Universal Audio SOLO/610

I have had the Solo 610 since mid-2009 and I can emphatically say it is a fun pre to use. Fun because there are so many different sounds to be had with this unit. With different Gain and Level combinations, you can easily go from “big and clean” to “big and fuzzy”, but you should understand that it has a certain harmonic warmth to it even in its clean settings. The effect of the impedance switch is way cool, allowing a choice between low and high impedance for either the mic or DI input, with different impedance range for each. For mic input, the impedance choice is 500 ohm or 2K ohm, and for DI the choice is 47k ohm or 2.2M ohm. On mic input, UA docs say the low impedance setting is for dynamic mics and the high impedance setting is for condenser mics, but UA emphasizes that there are “no rules”. I have found that it is always worth trying the high and low setting for any mic you use with the 610. I have found lots of variation in sound by using this switch alone.

The UA 610 imparts a big sound to vocals and acoustic guitar, making it a fantastic choice for the singer/songwriter soloist and other sparsely-tracked projects. It seems to match up well with lots of mics. I recently conducted a shootout of mic-pre combos for male vocals, and the Solo 610 was chosen as the best pre matchup for 4 out of the 7 vocal mics in the shootout. It also shines on bass DI, and I love it as a mic pre for acoustic bass.

The specs say it only has 60 db max gain on the mic input at 500 ohms, but I record a lot of quiet sources and have never been disappointed in its gain, even with ribbon or dynamic mics. In fact it seems to have as much or more gain than several of my preamps rated at 70 db. It drives my SM7b just fine with Gain at 5 and Level at 8.

FYI, UA recommends powering up the Solo 610 about 20-25 minutes before operation so that the tubes and transformers are at proper operating temperature.

This unit is well-built and has been an extremely reliable performer.

This is my go to pre for anything harsh that needs to be softened. I find that this preamp handles shrill signals in a very pleasing way,making them much more usuable and not as ear piercing. It is useful on thin sounding vocals and harsh guitars.

On inside kick/snare/toms I found it to soften the transients a bit more than what I would want (at least for the aggressive music I record). It does work well as an outside or sub kick preamp.

As a bass/key DI it has a nice tube-like squishy low end when driven correctly. It doesn't handle low B strings as well as my Radial J48 or Sebatron DI

I've also gotten some of my best baritone sax recordings with a UA610 and a Coles 4038

There are a ton of tonal variations to be had in this box, between the
impedance switch and the input/output gain knobs

It is built well and I have no doubt that it will work for years to come without a problem.

The Solo 610 is notable for its abundance of features compared to other preamps. In addition to Direct Inject input, you also have selectable impedance, and a two stage gain section for tonal control, as well as the usual pad, phase invert controls.

I used the Solo 610 on a lot of sources with good luck, notably bass, acoustic guitar, and electric guitar. I preferred the Solo 110 for vocals most of the time with condenser microphones, but I did like the 610 with dynamic vocal mics such as the Shure SM7B. This preamp seems tailor made for bass guitar, whether DI or miked up, it's warm and fat. I also like the way it softens an acoustic guitar track. You can get some really classy vintage sounds out of this box, and in my world, that's a delight.

The variable impedance was very useful to me for tuning the tone of dynamic microphones, many of which seemed to love the "low Z" setting.

I tried different tubes and found them to provide subtle shadings of difference, and ended up with a JAN GE 5751 in the first position for a slightly cleaner tone, although the stock JJ 12AX7 sounded excellent.

The Darth Vader appearance of the unit is something to love, and it seems built to last. I only occasionally ran into headroom issues, usually when trying vocals.

I like listening back to my recordings made with this preamp, the sounds are warm and inviting. A perfect preamp for those looking to upgrade or expand from a basic setup, or for those getting started looking for a useful single channel. The Solo 110 is a perfect partner, if you can find one.

I think the trick to get this thing not to clip on highly dynamic sources is to crank the first gain knob, and not the second level knob. Crank the first knob way up, as far as needed even to 100%, and then bring up the level only just as far as you need to get the right level. With an SM7 I got clipping on vocals when I set the second level knob to 100% and the first gain knob lower. Try to get as much gain as you can from the first knob, when and if you encounter clipping.

