Dynacord Amplifiers

Dynacord Amplifiers

Postby nate_lamy » Mon Mar 16, 2009 8:52 pm

OK, start talking.
I've seen various cool looking tube bass heads as well as those sexy little coloured combos. Since I have too many amps as it is, I haven't bought one. Yet. How good ARE they?
User avatar
nate_lamy
 
Posts: 1171
Joined: Sat Oct 25, 2008 6:00 pm

Re: Dynacord Amplifiers

Postby Snap » Tue Mar 17, 2009 3:17 am

User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Re: Dynacord Amplifiers

Postby Snap » Tue Mar 17, 2009 5:19 am

In my experience old german amps are usually well built stuff, use to have good hefty transformers and clean and tidy circuits. Usually good components too.

Now let's focus on Dynacord. The biggest german manufacturer based in Passau and still in the bussines. Obviously, the more interesting stuff was made from the mid '50s to the mid '60s when the brand new solid state circuits almost put tubes away from their amps. The transition amps are still nice, usually hybrid amps having solid state preamps and tube power amps. Good for those looking for juicy crystalline clean sounds. If you ever liked the Roland Jazz-Chorus 120 chimey sound or Music Man amps, you will love those hybrids with some tube warmth added.

Excepting a few guitar (or instrument) oriented amps, most Dynacord amps were multipurpose, that's very Hi-Fi designs having a very wide bandwidth. Perhaps too wide for what we (guitar amp biased guys) are used to. Instrument amps usually don't go too low or too high in frequency, because the output transformers and the speakers cut the ends of the spectrum off. Not many guitar speakers go lower than 75 Hz or give anything beyond 5 KHz. This is why so many modern bass amps and acoustic guitar amps have tweeters added, to go higher than that. For electric guitar nobody seems to like to go higher, so we stay with our traditional chopped off non-linear guitar speakers. Allowing further treble to pass by could be ok for clean sounds for some folks, but it can get really ear piercing and unbearable if we allow all the increased harmonic content generated by overdriven tones pumping from our speakers. So, for bass and acoustic guitars these amps are excellent. For electric guitars, better chose not too bright guitar speakers. Stock speakers and Dynacord cabs are often overly bright and shrill for guitar use, but at the same time they pump a fat lo-end like true bass rigs. This would make some guitar players to smile for a life time. In most cases I prefer to avoid stock speakers and/or cabs and better plug into traditional guitar cabs.

To get an idea of how that shrill would be, think of a Vox AC30 (Matchless or Bad Cat) amp with the Cut control fully open. A simple cure for all those shrilling amps is what most guitar amps makers did in the past. Just tie a small cap to the phase inverter plates to cut the extreme highs and you are done. This was the solution used in most old Pre Black Face Fenders, Marshalls, Voxes, Oranges, etc... And any later amp derived from them. Vox amps and what's derived from them, have an adjustable variant for this. Their famous Cut control. It's the same idea but with a pot added to get some control over it. It could be a good idea on Dynacords if anyone wants that mod to be "reversible" allowing to get the original chime at will.

The main specific problem of the aged Dynacords are the coupling caps. They usually have Neokon caps which sound really good, but after decades in use they always tend to get leaky, so the best thing to do is replacing them all for fresh ones. If they are not bad yet, they will fail soon. For me, the best replacements for these circuits are old Mustards (if anyone wants to pay the expense) or modern caps based in their voice, like TAD mustards, Sozo, Mallory 150 and that sort. Orange Drops of course are good ones, but they will alter a bit the original flavor of these amps... and will add some more treble and bass to the whole thing, which I find that it's not very a desirable addition here. The TAD Mustards are the ones I use in my Dynacords, They sound excellent. It's not a bad idea replacing the small ceramic caps (ratty sounding non-linear caps in almost any guitar amp around. Used worldwide just because there's nothing cheaper) for good silver mica units. Almost any decent components dealer has them. They help to turn the trebles silky and juicy instead of ugly, sharp and shrilling. This last change is advisable for almost any amp around whoever they made them.

