thank you. I finally figured out how to open and print them (still learning this thing). I'm sure the one I have is '69 YBA-1A MKII, I have the schematic on the cover plate inside, it seems to be the same as your drawing. I also have worked on some of the other models. They seem to be similar. What I am curious about is this; When I first acquired this amp I took a picture of the inside component layout, everything appeared to be original, then I did some major modifications. Now I have restored everything to original but it doesn't seem to perform as well as when I first got it. Everything seems to match the diagram but in referring to my picture there are some other parts not on the schematic. Any comments, does this seem possible to you? Would the original circuit be different than the drawing inside the amp? thanks, PTI own a 1971 Bass Master YBA-1. I might want to join your list, but I need to know if this is a forum, or if I'll get lots of emails....
Mary, Boston Area .
The DynaReverb unit has surfaced at Capsule Music-416-203-0202.Toronto Ontario Canada...
Hi. I have a YSR-1 that I figure (no serial #) is about '69. I compared the two YSR-1 schematics that you have listed as '67 and '72. They are identical, as both document the same number of revisions ending with one in 8/72. Neither shows the choke or reverb drive transformer that show up on both my amp and my schematic. If you have a fax or snail mail I'll get you a copy of this earlier scheme, also dated 1/67, but it only includes 1 documented revision in '69. Dan Lear at Yorkville thinks they manufacturered the "old" YSR-1's from 4/68 through mid-70. He thought they stuck with the Jan 67 date as that's when the design was originally drawn or approved. Dan also sent me a copy of a YSR-1 sheet from a catalog and a page with YSR-1 cab combinations like YBA one you have on the site. Let me know if you need any of this stuff.
Keepin' the faith
... Dave Register
Thanks for the Traynor site! I was so psyched when I found it. Do you know anything about Traynor's old US location? It is about two miles from where I'm sitting right now in Buffalo. I'm going to see if the building is still standing, and if so, I'm going to try to get someone to let me see if I can find any old nameplates or other stuff that they might have left down in the catacombs.Oh yeah, feel free to put any info on your site that you'd like. Here are the notes that I sent/got from Yorkville. As for the manufacturing dates, I assumed that Dan was referring to the old design of the YSR-1 as we know that there are newer YSR-1s from '71-?. I think the "1st version" YSRs must be kind of rare if they were only made for 20 months, eh? But as you'll see, there are definately two different schematics for this amp.
PPS-On re-reading that dating info, I wonder if he meant YSRs were made from 4/68 to mid-1970, or the mid 70s??? So I guess the question now is, when did they redesign the chokes out of the circuit?
Dave
I e-mailed a question to Yorkville about what they exactly did over here. Could be it was just an ordering office or distribution center in order to beat customs, taxes, or international phone rates. Anyway, they got back to me last time, so maybe they will again. I will let you know.
I don't know very much about the company either, so I don't know about US variations. I can say that I never heard of any. I'll see if I can scan you a picture of the building (if it's still standing!) Where it was is now an old run down industrial section of the city. I did a lot of temporary jobs in old factories for awhile, and I'll bet I can get someone to let me in to prowl around some!
Hi guys. In getting to know my amp, I've read that the YBA-1 has attenuated and (regular) inputs, which will boost or lower the input signal, depending on which you use. Which is which?
My amp is a 1971. It's got Channel I and Channel II, with a 2 inputs each, one on top of the other. Any ideas? I've read channel I is good for bass or rhythm guitar, and channel II for guitar (more trebley).
Any words of wiz dom?Hi.. If you know anyone thats looking for and older Traynor tube amp let me know... I have a 1969 YBA-1 head with a YF-10 Four Ten cabnet... for sale, all are in very good original condition.... I believe this beast was rated at 40W to 50W output.... But it sounds rock solid...Another question on what the best configuration for my YBA-1 is. Does anyone know what the amp is built to use? Again, 1971 YBA-1. I'm using a 6x10 cabinet now, for bass, but do not know (need to find out!) the ohms for this cabinet. And if I wanted to use the ext.out, what would be the best set up? Will I get a better sound if I hooked my 15" to the ext as well as the 6x10? or lose power & quality of sound?
so many questions! :)
>Hi.. If you know anyone thats looking for and older Traynor tube amp let me know... I have a 1969 YBA-1 head with a YF-10 Four Ten cabnet... for sale, all are in very good original condition.... I believe this beast was rated at 40W to 50W output.... But it sounds rock solid...