This discontinued preamp and DI unit from Univeral Audio was the solid-state brother-sister to the Solo 610, a tube unit. Like the Solo 610 this one also has a Direct Inject input, a variable input impedance, and a two stage gain section for tonal shaping. The Solo 110 is modeled on the "vintage" setting of the larger 4110 and 8110 (discontinued too) rack preamp units that also had a clean mode and a soft limited mode.

The sound is clear and bright but not harsh, and with a sort of friendly analog warmth that's variable based on how much gain you dial in on the first control, that I found especially flattering to electric guitar, acoustic guitar and vocals, although, I would expect this preamp to be very suitable to any number of sources had I seen the opportunity to expand its use.

I would attribute this sound quality to the design, but also to the use of a transformer on the input, which has been a hallmark trait of many of the beloved classic preamp circuits of the past. I find transformer balanced preamps to be more musical for most sources, for my aesthetic. I liked the softly shaded clarity this brought to my productions. Between this, the thicker sounding 610, and a four channel utility preamp (Sytek) I felt like I could get anything done and produced a lot of really excellent recordings with a pleasing sound stage. These were my first high-end preamp channels and open my eyes to the possibilities of recording with world-class equipment. They were miles above any all-in-one preamp-converter-interface box I had ever used and set a benchmark for the quality I have come to demand.

The low-Z setting really brought to life a lot of dynamic microphones, and I used it often. The DI sounded really nice on electric guitar, but I would use the 610 more often for bass guitar.

I felt that the Solo series offered a great value, and performed excellently in my DAW based setup, providing a classic sound. I appreciated the single channel form factor as it allowed me to purchase one channel at a time on a realistic budget.

The Solo 110 is well built and seems equipped for any recording task, so I would recommend one highly should you encounter this specimen on the used market.

These are interesting preamps. They kind of flew under the radar of the "tube" 610 series, and made one think they might lose out if they didn't get the tube version. But using this I accidentally got my favorite take I ever tracked.

I was recording a band live, with vocals to be dubbed later. But guitarist/vocalist and band needed him to sing while they played, so I setup a beta57 vocal mic to feed everyone in the headphones. the 110 was pushing just enough overdriving color, when I ran it through my console, put some eq, and crammed the compressor to ridiculous levels. I just wanted to make sure everyone could hear the guy. He was sitting away from the band, looking towards them (mic aimed away from the band). I hit record and they played through the track pretty darn good.

On playback the drums just came to life like harmonic explosions, with a giant room sound. and the vocals came in with a creaminess that at a whisper sounded haunting and dreamy, which turned to screaming without a need to touch the fader... My compressor works

But as I started mixing I could notice a certain indescribable quality to that one Track. It made me want to listen to it, and get lost in it. Undoubtedly it was the preamp, the solo 110. There were lots of other factors, but what I liked the most was the transient "shsh" kinda sound, sort of distorted, yet not noticbly so.
The band loved it and they decided not to do overdubs.

The unit feels like a tank, the controls feel like something a pro would design... You can tell its not a bunch of cheap parts. And I'd say skip the tube 610 and get the 110, if you can find one.

Great Pre!

This is such a great DI/pre. I used it on every Bass track on my last album. It really does create a big and warm tone.

I also used this on the Kik in my drum tracking. I must say it didnt give me quite the bite i wanted. it left it feeling slightly muddy and a little too boomy for my taste, however it was a great sound to start off with. nothing a lil Eq'n cant fix.

Vocals & Ac guit I found that this really does add alot of character. Warm and Big.

This is really an amazing deal for that great tube sound. i bought mine and i'm extremely happy with it. It's built like a tank and feels like it looks.

The only reason i would give it a 9, in sound and in features, rather than a 10 is that some of the controls are in the back which makes it difficult to switch around, and with the Warm Big tone, it sometimes creates unwanted mudd in a mix. But for the money, i'd recommend this to anyone looking for a tube pre.

A little over a year ago I started to build my home/project studio - after many years out on the road. Having produced, and co-mixed a number of albums in the early-mid 90s - back then, I was fortunate enough to have worked in a studio using 2" decks about 95% of the time.

Needless to say - when I started the mission of building a home studio - I knew I was tackling getting into the digital world, and building my proficiency with PT. Through all that though - I knew that the main course I wanted to plot in building the studio was to have as much analog character as possible (with pre's and mikes) to try to set the "warmth bar" as high as possible in my recordings.