The main concern about getting old amps is tubes availability. Not a problem for those using the standard tubes, but so many old german amps (and US made Ampegs too) use not so common tubes. Beware of that before getting an oddball. Always check what tubes it needs. Better choose those with ECC83, ECC82, ECC81, EF86, EL84, EL34, EZ81, GZ34 and that sort. Fully available today. The ECC808 is becoming scarce and expensive, though those circuits can be adapted for ECC83. The ECL86 and ECL82 are still rather abundant and affordable. The EL12, EL500, EF40, ECC40, etc... are not in production anymore, cannot be found often and some are expensive, so if you are not into tubes or electronics, better make your life easy and choose amps with the common tubes.
User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Re: Dynacord Amplifiers

Postby Snap » Tue Mar 17, 2009 8:25 am

After this general overview, let's talk about instrument amps. Why instrument amps? Well, before the sixties about no specific guitar amp was available in Germany. They made instrument amps intended for bands, so they use to have from two to four channels with separate microphone, accordion and tape or guitar inputs. Remember that most early '50s US made guitar amps had accordion or mic inputs too. They were not so specific.

Amongst the numerous Dynacord '50s models there is a "fab four" group. These are the MIGA16/MV15, DA15/DA16, KV10/KV12 and KV6.

The good thing about all these Dynacords is that they always have a built-in extension speaker connector. In the KV6 is permanently linked to the internal speaker, but can be easily removed with an added switch. The bigger amps have the switch already, so the internal speaker can be muted. A very welcome feature! Usually the original Elbau speakers are too Hi-Fi with a broad frequency band. They give way more low-end than what these small "Kassette" cabinets would ever keep up. So they tend to sound flabby and distort the bass too much. Also the treble can be very piercing. If using the internal speakers, better be easy on the equalizer. The best way to go is using a good external guitar cabinet.

The KV6 is a small 4 watt amp. A perfect practice amp with two inputs and a small speaker. I haven't tried it yet, but I die for one in decent condition. Most of them are trashed with signs of very intensive use. I'm pretty sure it sounds gorgeous plugged to a lo-power Celestion. The good thing about Dynacord is that the modest amps were built with the same quality and craftmanship as the top end models. These babies are really well built compared any other entry level amps. It's very satisfying looking at these tidy hand built point to point circuits and the chunky transformers, not penny pinching here.

The KV10 filled the midrange range. It has from two independent channels and a single common tone control to four separate channels depending on the versions and years (the full band in a single amp!) The early version had those odd tubes I talked about, so it's not an amp I would buy. The second version had ECL82 tubes for the phase inverter and power section. These tubes put out 8 to 10 watts from a push pull amp. They tend to distort very early, even earlier than the always ready to distort EL84. Not an amp for clean sounds, but a nice one for old fashioned dirty bluesy tones. The KV10 was replaced by the KV12 loaded with ECL86, a better and juicier tube. The ECL82 sounds a bit duller in comparison. Again a distort ready amp. Great for the crunchy stuff at reasonable levels. For me, the one to look for in this range, but way scarcer than the KV10. These squared boxed amps were ugly compared with the rest of the highly appealing Dynacord range.

The MV15 and the Miga16 amps are two nice compact and small 15 watt metal boxed heads. No combos this time, so no problems about dealing with speakers, just use your favorite guitar cab. The MV15 is more PA oriented while the Miga is the instrument specific version. I haven't got the schematics yet, so I don't know the actual electronic differences, but I guess they are very similar and the main differences are the input sensitivities and voicings in the different channels. The MV15 has two different mic channels and a third channel for turntable or radio (it has an specific radio input) for some backing tracks for the singers. Who actually invented the karaoke? :lol: I haven't got any yet, so I haven't tried it, but looking at the specs, the second channel should be perfect for guitar. The first channel should be something like the low sensitivity input of a guitar amp, the one noone uses on old Fenders or Marshalls. And I guess the third channel pickup input would be like a built-in dirty distortion device. It has a huge sensitivity for a turntable pickup and it's probably voiced for that, so I guess it will sound weird and easily overdriven by a guitar pickup. The Miga 16 was offered in a few versions along the years, some having an accordion input, some with just two guitar inputs and always a mic input just in case you want to sing along or play some harmonica. This is the amp I'm currently looking for. But don't show up as often as MV15s.