>Another question on what the best configuration for my YBA-1 is. Does anyone know what the amp is built to use? Again, 1971 YBA-1. I'm using a 6x10 cabinet now, for bass, but do not know (need to find out!) the ohms for this cabinet. And if I wanted to use the ext.out, what would be the best set up? Will I get a better sound if I hooked my 15" to the ext as well as the 6x10? or lose power & quality of sound?
A YBA-1 has a nominal 8 ohm output, and the two speaker jacks are wired in parallel.
Assuming the 6 drivers are 8 ohms, and that they are wired so that each speaker gets the same share of the power, there are 4 different ways they can be hooked up. All 6 wired in parallel would produce a 1.33 ohm load, and all in series would be a 48 ohm load - both very unlikely. There are 2 possible series/parallel combinations, which would produce either 5.33 ohms or 12 ohms - either would be a good match with the Bassmaster. The lower impedance wiring is more likely - I have a Traynor 6 X 10" cabinet (Traynor YC-610, SN 4062296) which is labelled as 5.4 ohm cabinet.
If the 15" cabinet is also an 8 ohm speaker, then the resulting impedance when both the 6X10 (if 5.33 ohms) and the 15 are connected would be 3.2 ohms - lower than ideal for a Bassmaster, you would be losing a lot of power as a result of the impedance mismatch. Because of the impedance difference, 60 % of the power would go to the 6X10, 40% to the 15. You would probably get better sound with either speaker alone than with both together. Because of the better loading resulting from multiple drivers, the 6X10" is probably more efficient than the single 15". You would get very slightly more power into the 15" because of a better impedance match, but this would not make a noticeable difference. The solution is to try both and see which you prefer.
If the 6X10" has been wired for 12 ohms it is probably worth trying using both it and your 15" at the same time. The load would be 4.8 ohms, the 15" would receive 60% of the power and the 6X10" 40%.
It is easy to check the impedance of a cabinet with a multimeter - the DC resistance will be about 80% of the AC impedance.I am interested in purchasing a 5 year old (good condition, other then the cloth is missing from the face of the 12" speaker). What $$ should I be buying this for?
He is asking $275 Cdn
>>It seems you can run Traynors into speaker loads that are lower than the OT
>ohms...I run various YBA1 and II (both with 8 ohm OTs) into single 2-12 cabs (4 ohms), yet some sources say I'm at risk for burning up the OT and/or most of the amp, that I should rewire cabs for 16 ohm (the only other feasible set-up for a 2-12 cab). Why are Traynors immune to the dreaded lower impedence mismatch (are they?) Thanks!
This is a property of tube amps in general. It is *safer* to run tube amps into a short circuit rather than an open circuit, the reverse of the situation with transistor amps. (I'm not recommending running tube amps into very low impedances - the tubes wear out more quickly and the transformers get very hot - but they usually survive).
Most transistor amps have almost no reasonable limit in the amount of output current they can supply, given that the power supply is large enough and nothing blows up or melts down. Therefore, as their maximum output voltage is (relatively) constant, they double their power output each time the load impedance halves. If a transistor amp puts out 50 watts into 8 ohms, it would put out close to 100 watts into 4 ohms, and probably activate a shutdown circuit if run into a 2 ohm load. Without proper protection circuitry, a transistor amp will self destruct if the output is short circuited
Current in tube amps, unlike transistor amps, is limited by the number of electrons that can be emitted by the red hot cathode. As both output current and output voltage have (somewhat flexible) limits, maximum power output (where the product of current X voltage is greatest) will occur at a specific output impedance, usually close to the nominal output impedance. The turns ratio of the output transformer determines the ratio between output voltage and output current - which therefore determines what impedance load the tube amp can put out the most power into.
Tube amps usually put out about 80 % (it depends on the stiffness of the power supply) of their maximum power into a 50 percent load mismatch - a 50 watt 8 ohm output impedance amp would put out about 40 watts into either 4 or 16 ohms. This is too small a power drop to be noticeable. If the 4 ohm load is created by connecting a second identical 8 ohm speaker, the improved acoustic loading resulting from doubling the cone area would actually increase the sound output, even though power output was less. It is not a good idea to use tube amps with more than a 50% load mismatch.