Enter stage left - the UA610. A great engineer and touring friend of mine told me "if your goal is to start with a warm, tube-pre, you need to get the 610. And if you ever decide to play out, you've got a really cool looking D.I."

WOW was he right! After doing a bunch of recording and testing, testing and recording over the last year to get things where I want them - the 610 has stood out every time as a KILLER source for vocals, acoustic guitar, mandolin - just about anything I can throw at it with the right mic.

I was so impressed with it in the first three months, I went out and bought a second one. And I'm really glad I did. Recently bought a 4-710 about a month ago, and am about to start a new album session with some friends. This round I'm going focus on just using the 610s for vocals, to try and make them stick out a little farther in the mix.

No complaints - and in my opinion, a must own for any studio.

I have one of the old units with the (best) 12ax7/ge jan 6072a combination and it is incredible on bass and acoustic guitar. It's really good for everything else also but these 2 instruments are where the 610 shines. Condensers usually work better on high impedance but this is a box that rarely doesn't sound great (mediocre is an unknown word). I refered to the tubes combination because if you have a newer unit with a 12at7, you'll have to change that to a gen jan 6072a (+50$). I propose that because i already made the comparison. The 12at7 does not saturate as easily as the 6072a, but the latter has a fuller and more clear sound at conservative settings (which are enough for everything). The talk about ua distorting the sound is not understood to me. Never occured to me. If i want to distort the box, i'll have to crank it on purpose.
Another cool move you can make is change the input tube with a better one. I put a Telefunken instead of a JJ which was a bit harsh on the midrange. The sound is more analytical now with more depth extended response and the same smooth sound.
So grab one if you want the classic vintage sound and you 'll get a fine tube di also.
Highly recommended.

Sound Quality
This pre sounds like pres that cost 3 times as much. It has that analog tube warmth you expect from a high end pre. I use it primarily on bass, synth, vocals, and guitar. For bass it has nice creamy low end. Very rich sound. On my Moog Little Phatty it really brings out the low end and helps it sit in the mix better than just going straight into my interface (MOTU 896HD). On vocals it is OUTSTANDING. The male vocalist in my band has a very high voice and we've always had trouble trying to get his voice to sit in the mix. This baby does the trick, absolutely perfect. On guitar it is awesome. Really gives it a nice, warm, vintage tone.

Features
The only thing it doesn't have that I wish it did is a nice VU meter. Other than that it is loaded with features. Giant gain and level knobs, direct in, phantom power, hi-z lo-z switch... everything you could possibly need (besides a VU meter).

Overall
I have used plenty of preamps, and I find that nothing in this price range compares. For me, I need something to give my material a nice, vintage tone. The tube warmth and tone this adds to audio is unreal. I did quite a bit of research before picking one up and I can say with full confidence you will not be disappointed. I read a decent amount of concern in reviews about the low input overhead. I haven't found that to be a problem at all. In fact I have no idea where people come up with these claims. If you are looking for a high quality, professional mic pre under $1,000 there's no other way to go.

The UA Solo 610 tube mic pre has been a great addition to my composing studio.

Simple controls:

Front panel:

Input gain
Oupute gain
Mic / DI switch
Lo-Z / Hi-Z switch
Phantom power
Lo Cut filter / flat
Polarity reverse switch
DI ¼” jack and DI thru (for also driving an amp)

Back Panel:

XLR input and output
Ground lift
Output level selctor – Mic / LINE


You can overdrive the input stage by raising the input gain knob, and moderate level with the output, which has so far sounded best on bass, and grungy vocals for an effect

If I am recording guitar or bass on a production music job, I am usually going direct in. If its for an album type project, I mic an amp and am happy with the way it works.

For quick jobs I have found for my uses that gain between 1-5 and output level between 5-10 yields reasonably clean sounds on guitar and bass, so using an amp sim or similar in a DAW sounds fine.

For either DI or using a mic, I have really liked the Lo-Z / Hi-Z input selection switch. I am sure that there is adequate tech write up on the actual specs of this one on UA’s site, but for me its “brighter and higher output” or “rounder high end and less output”. Just flicking back and forth on a mic’d acoustic guitar with either make the top end pop out, or tuck it in a little depending on the kind of tune I am working on. Great feature.

I have used it on mobile jobs a number of times, and moved a number of times since I bought it in 2008, and it is still working great and have not had any tube problems.

I might buy another but at this point would probably look for something with an inline compressor (like the LA-610) for a different flavor.