The DA15 and the later DA16 are the most abundant of them all. These are great small and light weight portable 15 watt combos. They have two removable back and front cover panels for transport, making a nice ready to go colorful giging suitcase. A very clever design. As always from Dynacord, their amps were mutants and there was a nice amount of versions. The DA15 was the main product for Dynacord. 70,000 units were produced during the '50s followed by 65,000 DA16 from 1959 on. It was the most popular german amp ever and they are still easy to find. I have one of each.

The DA15/V is the more common version, the one I have. It has three channels and a so-so popping vibrato. None of the channels are guitar oriented, but they all are usable. The best one is the Mic input. This one alone worths the amp. The internal Elbau Type 22/93 speaker is not specially good, only passable at low levels and awful if pushed. But plugging it into Celestions or some Eminences it rocks. It's impressive through a Marshall 4x12" JCM800 1984A bass cab, but likes Vintage 30s and Eminence blue alnicos too. The DA16/V is a bit more refined, with a few more features added. The one I have (and late DA15s too) has a couple of plastic tweeters mounted at the sides of the suitcase. The internal speakers make a more useable set. Still shrilling, but they keep up the lows way better, perhaps the circuit was modified somewhat to solve this. I didn't tracked the DA16 circuit yet, I've only drawn the DA15 schem. There was a DA18 and a DA20. Basically a DA16 chassis with added reverb mounted on regular guitar cabs as any typical Combo, and loaded with small speakers. It loses the magic of the suitcase and don't even have a 10" speaker! A non sense! :mrgreen:

The bigger amps use to have EL12 power tubes, so not very good deals. Only the top of the line worth a mention. The impressive MV75. A monster having six channels with independent tone controls each powered by a couple of EL34. It looks like a beautiful huge old radio. I was about buying one a few times... but where would I go with that power?! I stopped using 50 watters years ago. 15 watts is the way to go gigging at clubs.

These are the main '50s amps and their evolutions. There's more to come. Stay tuned for the '60s stuff. ;)
Last edited by Snap on Mon Mar 23, 2009 8:38 pm, edited 2 times in total.
User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Re: Dynacord Amplifiers

Postby Snap » Tue Mar 17, 2009 8:35 am

...And if you feel frightened by the odd connectors on these amps panels, just check this. ;)
User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Re: Dynacord Amplifiers

Postby peer b » Wed Mar 18, 2009 1:34 pm

I had a Dynacord Jazz combo for some years. Nifty little two tone amp. Very good looking, very good sound. I really liked it a lot at home ( and I am quite spoiled by my silverface champ). The jazz had great clean tones - and a good 10 inch speaker, as far as my ears were concerned. I bought it very cheap, but did spend a fair amount of cash having it looked after by a good tech. I had NOS valves in it - wich makes all the difference, i think.

It had a 'guitar'input - with a jack- connection. It sounded reasonably clean and quite loud. But the 'mic'-input ( w/DIN connector) really rocked! The whole package was very nice - and good value for money.
Still.. I thought it was too loud for home use ( or: my neighbours thought so) and the DIN-stuff is a hassle..
I traded it.. ( yes, I regert that)

Earlier on, in the eighties, I had a Dynacord Twen. As far as I recall that was a quite fenderlike sounding combo. Really liked it, it had a 12 incher and was really loud for a small amp.. I wonder what has happened to it...?
peer b
 
Posts: 300
Joined: Sun Oct 26, 2008 10:45 am

Re: Dynacord Amplifiers

Postby Snap » Wed Mar 18, 2009 7:32 pm

I had NOS valves in it - wich makes all the difference, i think.


