LA610 returns a (special edition)

CoolCat

Well-known member
I grabbed a LA610 again for a second test drive. This is the special edition...cool, only 500 made , basically some upgrade options like transformers and tubes. $1000 used, mint condition.

I jotted down all the preamps and stuff Ive tried at least going back to HR years, main 2 things noticed as is "personal preference...ymmv" is:
1) I like the flat 19" rack gear that stacks and can sit on my desktop table. So over the years the small 1/2 sized and the cool ISA One looking units didnt do the ergo thing for my small space. The small MS1b kind of slid around etc..the half space size etc...19" rack for me.

2) after going through a bunch of preamps including interfaces and realtime plugs seems I found the "studio sound" I was seeking is in the compressor color and not the preamp so much!!

off the top of my head...preamp list ...
DMP3, JoeMeekVC1Q, ISA One, Focusrite platinum, Symetrix 528E, ART MPA gold and then Blue Light REFERENCE MPA, Joe Meek VC3 old and 3Q new....then JoeMeek OneQ ...rebought the Joe MeekTed Fletcher VC1Q , ISA Two, Lindell SX rack...RANE MS1b then RANE DMS 19".... Mike E EL9 and LA610mk2....ART TPS pre/comp w/ overdrive

LA610 is a cool analog tube vibe with transformers, $1000 was a bit more than planned but it also has a DI thats been on my list and its a Preamp with Pad, with EQ, and the LA- Comp/Limit which is lovely and super easy to turn the big old vintage vibe bakelite large knob. No programming , no mouse , use the ears....simple. Thats why I wanted to testdrive it again.
I wanted to compare it again to my ART TPSII if nothing else, but this time keep it for a longer test drive.

LA610 SE arrived and popped the lid immediately, WIMA's and Cinemags, and Phillps GE tubes in all slots.....what kind of genius's can design and build this stuff?

Being anal I did notice one tube looks to have a oxide? flake off its plate?
 

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Heres picture of the "plate oxide flake?" and a good tube...see the white is not there on one of the tubes (pre Level tube)

Any tube experts think this is a problem?
 

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mixsit...I don't know if I have much to add.

I feel better now at least knowing the unit is working well. Glad Im not posting problems.

1)Initialy plugged the LA610 Line Out to Interface Line IN with a XLR to T/S cable and was getting a very small weak wave on the Reaper track. It did sound barely ok through the headphones. Playback was so thin I thought "defective! unit a ripoff!" lol or the tubes were burnt out$$ etc....defective!!.:eek:

2)Trouble shooting I tried LA610 Line Out to Interface Mic In, with a XLR/XLR cable, mucho louder but sounded bad. The LA610 manual states "Polarity moves the Hot from Pin to Pin on Line Out if using T/S and not TRS." so I tried # 1 again, Line Out to Line In..

3)Went back to Line Out to Line In config with a mic cable XLR/XLR but added a Radio Shack male connector I had in a drawer, which gender changes XLR to 1/4...because I didn't have a XLR to 1/4 TRS.

It works normal now and its louder, much louder and totally different, huge difference in volume and full sound and the Reaper Wave is controlled to be larger or smaller as I turn the big black Bakelite Gain knob. very cool...


Im not sure why this Radio Shack plug, mic XLR to 1/4 helped so much? Is the LA610 Line Out and the Interface Line In some major mismatch? Was my cable bad? Radio Shack p/n 274-016 LowZ to HiZ. Adding this thing was a huge difference. So huge I didn't think the unit is faulty now. whew!...
Radio Shack is a Z changer of some kind. Whats going on with the transformers? Will a normal XLR to TRS work as well or do I need a Z change?
 

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Heres picture of the "plate oxide flake?" and a good tube...see the white is not there on one of the tubes (pre Level tube)

Any tube experts think this is a problem?
I think you're referring to the mica insulator that electrically and physically holds the elements of the tube. A bit flaking such as shown shouldn't be of any concern. Mica is inherently a layered flaky material. The plates are the darker gray structures in the tube.

"mi·ca
ˈmīkə/
noun
noun: mica

a shiny silicate mineral with a layered structure, found as minute scales in granite and other rocks, or as crystals. It is used as a thermal or electrical insulator."
 
thanks, interesting. Mica the Insulator.
It seems to work. I ordered a spare, it will cover all 3qty 12ax7 if needed. I have a hunch these tubes are the original from 2008-09 or so...

