quickie with low impedance phones

[pushbroom]

Is there a transformer others have used to power low-z cans? I'm new to the diy audio scene but plan to use my quickie in the studio where akg k240 55ohm cans are standard

 

[Paul Birkeland]

Generally speaking, the greater step-down ratio to power such headphones will diminish the output power of the Quickie to the point where it is no longer very useful as a headphone amp.

If you can find a pair of AKG K-240M's instead of the other K-240 models, you'll get decent output from the converted Quickie, but the design was never intended to be a studio grade headphone amp (the SEX amp or the Mainline would perform far better).

-PB

 

[pushbroom]

Thanks, I assumed that would be the case but I'm no electrical engineer...a crack or sex kit will be my next purchase but I was hoping to make due for the time being.  Guess it's time for some high-z cans :-D

 

[xcortes]

I used a Quickie with great success with Sony MDR R10s and a 50 ohm tap in an output transformer. These are THE headphones so don't be shy and try.

 

[Wanderer]

.............If you can find a pair of AKG K-240M's instead of the other K-240 models, you'll get decent output from the converted Quickie,.......

I use the AKG 240M 'phones with a Quickie. I find I really needed the choke mods or the PJCCS to get enough gain.
I prefer the sound with PJCCS over the chokes.  Also I am using the 1 k tap on the Speco transformers for the 240M.  I use the 500 k tap with some 120 ohm Yamaha YHD-1 'phones. 

With the Speco transformers  there is bass roll off starting at 60 hz with pretty much no output below 40 hz.  I did not "measure" this but this is my estimate from listening to a Stereophile warble tone test CD.

 

[pushbroom]

Thanks, I purchased the pjccs with the quickie so I should be set there.  Anyone have a transformer brand that they prefer?

 

[xcortes]

THE quintessential headphone transformers (autoformers) are Magnequest TL 404s. Mike said we wanted to do another build but i wouldn't hold my breath. They appear from time to time on the secondary market (that's how I amazed four pairs!).