[jonathanjong]

So, I've been told that OTL amps like MkIII are generally unsuitable for low impedance cans. By all accounts, they should do well with my HD580, but my SR325i is a 32 ohm (I think) can, after all. Anyone who owns both MkIII and SR325i care to comment?

P.S.: I have another thread up for EF2 v. MkIII comparisons generally.

 

[sinisterm]

I had 325i's with LDMKIII. Worked like a charm. I suggest you to try Tung Sol's with the 325i, I loved it at least.

Actually I've only used low impedance phones with my LD. 325i, GS-1000, AD900.

Someone said something about low impedance phones causing power tubes to heat more than with high impedance phones and it could shorten the tubes lifespan, but I'd say it's nothing to worry. Have used same power tubes for months and months without problems.

 

[lescanard]

I very much enjoy the LD MKIII with my 352is'. I read that in the past as well but think that maybe that's a slight exaggeration. That being said - I have not tried my Grados with other non-OTL amps - but find the Little Dot to be very good with these cans. The M8161s are a particular favorite of mine with the Grados.

 

[jonathanjong]

lescanard: Are you using your D10 as a DAC for the MkIII?

 

[tke398]

Quote:

Originally Posted by lescanard /img/forum/go_quote.gif The M8161s are a particular favorite of mine with the Grados.

I agree with the Mullard M8161's being a great choice for this amp. I also use the amp with my Denon D7000 which is another low impedence amp and it sounds really good together. If you can tolerate the sound of the Grado 325i's, the amp won't have a problem driving them

 

[Denys]

Hi,

I also own 325 and LDIII. Originally bought the amp for my old Senn 424, I was really surprised by the sound with the Grados... Not so good with the Senn, but they are very difficult to drive. I also own an Antique Sound Lab that could be switched to be OTL or not. In both cases, the ASL is very ggod with the Senns, but not very much with the Grados.

My intention was to sell the Grado, but after I heard the match of the LDIII and the 325, I will keep them.

Lescanard mentioned the Mullard tube, I will order a pair on Ebay, cause now I have the stock tube.

End result; it's a surprisingly good match.

Denys

 

[lescanard]

Quote:

Originally Posted by jonathanjong /img/forum/go_quote.gif lescanard: Are you using your D10 as a DAC for the MkIII?

I do use the D10 as a DAC for my MKIII - I run Optical from Macbook (lossless) to D10--->LDMKIII--->Grados or k701s - fantastic combo IMO. I love the D10 as a stand alone portable option for the Grados as well - it's an amazing little unit!

 

[Stitch]

I got the MKIII when i only had the DT880's. The SR325is are working very well with it too.

Quote:

Originally Posted by sinisterm /img/forum/go_quote.gif I had 325i's with LDMKIII. Worked like a charm. I suggest you to try Tung Sol's with the 325i, I loved it at least.

x2
Got a pair of Tung-sol 6AK5, best I've heard so far.

 

[ScottieB]

Should share my experience. I use my 325is's with my MKIII. After less than a year my first set of power tubes starting sounding distorted - but ONLY with my Grados. With the Senns (300ohm) they were still fine. I contacted David from LD and he said this was normal and due to the low impedance Grados being a 'very heady load' for the OTL MKIII. He said to expect the power tubes wear out faster with low impedance cans and recommended an impedance adapter (which I had made by a DIYer here). I've been using the adapter since with no issues thus far, although it has only been a few months.

Oh by the way, the Grados sound pretty darn nice with this amp, just be aware that you're placing a somewhat tough load on the power tubes. Oh and as far as driver tubes, the GE 5-stars are my current favs.

 

[SemiAudiophile]

when i owned the LD MKIII, i had no problems with it driving the Grado's. it sounded pretty good to me as far as i know. i'd always set the gain to lowest though. an impedance adapter would probably help too. M8161 is a nice tube choice.

 

[ScottieB]

Quote:

Originally Posted by SemiAudiophile /img/forum/go_quote.gif when i owned the LD MKIII, i had no problems with it driving the Grado's. it sounded pretty good to me as far as i know. i'd always set the gain to lowest though. an impedance adapter would probably help too. M8161 is a nice tube choice.

Yeah just to clarify - it wasn't the SOUND that was affected, just the potential longevity of the power tubes.