Im curious on the volume issue this morning too. Was it a impedance or just a bad cable?


the LA610 Line Out is 80ohm
the Interface Line In is 10 k.
Anyone know if these values are normal? if yes....
then I need to go get a good XLRfemale to TRS.

ADD>

man Im confused, went and bought a TRS cable and there was hardly any volume from the LA610 to the Interface and the Reaper wave was barely seen. as before with the other TS cable.

But when I used the radio shack impedance thing, the volume was full and loud and all seemed good to go.

guess theres some reading to do.

maybe the Line6UX8 Line IN to the LA610 LineOut is causing it?

1) cables are good as the Art unit showed
2) could it be a old tube set?
I wouldnt think so because the needle on the LA610 seems to be fine and showing good needle movement.

I used the TRS cable on the ART TPS and no issues with the cable, even using the same interface channel.


more ADDED> weak sound on the LA610? FROM UA site.
What are the symptoms of a bad tube?
The symptoms of bad tubes are easy to spot… they stay out late at night causing all sorts of trouble, never pay the rent on time, and never call their mother on Mother’s Day! Ahem, but seriously. Most of the time the symptoms of a bad tube are clear enough: microphony (high pitched whistling), lack of volume, loss of bottom end, a ‘thinning’ of the sound, and loss of all high frequencies. Also, distortion in audio signals like intermittent pops, flickering, spikes, crackle, a thin sound, and spitting thermal noises can indicate a tube that is past its prime. If you have any of these issues it is likely you need to replace your preamp tubes. Other times the symptom is even clearer — there’s no output from the unit at all.
 
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Do I spend cash on a tube swap?

So Im still not getting the vibe this thing is working right. I changed out the 3qty 12ax7 and no change.
It could be two other tubes I suppose I could buy those and run a test. but that's another $40 probably.

My microphones are very good medium output, they aren't weak and they aren't "hot"...KSM27 is 16mv/pa, the AKG C2000B is 20mv/pa.
According to the VU needle everything is working well, perfectly actually.

But the output to the interface LINE IN seems thin and trebly, imo.
Compared to my ART and RANE and straight into the interface MicIn...the LA610 is definitely not giving me a wow-vibe.

this is my second test drive and I recall really liking the LA610.

I sent UA Tech Support an email asking 2 things.

1) Thin and trebly...yet everything is working (which is probably the tube or they will say SEND IT IN!!! for $$$$$$$)

2) I asked why does adding the Radio Shack LowZ to HiZ TS connector quadruple the volume? then its almost too loud...unbelievably hi-gain and cleaner and full.

But I shouldn't need the Impedance thing,right?


I'm leaning the output tube has gotten old. It appears these are the originals NOS from 2009 SE upgrade.


As of today my Art TPS is kicking this $1000 units ass.
 
Wow, I hope you get it working right. I'd love to hear a sample. This is the current Tone Thread:

https://homerecording.com/bbs/equip...e-mix-thread-394377/12/?highlight=Tone+in+mix

Well, Im about ready to ask for a refund when I put on the openbacks and fired up my "mix" playback to compare some files.
This morning plugged into the 610 and the ART TPS....

theres a really weird thing going on imo.

the LA610 everything on the panels is working, the VU meter up to right levels etc... but in my DAW(Reaper) the wave is tiny and thin, -18. And that's with really having the volume up on the 610 at 0..to touching the red some...my interface led are green, and the VU on my interface all looks great.
-18 to -6 etc...

but the DAW wave is trebly and tiny...Im repeating myself.

then I plugged same mic into the ART TPS, same output cable TRS from ART to same interface channel 4....and huge wave, huge sound, full and anything from clean to distorted guitar overdirve etc.... Reaper Wave is large and DAW output easy -6 but I could go to the moon with volume if I wanted to.

I'll go back through my wave files when I test drove a LA610 and hope it confirms something.

Its weird the RadioShack Impedance plug quadruples the volume?
I don't understand that at all either.

for $1000 I didn't want a project to fix though, I was expecting cream and butter and EMI 1960 sounds....but for now Im getting more of that from my $100 ART TPS?:rolleyes:
 
Oh, that sucks. Yeah, get your money back. There's a better one out there.