Absolutely! Though old amps can sound in their full glory with well chosen modern tubes. It's a hard work looking and testing for the right tubes for a particular amp

but did spend a fair amount of cash having it looked after by a good tech.


The usual problem with old worn amps. Specially electrolytic caps. They have a limited life span. It's recommended replacing them all on any electronic device after 15 years and even earlier if the device is not powered often. Electrolytic caps get dry and stop working sooner. Many vintage amps have still their original caps inside. They hardly ever are healthy so hum, noise and weak flubby lo-end or weak dull output with odd subharmonic ringings are the expected symtoms. Anyway I think it worths the expense of getting them fixed. Take a look at the guts of most modern amps. Only a few very expensive top-notch factory or boutique amps are built with these old times quality of craftmanship and components. What was a common thing in the past has became a luxury nowadays.
User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Re: Dynacord Amplifiers

Postby Snap » Wed Mar 18, 2009 7:41 pm

But the 'mic'-input ( w/DIN connector) really rocked!


Yes, the mic inputs are usually the way to go. In many old german amps they were arranged very similar to a standard guitar input. If you ever have any of these odd instrument amps, you'd probably like the mic inputs better for guitar use.
User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Re: Dynacord Amplifiers

Postby Snap » Tue Mar 24, 2009 6:46 am

Update.

I finally got some Dynacord schematics.

The DA16 and the late DA15 amps are pretty similar, and slightly different from the earlier DA15 versions. I was wondering if the first channel of my DA16 was faulty because it lacks volume compared with my earlier DA15 and very weak compared with the other DA16 channels. I discovered it's just part of the design. I don't know what kind of microphones are intended for this channel, but should be very powerful. More than any mic I know, perhaps a Dynacord special design. Well, it doesn't matter that much. In a practical (guitar) world this could be a good or bad thing. The channel 2 is the one for guitar use if you want to play a DA16 onstage with drums and other guys making noise around. But playing at home typical 15 watters can be very loud, so channel 1 shines here. You can get the amp at home friendly levels and get some tone. If anyone likes these amps and want them for live use mainly the early aluminum panel DA15 are the ones. If anyone wants using these amp onstage sparingly and playing them mainly at home, the later (and more abundant) black panel DA15 and DA16 versions are the way to go.

About the MV15 and the Miga 16 they are very different beasts after all. The first channel is a pure mic preamp, a transformer mic preamp indeed. Not very good for guitar use, but the channel two should rock anyway. The EF86 tube is not used as the first stage of a channel as I expected. :roll: :| it works as a recovery stage after the channels mixer, not bad anyway, all channels go through that tube, I think I like it. I'm a huge fan of the EF86 tube for guitar use. In fact a huge fan of pentodes (contrary to any audiophile criteria who swear there's nothing sounding better than triodes even for power stages). :mrgreen: I think these amps are very interesting, besides only one channel is guitar oriented, but hey, how many channels do you actually need? :lol:

The Miga 16 is a pure instrument amp, straightforward and without bells and whistles. Just they way I like them. I think I understand why they are hardly found for sale. I wouldn't let these amps go... even without hearing one! It has three differently voiced true guitar channels. Great! Is the single MV15 channel not enough for you? There are plenty in the Miga... it's a shame they chose to leave the EF86 tube away from this amp though. :roll:
User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Re: Dynacord Amplifiers

Postby Snap » Tue Mar 24, 2009 6:57 am

OK, let's go with the '60s combos. These later designs are truly guitar oriented made like typical guitar combos, unlike the earlier DA series or the Miga belonging to the earlier "Koffer" and "Kassetten-mischverstärker" concepts. As always, most of them are low power units. Hi power amps were not very common until mid '60s in Germany. But well conceived 15 watt devices are more than enough for gigging at cubs.

