[astroman302]

I understand that the mkII has adjustable impedance setting, so would this make the mk's equal/better than the 1+s for driving grados?

This is my final decision, I'll be placing the order soon.

 

[DarKu]

I+ has more power for low impedance phones due to having an output transformer, MKII is an OTL design = not suitable for low impedance phones. Especially for Grados, MKI+ is better, here you can find a long thread about it, you can upgrade it actualy by changing the stock op-amp and the stock tubes

 

[Uri Cohen]

Go with the I+.

 

[rederanged]

Quote:

Originally Posted by DarKu /img/forum/go_quote.gif I+ has more power for low impedance phones due to having an output transformer, MKII is an OTL design = not suitable for low impedance phones. Especially for Grados, MKI+ is better, here you can find a long thread about it, you can upgrade it actualy by changing the stock op-amp and the stock tubes

From the eBay listings, they both appear to be OTL, but the I+ is a hybrid amp (solid state output stage), so would have been easier to design with low output impedance.

 

[DarKu]

I+ is not OTL (output transformer less) !
It's a Hybrid indeed which mean it uses op-amps (or other solid state components [discrete components]) and tubes too, go for I+ get the western electric tubes and some LM4562/OPA2604/AD826 later

 

[john57]

Quote:

Originally Posted by astroman302 /img/forum/go_quote.gif I understand that the mkII has adjustable impedance setting, so would this make the mk's equal/better than the 1+s for driving grados? This is my final decision, I'll be placing the order soon.

Both have jumpers to adjust the gain range but not for impedance setting which implies a output transformer which none of the two has. Mk11 is perfect for medium to high and there are users successfully using the mk11 with low impedance cans. The LD 1+ will have no problem driving your grados. The Mk11 is an all tube desgin design and the LD 1+ has the soild state output stage and it is what I have and very happy with it.

 

[rederanged]

Quote:

Originally Posted by DarKu /img/forum/go_quote.gif I+ is not OTL (output transformer less) ! It's a Hybrid indeed which mean it uses op-amps (or other solid state components [discrete components]) and tubes too, go for I+ get the western electric tubes and some LM4562/OPA2604/AD826 later

I'm not sure why it's incorrect to refer to something that doesn't have output transformers as Output Transformer-Less, but maybe that's a term reserved exclusively for all-tube amps, not hybrids. Regardless, it sounds like the OP is getting sound advice here, so I will cease wasting bits with my semantic gripes.

 

[bdr529]

The term can be used anywhere and all solid state amps are OTL, it just matters more for tube amps because their output impedance is high. I believe the distinction should be that an amp HAS output transformers, not that it doesn't.

The LD1+ has a solid state output i guess so it doesn't need output transformers to get a lower output impedance.