Alright, here is a review of this bad boy.

i have used this for around 7 months, with multiple mics, so i think i will be able to give a decent opinion. First off, i bought this to complement my vocal recordings. i use a akg percetion 420 mic, and i thought that i finally needed something better than the preamps on the front of my sound card. The first minute of using this, i noticed how much better my vocals sounded. The begin, the mics high end is a little brittle, being that its not a 1000$ mic. But the solo 610 was able to tame that high end, make it smooooooth like a tube sounding pre should, but most importantly, kept the overall sound clean. This is hard to do with a tube preamp, but the solo has achieved it.

The next great thing about this is the direct input. I was always recording my electric guitar with direct input into my sound card, but the signal was weak, forcing me to boost it in the DAW i use. this creates a very fake and muddy signal. The solo not only give a clean signal, but provide a smooth tube signal, as if i was recording a tube amp! soooo sweat for someone like me on a budget.

This piece of gear has done everything i ever expected and more!
definitely worth checking out!

Overview

The Universal Audio Solo 610 pre-amp is a portable single channel version of the classic 610 preamp. Featuring input and output gain, instrument DI input, hi and lo-z switch, phantom power, lo-cut switch, and DI through.

In Use

The Solo 610 is a smooth, rich pre-amp, and brings to mind what you would think of when you think tube gear. While maybe not as defined or extended in frequency response as a Neve or Great River it can be the perfect match for certain sources or microphone's particularly vocals and ribbon's. Also works great on bass allowing you to dial in some grit with the gain controls. The instrument throughput is also really convenient when tracking bass or electric piano in the studio and has made it my go to DI box. The multitude of switches allow you to dial in just the right sound and go from line in, to mic, to instrument with ease. The ability to send mic or line level signal along with the previously mentioned throughput would also make it a great option for bass/keyboard players live setup giving you flexible and convenient control of both your amp and DI sound. Not to mention giving the studio engineer a wide variety of options to experiment and create different sounds from smooth tube's to fuzzy distortion.

Summary

The Solo 610 would be a great addition to just about any studio based on it's portability, flexibility, and quality and would also be a worthwhile to check out for most bass or keyboard player's setup's to add extra control and depth to your sound in situations where you need to DI. The price also makes it attractive for smaller studio's where a couple hundred really makes a difference.

This Universal Audio Solo 610 pre-amp which is hand assembled in the USA is incredible! For any studio or person looking for a single channel pre amp than the solo 610 is a great option. The chassis is solid steel and the build quality is very high.

In order to maximize the effectiveness in your recording chain the most fundamental parts are your microphone, Pre-amp, and the quality of analog/digital converters in your interface. For many people who are starting to build their chain, spending over 1000 dollars for a preamp is quite expensive so I believe that an effective way to get stellar sound and incredible build quality at a good price is through buying a single channel pre-amp; hands down one of the most important single channel preamp to consider is the solo/610.

In use the sound is big, warm and detailed; the gain and level knobs can be adjusted to really change the sound. By turning the input gain lower and the output level higher the tone will be cleaner and more transparent. If you choose to turn up the gain and turn the output level down you will receive a more harmonically distorted sound which will sound bigger.
If you are searching for a pre-amp to really bring up the sound quality in your recording chain and you are interested in a single channel medium than the Universal Audio’s Solo 610 is a supreme choice to consider.

Bought one of these used for 500 bucks. Wasn't very fond of it at first -- it was noisy, distorted easily, and had a very low output. But I was stuck with it. Figured it might need new tubes since it was five years old, so I replaced the stock JJ's with a pair of Genalex Black Lions (ECC81 and ECC83 -- a $90 upgrade). Holy cow! Suddenly I had a hot output, low noise floor, and tone to die for -- tight bottom, punchy mids, and silky highs. Though not quite as detailed as my solid-state Pendulum Audio SPS-1 preamp, the Solo 610 made my vocal tracks POP in the mix like never before. Also works great as a DI for my live acoustic guitar setup. Love the portability. I don't use it for all my recorded tracks because the Pendulum preamp is better for non-lead tracks that don't need to sit high in the mix. Still, a highly recommended front-end that will make any so-so mic sound so so great. Spend the extra 90 bucks to upgrade those disappointing stock tubes -- you won't regret it (and I'm a guy who used to think all that audiophile vacuum tube snobbery was complete BS).