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Power Amp match for Pre amped LD MKIII / LD MK IVSE - Recommendations anybody??

post #1 of 7
Thread Starter 

Hi All,

 

I’ve tried to find some answers to this query and all I find myself doing is going through 100’s of pages of tube rolling!!!

 

I need some definitive answers – LD MKIII/ LD MKIV as a pre amp – anybody using either as a pre amp??

 

How good is the pre amp? Is it articulate? I know the obvious thing most people say is that it gives you a warmer tubier sound but that doesn’t mean much to me - i need to know finer details.

 

IMHO, I’d rather know what’s lacking rather than what it gives so I understand what to look for when upgrading.  Also how does the MKIII/MKIVSE compare to other solid state preamps that cost around $450/ £300???

 

 

So...I’m looking for a power amp –

 

I want to match the price of the power amp accordingly so I’ve set myself a budget of $450 /£300 . This would mean my future upgrade to a MKIV SE would benefit from its use also.

 

The power amps I have decided to look into are the following:

 

Cyrus 6 power – used £300-£400

Quad 99 Power – Actually £600 just seen it for £350

http://www.lintone.co.uk/special-offers/quad-99-stereo-power-amplifier-silver-1645-148-2782.php

 

Exposure 2010s2 power amp - £375

Myriad z106 - £360

 

Can anybody tell me if they have experience in using a similar set up or if there are any other potential power amps in this price range that match well with the LD’s??

I don’t mind used ones, so if anybody knows any bargains they have seen on ebay like £1000 power amps going for £300ish or whatever that would be great.

 

I look forward to responses!

 

post #2 of 7
Thread Starter 

Bump ... anybody??

post #3 of 7

The pre-outs on all of the little-dot units are 600ohms, which is pretty standard, so compatibility should not be a big issue.

 

I’ve never used an MKIII or MKIV but I do have two Little-Dot tube amps from their prior series, the II+ and II++.  Both function excellently as pre-amps.  I use them (either one or the other) in conjunction with two large vintage Yamaha amps to power two pairs of vintage JBL speakers.  It’s difficult to pinpoint what I feel is “lacking” because in any situation where I found something lacking I’d just change my tubes around until I found a better match.

 

I’ve had this setup for a number of years now and it continues to blow me away every time I listen to it.  In addition to the warmth the tubes provide it also seems to make the sound livelier and more energetic in general.

 

The amps I use probably aren’t the sort of amps you are looking for, but even though both date back to the 70s they have pretty impressive figures.  240wpc into 8-ohms, 20hz-30khz, 0.005% THD.  Both amps in the picture have almost the same internals; the bottom amp is merely the pro version of the top amp.  You can find some pretty amazing deals on amps like these on eBay, especially the pro amps.

 

Pardon the dust :)

 

2amps.jpg


Edited by GotNoRice - 1/8/11 at 10:54am
post #4 of 7
Thread Starter 

Hi thanks for your input!

 

Wow those are some great figures and a V nice set up

 

I have my dads old Vintage Marantz 1072 which has ... the following figures

 

THD 0.08% FR 15hz - 60kHz  +=-1db

 

Im not sure what this means exactly.. but i dont find the amp particularly articulate but maybe thats because of my speakers B & W DM303 but my source i believe is okay with a decent sigma DAC  inside the Audiolab 8000cd

 

I tried using the pre amp on the LD MKIII to go into the tape loop of the marantz, i found the sound to improve, tighter bass, warmer sound but at loudish volumes it sounded a bit off... maybe im just comparing the sound to my grado headphones. I havent started tube rolling however, and im still using the stock tubes.

 

Anyhow im wondering if you can assist me here as you do use the LDMKII as a preamp... The volume nob on the LD and on the marantz also turn and adjust the volume... which one of the two do you keep low? Also as you might know the LD MKIII has gain switches... currently it is set for high sensitivity with a gain of 3, but for the AV set up would you recommend a gain of 10?

 

post #5 of 7


 

Quote:

Originally Posted by Brumagician99 View Post


I tried using the pre amp on the LD MKIII to go into the tape loop of the marantz, i found the sound to improve, tighter bass, warmer sound but at loudish volumes it sounded a bit off... maybe im just comparing the sound to my grado headphones. I havent started tube rolling however, and im still using the stock tubes.

 

Anyhow im wondering if you can assist me here as you do use the LDMKII as a preamp... The volume nob on the LD and on the marantz also turn and adjust the volume... which one of the two do you keep low? Also as you might know the LD MKIII has gain switches... currently it is set for high sensitivity with a gain of 3, but for the AV set up would you recommend a gain of 10?

 


The units I have (II+ and II++) actually pre-date the MKII but they are fairly similar.

 

I looked up the Marantz 1072 and it does not look like it has pre-out & main-in jumpers.  Many vintage receivers/integrated amps like that will have those connections, which after you remove the jumpers would allow you to feed the pre-amp outputs of another unit directly into the amp section ("Main In") of the receiver/integrated amp.

 

Example:

marantzpreout.JPG

 

The tape inputs (or any of the inputs) on the 1072 are expecting a fixed level input from a source, which is probably why it sounds bad as you increase the volume on the little-dot.  Unfortunately I don't know of any way for you to hook up your little-dot to that integrated amp.

 

One thing that is sort of nice is that many older vintage receivers that have stopped working likely only have issues somewhere in the pre-amp section.  The amp sections of these units aren't particularly complicated so they tend to be a bit more robust.  I've purchased a number of receivers for as little as $10 such as a Pioneer SX-1050 (125wpc into 8ohms) that had a completely non-functional pre-amp section but I just fed my preamp right into the main-in jacks and the amp section still worked perfectly :) 


Edited by GotNoRice - 1/8/11 at 5:32pm
post #6 of 7
Thread Starter 

Bump any body else got any recommendations for which power amp i should buy from the ones stated above?!

post #7 of 7

I intend to purchase Little Dot MK4 SE (headphone/pre amplifier) to work with existing Bel Canto REF150S Class D switching power amplifier. I reckon matching between these two equipments involves impedance and signal level. While impedance matching can be achieved easily for most power amplifiers (600 ohm output vs 10k ohm input with RCA connection), there is serve mismatch in maximum signal level (10 Vrms output vs 1.1 Vrms input). In other words, volume control of the Little Dot MK4 SE preamp must be set below 1/10 of full scale to avoid maximum level at speaker outputs of the power amplifier. Many power amplifiers such as the Bel Canto REF150S do not come with any volume control and have a fixed gain of 27dB which make the matter worst. Fortunately gain of Little Dot MK4 SE can be set through switches for 3x,4x,5x and 10x.

 

I have sent email to David (little.tube@gmail.com) yesterday for the issue of mismatched maximum signal levels and still awaiting for his answer before making purchase.

 

Six months has passed since your first post, what kind of power amplifier (input specifications ?) you have settled with to work with the Little Dot pre-amplifier ?

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