ART rocks. My input chain for the past 4 years has been an ART Pro MPA II preamp into a Pro VLA II compressor/leveler. Best $500 I ever spent.
 
maybe the Line6UX8 Line IN to the LA610 LineOut is causing it?

Maybe, kinda, sorta........
I went to Line6's site for the specs for the UX8. Line inputs are 10kohms and that's OK, but the specs state the line ins are 'unbalanced' which is intended to take a TS type plug (this sucks cause you'll lose about 6dB signal vs balanced). You mentioned trying an XLR to TS cable. Do know if this cable is wired to 'convert' the balanced XLR connection to an unbalanced TS? It likely is wired to do this, but maybe worth a check. It needs to be wired so pin 1 and 3 are tied together and pin 2 is the 'hot' (see image below). The Radio Shack adapter does the balanced to unbalanced thingy and because of the transformer it may give the signal a boost, but may alter the sound as well.
A cable that does balanced to unbalanced ....... Unbalanced Interconnect - Hosa Technology

I couldn't find specs on the UX8 line inputs for gain/sensitivity. How are you setting the Gain and Levels on the 610? The Gain switch also affects 'negative feedback' in the circuitry which alter the sound a bit, so take a look at the manual so you understand what it does.
 

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well I'll be darned...the other testdrive LA610mk2 wave file is exactly the same.
I found my test drive LA610mk2 file and it too was at the same volume and what seems thin and weak signal.
actually it sounds identical. the wave is -18 and huge gain is needed to get it to a "loud" full sound.

in a way Im happy that this unit is "functionally fine". so maybe is there something to do with my setup?
but the rane and art and many others Ive had I don't recall this issue.


and why does the impedance match radio shack thing bump up the volume so much?
 
Maybe, kinda, sorta........
I went to Line6's site for the specs for the UX8. Line inputs are 10kohms and that's OK, but the specs state the line ins are 'unbalanced' which is intended to take a TS type plug (this sucks cause you'll lose about 6dB signal vs balanced). You mentioned trying an XLR to TS cable. Do know if this cable is wired to 'convert' the balanced XLR connection to an unbalanced TS? It likely is wired to do this, but maybe worth a check. It needs to be wired so pin 1 and 3 are tied together and pin 2 is the 'hot' (see image below). The Radio Shack adapter does the balanced to unbalanced thingy and because of the transformer it may give the signal a boost, but may alter the sound as well.
A cable that does balanced to unbalanced ....... Unbalanced Interconnect - Hosa Technology

I couldn't find specs on the UX8 line inputs for gain/sensitivity. How are you setting the Gain and Levels on the 610? The Gain switch also affects 'negative feedback' in the circuitry which alter the sound a bit, so take a look at the manual so you understand what it does.

wow, thanks for that.... I'd buy you a beer if you were here! how did I overlook that? I assumed the 1/4" was the TRS style! on the Line6UX8.

the radio shack transformer/impedance thing is TS....not TRS, so maybe that's it. it makes sense.

I need to double check but the LA610 is +4 out, and it mentions its ok to run into a mic pre on a interface IF it has a pad, if not they really recommend the LINE IN on the receiving interface.

This is really a good find, thanks so much.
 
LINE6UX8 INterface

Line:
8x 1/4-inch rear panel unbalanced line level inputs
Impedance: 10 k


LA610SE (La610 not mk2)
Polarity The front panel toggle switch labeled IN  and OUT  determines the polarity of the LINE OUTPUT. When IN  is selected, pin 2 is hot (positive). When OUT  is selected, pin 3 is hot (positive).
Input/Output Standard XLR input and output connectors are provided on the rear panel. Pin 2 is wired positive (hot) on the LINE and MIC INPUTS. Pin 2 is positive on the LINE OUTPUT when the front panel Polarity toggle switch is down (IN ). Pin 3 is positive on the LINE OUTPUT when the front panel Polarity switch is up (OUT ).


This is getting somewhere, my mic pre in is balanced and does have a pad to deal with the LA610 +4 output. That might even be better.

Yeah Robus, the ART stuff is a lot better than I knew which is part of the comparison.
I personally like the TPS better than the silky, clean tubeness of the MPA which a excellent deal all around.
The TPS has a dirty ability to compress clean or get nasty...lol and its a DUAL channel for $185 brand new, used $85-$100.
Comparing to this high end stuff is making them look even better than I thought.
 