Tube amps can be destroyed by being run without a load. Without speakers attached, very high voltages can be generated, resulting in insulation breakdown and arc over, destroying the output transformer and output tubes. A YBA-1 has a 180 ohm 20 watt resistor permanently wired across the speaker output to stop the amp from blowing up if the speakers are accidentally disconnected for a few seconds, but you should never run the amp without speakers connected
>Most transistor amps have almost no reasonable limit in the amount of output current they can supply, given that the power supply is large enough and nothing blows up or melts down. Therefore, as their maximum output voltage is (relatively) constant, they double their power output each time the load impedance halves. If a transistor amp puts out 50 watts into 8 ohms, it would put out close to 100 watts into 4 ohms,
My Trace Elliot puts out about 200W into 8 ohms, but only 280W into 4 ohms. Is this a limit due to the power supply?
Aaron
(... transistor output stages are typically made up of some form of a complimentary class-AB emitter follower circuit ... as load resistance/impedance is lowered the average cycle current through the load increases, as does the current flowing through the devices ... heat dissipation in the devices are inversely proportional to load rating ... hence a short (a speaker cable pulled while the amp is on - or a newly soldered cable that hasn't been checked for shorts) will fry the output within a millisecond unless short protection is designed in ...)
Probably, but it sounds like a sensible compromise. A substantial portion of the cost of an amplifier is in the power supply, output transistors, and heat sinking. If you build an amp with the capacity to put out 280 continuous watts, it is most useful to a musician dealing with varying speaker loads if it can put out most of that power into 8 ohms rather as well as 4 ohms. (It is kind of whether a glass is half empty or half full situation - it might be nice if it could put out 400 watts into 4 ohms [but it would have cost more], but on the other hand, for almost the same construction cost, it could have put out 280 watts into 4 ohms but only 140 watts into 8 ohms.) The amp has a power restricting circuit (whether just a thermal cutout switch, or something more sophisticated) to keep it from overload at low impedances. You may find that the short term maximum power output does approximately double as the impedance halves.>Hi Aaron,
>. btw, how are >things in your kneck of the woods ?!
Mostly quiet apart from beta testing an amp for a major manufacturer (don't ask me how I got the job - I don't know myself as an a amateur seems a bizzare choice). I have a trolley for my amps and the rehearsal space is a fair way from the car parking area, including some rough pavement. My trolley has solid wheels though, and I think the vibration unwound the bolt holding the transformer down. I am going to have some explaining to do tomorrow...
Aaron
Sorry about that!
It would be great to meet you, Ive been up to Vancouver many times(Great, beautiful city, really enjoyed myself there). About 10 years ago, Boeing transferred me to the deep south from Seattle. I live in Huntsville, Alabama. But hey , if you can get here...bring some Extra Old Stock with you!!
Mike Levy
>If you gig around Seattle or northern Washington sometime I'd like to come down to meet you and experience this big tone you speak of ...
>>Anything you can tell me about Traynor's US operation will be appreciated. Thanks!
>>Dave Register
Dan,
Thanks again for the answers. You should have seen the looks on those warehouse guys' faces when I went in there asking about their Traynor tenants from 25 years ago!
As you can see, I'm cc'ing this to jc, who is one of the Traynor apostles who deserves most of the credit for keeping the faith alive.
JC, I'm sending the other info, and will get you a picture of the final assembly plant that Dan refers to as soon as I get one developed.
Dave
I just saw a Traynor Bassmaster YBA-4 bass combo with one 15" speaker in it and it is powered by 2 - 6CA7 power tubes and has 3 - 12AX7 preamp tubes. I was wondering if you know anything about these amps. Are they point-to-point wired like the earlier Traynors? Are they any good for bass playing?
I'm looking for an inexpensive way to get a decent '60s type bass sound using an old Rickenbacker 4001 bass. I mainly want something that will allow the Ric to come through in the manner of Paul McCartney's '66 to '69 Ric bass sound. I will also record direct and then mix the live sound together with the direct.
Do these sound anything like a Fender Blackface Bassman amp?
Thanks for any help you may be able to provide on this amp.
Regards, Wil Mantey
I think what you're saying makes lots of sense, ... the transconductance of the output tubes (that which is seen as the conversion "rate" of input grid voltage to output plate current) stays constant under variable output load since transconductance there is set by the bias conditions of the output stage ... a larger output load means a larger reflected impedance in the output tranny primary (Vplate^ = Vin * gm * Rp^) and so also means a greater plate voltage per input volt and hence earlier clipping or saturation in output watt terms ... somebody correct me if I'm wrong ...