The Jazz model was the simplest amp of these combos. It has two independent channels (mic + mic/guitar) with a common tone control. It has a hardwired speaker extension output, always a welcome feature on small combos. The wide cabinet has a single 245 or 240mm (ca. 9.5") speaker mounted at one side, so it's not strange that some Jazz amps were modded with an added (10") speaker at the other side. This cabinet is quite large with a big air volume for a small speaker, so it pumps unusual big lo-end for what can be usually expected from a small speaker or a small guitar combo. It doesn't sounds boxy at all. In fact it's a very good and tonefull, clean, and detailed small amp. Just read Peer's impressions on it. There was a reverb equipped version. It is the Hall-Jazz. Essentially the same amp with an extra knob and a couple of tubes for the reverb circuit.

By late '50s and early '60s american amps were highly sought after by German players. Dynacord knew that and made two american voiced amps. They were the Amigo and Twen combos. These two amps have 6V6 output tubes instead of a more typical European power tube. I think I don't know any other European amps using american tubes by that time. Both amps shared the same cabinet and chassis and their circuits are not too far from the late Fender tweed amps. They're not copies or clones, but were inspired by them. The Amigo has a single 6V6 output tube giving 6 Watt into a couple of small speakers. It's a shame they didn't shared the Twen's 12" speaker. Anyway, It's good having two of them instead of one mounted in a rather big cabinet. These amps don't sound boxy as most tiny combos do. They are great practice amps with the old tweed grunt. The Twen is an upscaled push-pull 16 Watter. It sounds very Deluxish. Think of Neil Young's sound. It's a nice gigging amp. I had a Twen for a while and though it sounded good I sold it to a friend because it was not exactly my thing. It's just a matter of taste. The cabinet is a bit too small for what I'm expecting for a 12" enclosure plus I tend to prefer true pentodes as output tubes (EL34, EL84, 7591) more than the typical american beam tetrodes like the 6L6 and 6V6. I thought about modding the amp for using EL84 tubes instead, but I didn't liked to do it. There's plenty of good old EL84 driven amps out there. Twens are so unique to be modded this way, so I preferred to sell it and looking for something else.

Update about the Twen: I always read about Twens that they were inspired by the tweed Fender circuits, but I never found so clear such a connection. I guess everybody likes having something to say their stuff is close enough to a Fender... Well, I was comparing amps of similar topologies and I think I found the real US connection. I stumbled upon my Silvertone schematics collection and... Twens are pretty close to the GREAT Silvertone 1482! Yes, even the vibrato circuit is almost identical and equipped with the same odd US tube, a 6AU6... but the Dynacord guys reduced the grunt somewhat, perhaps they found the 1482 was breaking up too early... Well, it's another valid point of view, but the truth is that the 1482 has one of the best overdriven tones ever. Pure small rock machines. The Twens are much more polite pals in comparison, but can be easily modded into the roaring Silvertone/Danelectro specs for an overdriven sound to die for.... Hell, I've sold my Twen before discovering that!!!! :evil:

There were a couple of medium power combos too. The scarce Da Capo (I've never seen one) and the Rex. The Rex combo is a true workhorse. Derived from the King head, loaded with two EL34 delivering 35 healthy Watts into two speakers making of it a great stage tool. It has the typical German (strange) combination of slightly different sized speakers (2x~10"). I still cannot figure out the logic behind this arrangement. It's usually found in Hohner and Suprem combos too. I guess it improves articulation somehow. The Rex has two independent channels with two inputs provided with sensitivity switches and a two band equalizer each, a vibrato for the second channel, an extension speaker output and a link for an external Dynacord tape echo unit.

There was a Hallrex too, but it's not exactly a Rex with reverb. It's a much simpler amp with an EL84 power section giving 16 watt into a single speaker. It's more a Jazz-Hall variant than a Rex.
Last edited by Snap on Mon Apr 06, 2009 5:19 pm, edited 3 times in total.
User avatar
Snap
 
Posts: 8999
Joined: Tue Oct 28, 2008 9:40 am

Next

Return to West Germany

Who is online

Users browsing this forum: No registered users and 3 guests