[maverickronin]

I keep managing to break things.  This time its one of those tiny red LEDs.  Its the right way around but it won't light up.  My DMM's continuity mode will make the first one light up a little, but the second one stays dark, both ways.  Does it have any special specifications or is it just a 1.2V red LED?  Would I have to replace the one that works with an identical one as well?

 

[Nebby]

I'd say give Bottlehead a call, they probably chose the led's for reason and I hear they're pretty good about sending out replacement parts. The typical forward voltage for the HLMP-6000 series is 1.6V and if you were to swap in a different led you would indeed need to swap out the other one as well.

 

[Beefy]

Changing the LED for something different is a bad idea. The Vf of the LED sets the operating point of the 12AU7, and I believe that the resulting plate voltage of the 12AU7 sets the operating voltage of the 6080, so a slight change might have significant negative effects.
 
Also, even if you can match the Vf, the dynamic impedance might be different.
 
Take home message...... contact Bottlehead and ask for a replacement.

 

[larcenasb]

Has anyone heard the Bottlehead with AKG K601s?
 
I had a vintage Marantz receiver that gave my K601s a warm, tubey sound that was also powerful -- I fell in love with the combo but the receiver broke. Will the Bottlehead give a similar sound (smooth and powerful) or do receivers handle headphones better 'cause of their power?
 
Thanks in advance.

 

[WyldRage]

Quote:

Has anyone heard the Bottlehead with AKG K601s?
 
I had a vintage Marantz receiver that gave my K601s a warm, tubey sound that was also powerful -- I fell in love with the combo but the receiver broke. Will the Bottlehead give a similar sound (smooth and powerful) or do receivers handle headphones better 'cause of their power?
 
Thanks in advance.

I have both and I just tried it with 3 different tubes. With the NOS 5963 in the kit, I find that the sound is bright, with a subdued bass that lacks definition. With a Electro-Harmonix 12BH7, the sound is more neutral, but lacks extension on both sides, especially the bass. With a EH 12AU7, the amp sounds better: it's still bright, but the bass is present and well-defined, if a bit lacking for my tastes.
 
In any case, the Crack has no problem driving them.

 

[tdogzthmn]

In any case, the Crack has no problem driving them.

How's the detail and bass extension on the K601? I sometimes miss mine.

 

[Doc B.]

Quote:

I'd say give Bottlehead a call, they probably chose the led's for reason and I hear they're pretty good about sending out replacement parts. The typical forward voltage for the HLMP-6000 series is 1.6V and if you were to swap in a different led you would indeed need to swap out the other one as well.

Yeah, you really want to stick with the HLMP-6000 (V drop is actually 1.56V). We are in Chicago until next Wednesday (doing a presentation for the Chicago Audio Society on Sunday). Give us a call or email next week and we will be happy to send out a replacement LED.

 

[ironbut]

Quote:

Has anyone heard the Bottlehead with AKG K601s?
 
I had a vintage Marantz receiver that gave my K601s a warm, tubey sound that was also powerful -- I fell in love with the combo but the receiver broke. Will the Bottlehead give a similar sound (smooth and powerful) or do receivers handle headphones better 'cause of their power?
 
Thanks in advance.

The Crack responds very well to tube rolling. I would venture to guess that with the right tube combo, you should be able to tailor the sound just about any way you want (there are limits of course). If you like a warmish sound, you'd be better off listening to the stock amp and skip the Speedball upgrade until you've got a good handle on the way it sounds without it.
I've found that all the Bottlehead gear that I've heard have fantastic bass. If that's what you mean by powerful, you'll probably love the Crack.
 

 

[larcenasb]

Thank you very much for responding WyldRage and ironbut -- I'll post my comments about the K601 + Crack combo once I get it. Cheers.

 

[Mak333]

Quote:

Thank you very much for responding WyldRage and ironbut -- I'll post my comments about the K601 + Crack combo once I get it. Cheers.

I'm also interested to see how the BottleHead Crack sounds with my newly acquired HD600s.  I just ordered the amp today so hopefully we are pushing the limits for the order quantity

  I'm very new to serious audio equipment and I think the HD600s straight from an X-Fi sound card sound amazing - Lack of bass ofcourse, but everything else sounds great.  I wonder how much this amp will enhance my listening experience.

 

[thewolf1976]

Have any of you added an input to the Crack? I need two inputs, rather not have to unplug the rca cables. Can anyone recommend a switch, or do you know what kind of switch Bottlehead uses for their other amps? Also the rca inputs they use? I sent an email, but I think they are out of the office this week.
 
I ordered my Crack back on the 11th, maybe next shipment!

 

[tdogzthmn]

The crack only has a spot on the panel for one pair of RCA inputs to be installed.  If you wanted to have multiple inputs I would suggest buying a separate device.  I dont know of any off the top of my head but I am sure you can find one.  

 

[thewolf1976]

I thought about building a switch box, but the cost gets a little high with the rca's and the extra cables.
 
Looks like there is enough room to add a pair of rca's and the switch knob. What do you think?
 
Hopefully bottlehead will get back to me. I was hoping to use the parts they use in their multi input amps, but I'll do whatever.

 

[Doc B.]

Hi guys,
 
Yes, we were out of town and just getting back to it this morning. It will take a couple of days to get through all of our correspondence. In the meantime - the input selector toggle switch setup of our Quickie amp could be used. Or you could just buy a DPDT toggle and a couple of RCAs from Radio Shack. You just connect the signal + from the right channel jacks to one pole and the + of the left channel jacks to the other pole. Then route the signal from the switch to the volume pot.

 

[thewolf1976]

Doc,
 
Thanks for the reply. That is what I was thinking, use the switch from the quickie. I emailed queen for the specifics. I wanted to use the same materials, knobs, rca to match the Crack. Just aesthetics.