A lower load will cause a pentode, in a typical class AB output-stage, to be operated 'entirely' in it's ideal 'constant current' regime. This will make the output cleaner closer to breakup. Clipping will however happen sooner, counted in watts, since we now have a lower output voltage for essentially the same current. The voltage over the pentode, however, is higher and so is the dissipated wattage in the tube. i.e. the tube may croak or wear out faster. The total current consumption is higher and so powersupply sag will increase.
With a higher load-impedance much of the above reasoning is reversed. The tube is operated in a less ideal regime and so the output is less clean close to breakup. There will be less tube-wear since less power is dissipated. On the other hand The mismatch of transformer output impedance may cause voltage spikes and possibly arcing and destruction of tubes and sockets. The total current consumption is lower and so power supply sag will decrease. Output power will decrease but in this case because the current is reduced while the voltage stays about the same.
So in conclusion I guess it becomes clean and saggy versus dirty and 'solid'. Which sounds 'fatter' is beyond me ;-) And I am not an amp-guru so this posting is as much a question as a statement.
BTW, my MkIII (4ohm) came with a 16 ohm 4x12 cab. That is plenty of mismatch but it worked fine. (Quietly though) No arcing or traces thereof. Is it typical for amps to be able to handle such a different load? Or is it a special feature of, say, the huge OT of the MkIII?
/Olof Westman
I'm new to all of this, so please bear with me. I have a 1971 YBA-1 Bass Master. After talking to the owners of a Bass store, they informed me that running my amp with a 4 ohm load will sound much better than with an 8, even if the amp is set to run at 8, with a limit of 4. Will this really wear my tubes out faster? How long can I expect the tubes to last, and the cost to replace all 5, would it be better to stick to the 8. I do want to go for the best "full" tube sound I can get!!
Also: this thing about series and parallel speakers....if I were to open up my speaker cabinet, would I be able to tell how it was set up just by looking, or is there something I should know? What is the BASIC thing to know about series and parallel, and how it ultimately affects the sound of your amp/speaker combo?
If you look at the speakers, a parallel connecton means both positive terminals are connected together and both negative terminals are connected together. This type of connection gets you half the impedance of the individual speakers (i.e., two 8 ohm speakers in parallel result in a 4 ohm impedance.) Connection in series have one speaker's + connected to the other speaker's - terminal and the other + and - go to the amp. This results in the impedance of the two speakers being added.
I won't offer an opinion on the sound of the two types of connections. However the amp was designed for a specific impedance so anything less would result in a less than optimum sound from the designer's standpoint.
Lee
Mary,
Go to question #6 at this site for nice diagrams of series vs parrellel and more! http://www.webervst.com/sptalk.html
Dave
Hi JC,
Thanks for your response to my questions about the Traynor YBA-4. It was all very helpful information and I really appreciate you taking the time to get back to me so quickly!
Best Regards, Wil
Greetings, I am the owner of a couple of traynor amps. One is in need of repairs because the previous owner removed a part from the preamp board for replacement and lost it. Now I have no way of knowing for sure what the missing part is. The amp is a Traynor PM 100. (Soild state) If you can, or know of someone who can help me I would be tremendously greatful as I am stuck in the far north and all parts will have to be mail ordered. Thanks. <
I want to run my '69 Custom Reverb into a 2x10 8 ohm cabinet. I don't know what the amp's "output ohmage(?)" is, so I don't know if this is a mismatch. Can anyone help me out? Also, how do you measure the output ohmage and can you tell by looking at the schematic? What's the difference between resistance and impedence?
I've got an old style Custom Special head for sale. No bumpers. Fan is located on the side. Tolex is a little rough but not bad. Abused by the previous owner. My tech has replaced the external plug with a three prong plug and the head has been given a clean bill of health. Schematics are inside the head. Extremely powerful. $ 350.00 Canadian plus shipping. I'm in Yellowknife. Thanks very muchSubject: CUSTOM SPECIAL YBA-3
I've got an old style Custom Special head for sale. No bumpers. Fan is located on the side. Tolex is a touch rough but not bad. Abused by the previous owner. My tech has replaced the external plug with a three prong plug and the head has been given a clean bill of health. Schematics are inside the head. Extremely powerful. $ 350.00 Canadian plus shipping. I'm in Yellowknife. Thanks very much [Rick Maddeaux]
This isn't necessarily true. Guitarists often prefer to run amps into lower than rated impedance because they like the character of the distortion introduced - usually a more gradual increase than the sudden clipping that can result from running an amp into a higher than rated impedance. This is more a question of esthetics than technology. Bassists tend to want as much clean power as they can get, and therefore tend to prefer close impedance matching. The whole issue is confused by the fact that 4 ohm impedances are often the result of connecting two 8 ohm cabinets to a head. This results in more, and often better sound - as a result of better acoustic loading of the speakers ( a worse impedance match between the speakers and amp, but a better impedance match between the speakers and the air, you win more than you loose). The impedance of your 6X10 (if it is 5.3 ohms, as one would expect) is a good compromise. Trust your ears.