OK I found a XLR to TS cable, Pin 2 is hot, 3& 1 tied together.

So its better to float 3? or leave it on 1?

I'll try both. The same cable from my ART balanced out to TRS to UX8 Line In isnt having the same issues.
 
OK I found a XLR to TS cable, Pin 2 is hot, 3& 1 tied together.

So its better to float 3? or leave it on 1?

I'll try both. The same cable from my ART balanced out to TRS to UX8 Line In isnt having the same issues.

Leave pin 3 tied to 1. The ART is likely 'electronically' balanced on the output (no transformer), which may work OK with TRS. The LA610 I'm guessing has a true transformer output and if the ring of a TRS plug doesn't make a connection to ground inside the TS jack of the UX8 to complete a low side connection of the 610's transformer, then one side of the signal sees an open circuit and won't work well.

Do you have a mixer or similar with a balanced line in that you could listen to the 610 and/or other preamps to make a comparison that way?
 
Leave pin 3 tied to 1. The ART is likely 'electronically' balanced on the output (no transformer), which may work OK with TRS. The LA610 I'm guessing has a true transformer output and if the ring of a TRS plug doesn't make a connection to ground inside the TS jack of the UX8 to complete a low side connection of the 610's transformer, then one side of the signal sees an open circuit and won't work well.

Do you have a mixer or similar with a balanced line in that you could listen to the 610 and/or other preamps to make a comparison that way?

arcaxis....dude...you found the root cause. and theres some funny ironic extra notes in hindsight.

the very first cable I used was a XLR to TS....but I found out just now with my meter pin 3 was floated (it doesnt work on the transformer output LA610).

after you mentioned this I found another XLR to TS but it was like a homemade one from years ago that had 3&1 tied.... it came on like a healthy, loud, everything perfectly fine system now.

the line6ux8 non-balanced Line IN and the LA610 balanced Line Out was a "bad match". It ONLY works with the pin 1&3 tied together. and exactly as you said, the LA610 doesnt like pin 3 floating.

that was a great forum input and great details caught and appreciated!!
Im cancelling the REFUND request and will not need UA Tech Support when they respond.

It also doesnt have a hum like the impedance radioshack Z gender changer did.

Man this thing is so different! You were right on that too....total tone changed.

that was kind of fun! and a lesson in wiring I didnt know about! thanks again.
 
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Good to hear!!! :thumbs up:

Let us know what you think of it after playing with it a bit, particularly compared to the ART. I've kinda had thoughts of getting a SOLO/610, but the price tag even used is a lot more than any other pre I currently own. Lately I've been pretty happy with the Warm Audio WA-12 I've been using. Always the temptation to try something different unfortunately $$$$.
 
I dont get lost like that much but your looking up the UX8 and bringing all that transformer output and pin info was impressive and helpful.

well the 610 is on enough billboards to speak for itself. TwentyOne Pilots engineer....slammed the 610 into a 1176 blue stripe with a Sony C800G on Stressed Out an Heathens...young kids music but great recording of vocals imo.
Adele and the Rodes ClassicII into a 610(6176) etc.... very classic sound and simple for the tracking anyway.

for the LA610...flavor...after your "repair" theres many forum posts of the same issues possibly. 610/LA610 could be from someone with a wrong cable saying "this sucs and its horrible i sent it back"....lol Ive read other posts mentioning "no output!" "weak signal!! from 2004...0r 2008...etc... I cant help but wonder did they have the same issue as mine?

I never knew about the transformer outputs, as you mentioned.
Ive assumed all along my UX8 was TRS! balanced...and Ive looked those specs up many many times over the years. lol

Im reading a lot about low output mics, working well with the 610 pre....one guy sounded logical that these are old school designs befor the FET mics were invented and lower output of Ribbons and old NEumanns were more common. sounds logical...I dont know.


add> Weird wiring.... that Radio Shack thing ohmed out pin 2 was the tip as normal, but the 1&3 were not connected at all to the shield to pins 1&3 measured open.
Looking at the transformer drawing above thats right, theres no connection other than the transformer?
that thing increased the volume but adding a noticeable hum in the 100hz range, a bad buzz hum.
 
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