12AU7.
why is that?
5.i understand you're using the E80CC for quite long time with no problem. for how long is that?

 

[AdamZuf]

Hirsch,
do you know the volume pot actually works as a "gain" pot for sure, or just throwing an option?

 

[AdamZuf]

Quote:

Originally posted by pigmode The market for the 6922 class tube is a veritable snake pit filled with counterfeits and old half dead tubes. I was fortunate enough to acquire a few Holland Orange Globes from an impeccable source--Doug in Ecuador.

is there a way to tell the tube's condition with no tester?
just by looking at them...turned on/off ?
(other then if you think its sound sucks

)

 

[Hirsch]

Quote:

Originally posted by AdamZuf Hirsch, do you know the volume pot actually works as a "gain" pot for sure, or just throwing an option?

Volume refers to sound. Gain refers to electrical signal. However, an increased electrical signal normally leads to louder sound. If increasing the setting on the volume pot on your amp doesn't make the sound louder, send it back immediately

 

[AdamZuf]

you didn't get me..
can you tell for sure if the volume pot is before the active electronics (like in mixers), or is it after them (like "master volume" in mixers)
not that i compare amps to mixers!..but just to get the idea..