>Will this really wear my tubes out faster? How long can I expect the tubes to last, and the cost to replace all 5, would it be better to stick to the 8.
Yes, lower impedances will cause your output tubes to wear out sooner, but this isn't very significant. Standard Bassmasters, and other low voltage Traynors are not very hard on tubes, Mark 2s and Custom Specials are a little more demanding. You can usually expect from 1,000 to 5,000 hours use out of most output tubes. An amp that is biased hot, and used with the tubes driven into constant clipping, may only have tube life of 500 hours or less. The bias in Bassmasters is preset fairly cool, it is reasonable to hope for 2,000 hours of use - well over a year at 5 hours use a day. (Catastrophic failure due to mechanical shock shifting the tube internal structure can sometimes be a problem for gigging musicians who move their amps about a lot - but this is not affected by load impedance). Output tubes can last more than 20,000 hours - but at reduced efficiency, and with less strenuous use than a musician is likely to subject it to. I believe the legendary 300B output tube is rated by Western Electric at 40,000 hours mean time between failure (never seen a guitar amp that used them though).
Bassmasters have a pair of 6CA7/EL34 output tubes. These are cheap and easily available. Antique Electronic Supply sells very good Svetlana EL34s for about $13 each and other brands for less. The preamp and driver tubes (12AX7s) will not be affected by the speaker load, and in any case tend to last much longer than the output tubes. I have 12AX7s that have been in use for several decades and still work fine - 5,000 to 20,000 hours is not unusual.
>Also: this thing about series and parallel speakers....if I were to open up my speaker cabinet, would I be able to tell how it was set up just by looking, or is there something I should know? What is the BASIC thing to know about series and parallel, and how it ultimately affects the sound of your amp/speaker combo?
For bass guitar especially, it is worth checking the wiring to see that they are all working in phase. Your 6 X 10 cabinet is more complicated than most examples, as it requires both series and parallel wiring. It is easiest just to consider them separately. Wire each pair of speakers in series, and then treat the pair as one unit - ie. instead of six 8 ohm speakers consider them as three 16 ohm units. Then wire the three resulting 16 ohm units in parallel for a resulting 5.33 ohms (which is probably how they are now wired).
>I want to run my '69 Custom Reverb into a 2x10 8 ohm cabinet. I don't know what the amp's "output ohmage(?)" is, so I don't know if this is a mismatch.
Custom Reverbs are 8 ohms, as are most Traynors.
>Also, how do you measure the output >ohmage and can you tell by looking at the schematic?
It depends on the output transformer - you can only tell from the schematic if someone has bothered to write it in. Most Traynor schematics include the output impedance, many other schematics do not. The actual output impedance of the amp is less than one ohm, due to negative feedback (otherwise it would be several ohms). What you are really interested in is what load the amplifier will perform best with. The only way to do this is to test the amp power output into different loads - the manufacturers recommended output load (speaker impedance) will be close to the impedance where power output is greatest, (usually a little higher rather than lower than the load at which power output is greatest).
>What's the >difference between resistance and impedence?
Impedance is the reactance of the load - it includes the effect of inductance and capacitance as well as just resistance. Speakers are a complex load - a resonant circuit with a lot of inductance - just like a guitar pickup. The impedance varies with frequency - rises from the dc resistance (about 7 ohms for an 8 ohm speaker) to a much higher impedance (often over a hundred ohms) at the speaker resonance (typically between 40 and 90 hz for musical instrument speakers), falls to approximately 8 ohms above the resonant frequency and most of the midrange, and then slowly climbs to about 20 ohms at high audio frequencies due to inductance. An impedance rating for a speaker is only a nominal average.